vk_mem_alloc.h

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//
// Copyright (c) 2017-2022 Advanced Micro Devices, Inc. All rights reserved.
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#ifndef AMD_VULKAN_MEMORY_ALLOCATOR_H
#define AMD_VULKAN_MEMORY_ALLOCATOR_H

/** \mainpage Vulkan Memory Allocator

<b>Version 3.0.1 (2022-05-26)</b>

Copyright (c) 2017-2022 Advanced Micro Devices, Inc. All rights reserved. \n
License: MIT

<b>API documentation divided into groups:</b> [Modules](modules.html)

\section main_table_of_contents Table of contents

- <b>User guide</b>
  - \subpage quick_start
    - [Project setup](@ref quick_start_project_setup)
    - [Initialization](@ref quick_start_initialization)
    - [Resource allocation](@ref quick_start_resource_allocation)
  - \subpage choosing_memory_type
    - [Usage](@ref choosing_memory_type_usage)
    - [Required and preferred flags](@ref choosing_memory_type_required_preferred_flags)
    - [Explicit memory types](@ref choosing_memory_type_explicit_memory_types)
    - [Custom memory pools](@ref choosing_memory_type_custom_memory_pools)
    - [Dedicated allocations](@ref choosing_memory_type_dedicated_allocations)
  - \subpage memory_mapping
    - [Mapping functions](@ref memory_mapping_mapping_functions)
    - [Persistently mapped memory](@ref memory_mapping_persistently_mapped_memory)
    - [Cache flush and invalidate](@ref memory_mapping_cache_control)
  - \subpage staying_within_budget
    - [Querying for budget](@ref staying_within_budget_querying_for_budget)
    - [Controlling memory usage](@ref staying_within_budget_controlling_memory_usage)
  - \subpage resource_aliasing
  - \subpage custom_memory_pools
    - [Choosing memory type index](@ref custom_memory_pools_MemTypeIndex)
    - [Linear allocation algorithm](@ref linear_algorithm)
      - [Free-at-once](@ref linear_algorithm_free_at_once)
      - [Stack](@ref linear_algorithm_stack)
      - [Double stack](@ref linear_algorithm_double_stack)
      - [Ring buffer](@ref linear_algorithm_ring_buffer)
  - \subpage defragmentation
  - \subpage statistics
    - [Numeric statistics](@ref statistics_numeric_statistics)
    - [JSON dump](@ref statistics_json_dump)
  - \subpage allocation_annotation
    - [Allocation user data](@ref allocation_user_data)
    - [Allocation names](@ref allocation_names)
  - \subpage virtual_allocator
  - \subpage debugging_memory_usage
    - [Memory initialization](@ref debugging_memory_usage_initialization)
    - [Margins](@ref debugging_memory_usage_margins)
    - [Corruption detection](@ref debugging_memory_usage_corruption_detection)
  - \subpage opengl_interop
- \subpage usage_patterns
    - [GPU-only resource](@ref usage_patterns_gpu_only)
    - [Staging copy for upload](@ref usage_patterns_staging_copy_upload)
    - [Readback](@ref usage_patterns_readback)
    - [Advanced data uploading](@ref usage_patterns_advanced_data_uploading)
    - [Other use cases](@ref usage_patterns_other_use_cases)
- \subpage configuration
  - [Pointers to Vulkan functions](@ref config_Vulkan_functions)
  - [Custom host memory allocator](@ref custom_memory_allocator)
  - [Device memory allocation callbacks](@ref allocation_callbacks)
  - [Device heap memory limit](@ref heap_memory_limit)
- <b>Extension support</b>
    - \subpage vk_khr_dedicated_allocation
    - \subpage enabling_buffer_device_address
    - \subpage vk_ext_memory_priority
    - \subpage vk_amd_device_coherent_memory
- \subpage general_considerations
  - [Thread safety](@ref general_considerations_thread_safety)
  - [Versioning and compatibility](@ref general_considerations_versioning_and_compatibility)
  - [Validation layer warnings](@ref general_considerations_validation_layer_warnings)
  - [Allocation algorithm](@ref general_considerations_allocation_algorithm)
  - [Features not supported](@ref general_considerations_features_not_supported)

\section main_see_also See also

- [**Product page on GPUOpen**](https://gpuopen.com/gaming-product/vulkan-memory-allocator/)
- [**Source repository on GitHub**](https://github.com/GPUOpen-LibrariesAndSDKs/VulkanMemoryAllocator)

\defgroup group_init Library initialization

\brief API elements related to the initialization and management of the entire library, especially #VmaAllocator object.

\defgroup group_alloc Memory allocation

\brief API elements related to the allocation, deallocation, and management of Vulkan memory, buffers, images.
Most basic ones being: vmaCreateBuffer(), vmaCreateImage().

\defgroup group_virtual Virtual allocator

\brief API elements related to the mechanism of \ref virtual_allocator - using the core allocation algorithm
for user-defined purpose without allocating any real GPU memory.

\defgroup group_stats Statistics

\brief API elements that query current status of the allocator, from memory usage, budget, to full dump of the internal state in JSON format.
See documentation chapter: \ref statistics.
*/


#ifdef __cplusplus
extern "C" {
#endif

#ifndef VULKAN_H_
    #include <vulkan/vulkan.h>
#endif

// Define this macro to declare maximum supported Vulkan version in format AAABBBCCC,
// where AAA = major, BBB = minor, CCC = patch.
// If you want to use version > 1.0, it still needs to be enabled via VmaAllocatorCreateInfo::vulkanApiVersion.
#if !defined(VMA_VULKAN_VERSION)
    #if defined(VK_VERSION_1_3)
        #define VMA_VULKAN_VERSION 1003000
    #elif defined(VK_VERSION_1_2)
        #define VMA_VULKAN_VERSION 1002000
    #elif defined(VK_VERSION_1_1)
        #define VMA_VULKAN_VERSION 1001000
    #else
        #define VMA_VULKAN_VERSION 1000000
    #endif
#endif

#if defined(__ANDROID__) && defined(VK_NO_PROTOTYPES) && VMA_STATIC_VULKAN_FUNCTIONS
    extern PFN_vkGetInstanceProcAddr vkGetInstanceProcAddr;
    extern PFN_vkGetDeviceProcAddr vkGetDeviceProcAddr;
    extern PFN_vkGetPhysicalDeviceProperties vkGetPhysicalDeviceProperties;
    extern PFN_vkGetPhysicalDeviceMemoryProperties vkGetPhysicalDeviceMemoryProperties;
    extern PFN_vkAllocateMemory vkAllocateMemory;
    extern PFN_vkFreeMemory vkFreeMemory;
    extern PFN_vkMapMemory vkMapMemory;
    extern PFN_vkUnmapMemory vkUnmapMemory;
    extern PFN_vkFlushMappedMemoryRanges vkFlushMappedMemoryRanges;
    extern PFN_vkInvalidateMappedMemoryRanges vkInvalidateMappedMemoryRanges;
    extern PFN_vkBindBufferMemory vkBindBufferMemory;
    extern PFN_vkBindImageMemory vkBindImageMemory;
    extern PFN_vkGetBufferMemoryRequirements vkGetBufferMemoryRequirements;
    extern PFN_vkGetImageMemoryRequirements vkGetImageMemoryRequirements;
    extern PFN_vkCreateBuffer vkCreateBuffer;
    extern PFN_vkDestroyBuffer vkDestroyBuffer;
    extern PFN_vkCreateImage vkCreateImage;
    extern PFN_vkDestroyImage vkDestroyImage;
    extern PFN_vkCmdCopyBuffer vkCmdCopyBuffer;
    #if VMA_VULKAN_VERSION >= 1001000
        extern PFN_vkGetBufferMemoryRequirements2 vkGetBufferMemoryRequirements2;
        extern PFN_vkGetImageMemoryRequirements2 vkGetImageMemoryRequirements2;
        extern PFN_vkBindBufferMemory2 vkBindBufferMemory2;
        extern PFN_vkBindImageMemory2 vkBindImageMemory2;
        extern PFN_vkGetPhysicalDeviceMemoryProperties2 vkGetPhysicalDeviceMemoryProperties2;
    #endif // #if VMA_VULKAN_VERSION >= 1001000
#endif // #if defined(__ANDROID__) && VMA_STATIC_VULKAN_FUNCTIONS && VK_NO_PROTOTYPES

#if !defined(VMA_DEDICATED_ALLOCATION)
    #if VK_KHR_get_memory_requirements2 && VK_KHR_dedicated_allocation
        #define VMA_DEDICATED_ALLOCATION 1
    #else
        #define VMA_DEDICATED_ALLOCATION 0
    #endif
#endif

#if !defined(VMA_BIND_MEMORY2)
    #if VK_KHR_bind_memory2
        #define VMA_BIND_MEMORY2 1
    #else
        #define VMA_BIND_MEMORY2 0
    #endif
#endif

#if !defined(VMA_MEMORY_BUDGET)
    #if VK_EXT_memory_budget && (VK_KHR_get_physical_device_properties2 || VMA_VULKAN_VERSION >= 1001000)
        #define VMA_MEMORY_BUDGET 1
    #else
        #define VMA_MEMORY_BUDGET 0
    #endif
#endif

// Defined to 1 when VK_KHR_buffer_device_address device extension or equivalent core Vulkan 1.2 feature is defined in its headers.
#if !defined(VMA_BUFFER_DEVICE_ADDRESS)
    #if VK_KHR_buffer_device_address || VMA_VULKAN_VERSION >= 1002000
        #define VMA_BUFFER_DEVICE_ADDRESS 1
    #else
        #define VMA_BUFFER_DEVICE_ADDRESS 0
    #endif
#endif

// Defined to 1 when VK_EXT_memory_priority device extension is defined in Vulkan headers.
#if !defined(VMA_MEMORY_PRIORITY)
    #if VK_EXT_memory_priority
        #define VMA_MEMORY_PRIORITY 1
    #else
        #define VMA_MEMORY_PRIORITY 0
    #endif
#endif

// Defined to 1 when VK_KHR_external_memory device extension is defined in Vulkan headers.
#if !defined(VMA_EXTERNAL_MEMORY)
    #if VK_KHR_external_memory
        #define VMA_EXTERNAL_MEMORY 1
    #else
        #define VMA_EXTERNAL_MEMORY 0
    #endif
#endif

// Define these macros to decorate all public functions with additional code,
// before and after returned type, appropriately. This may be useful for
// exporting the functions when compiling VMA as a separate library. Example:
// #define VMA_CALL_PRE  __declspec(dllexport)
// #define VMA_CALL_POST __cdecl
#ifndef VMA_CALL_PRE
    #define VMA_CALL_PRE
#endif
#ifndef VMA_CALL_POST
    #define VMA_CALL_POST
#endif

// Define this macro to decorate pointers with an attribute specifying the
// length of the array they point to if they are not null.
//
// The length may be one of
// - The name of another parameter in the argument list where the pointer is declared
// - The name of another member in the struct where the pointer is declared
// - The name of a member of a struct type, meaning the value of that member in
//   the context of the call. For example
//   VMA_LEN_IF_NOT_NULL("VkPhysicalDeviceMemoryProperties::memoryHeapCount"),
//   this means the number of memory heaps available in the device associated
//   with the VmaAllocator being dealt with.
#ifndef VMA_LEN_IF_NOT_NULL
    #define VMA_LEN_IF_NOT_NULL(len)
#endif

// The VMA_NULLABLE macro is defined to be _Nullable when compiling with Clang.
// see: https://clang.llvm.org/docs/AttributeReference.html#nullable
#ifndef VMA_NULLABLE
    #ifdef __clang__
        #define VMA_NULLABLE _Nullable
    #else
        #define VMA_NULLABLE
    #endif
#endif

// The VMA_NOT_NULL macro is defined to be _Nonnull when compiling with Clang.
// see: https://clang.llvm.org/docs/AttributeReference.html#nonnull
#ifndef VMA_NOT_NULL
    #ifdef __clang__
        #define VMA_NOT_NULL _Nonnull
    #else
        #define VMA_NOT_NULL
    #endif
#endif

// If non-dispatchable handles are represented as pointers then we can give
// then nullability annotations
#ifndef VMA_NOT_NULL_NON_DISPATCHABLE
    #if defined(__LP64__) || defined(_WIN64) || (defined(__x86_64__) && !defined(__ILP32__) ) || defined(_M_X64) || defined(__ia64) || defined (_M_IA64) || defined(__aarch64__) || defined(__powerpc64__)
        #define VMA_NOT_NULL_NON_DISPATCHABLE VMA_NOT_NULL
    #else
        #define VMA_NOT_NULL_NON_DISPATCHABLE
    #endif
#endif

#ifndef VMA_NULLABLE_NON_DISPATCHABLE
    #if defined(__LP64__) || defined(_WIN64) || (defined(__x86_64__) && !defined(__ILP32__) ) || defined(_M_X64) || defined(__ia64) || defined (_M_IA64) || defined(__aarch64__) || defined(__powerpc64__)
        #define VMA_NULLABLE_NON_DISPATCHABLE VMA_NULLABLE
    #else
        #define VMA_NULLABLE_NON_DISPATCHABLE
    #endif
#endif

#ifndef VMA_STATS_STRING_ENABLED
    #define VMA_STATS_STRING_ENABLED 1
#endif

////////////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////
// 
//    INTERFACE
// 
////////////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////

// Sections for managing code placement in file, only for development purposes e.g. for convenient folding inside an IDE.
#ifndef _VMA_ENUM_DECLARATIONS

/**
\addtogroup group_init
@{
*/

/// Flags for created #VmaAllocator.
typedef enum VmaAllocatorCreateFlagBits
{
    /** \brief Allocator and all objects created from it will not be synchronized internally, so you must guarantee they are used from only one thread at a time or synchronized externally by you.

    Using this flag may increase performance because internal mutexes are not used.
    */
    VMA_ALLOCATOR_CREATE_EXTERNALLY_SYNCHRONIZED_BIT = 0x00000001,
    /** \brief Enables usage of VK_KHR_dedicated_allocation extension.

    The flag works only if VmaAllocatorCreateInfo::vulkanApiVersion `== VK_API_VERSION_1_0`.
    When it is `VK_API_VERSION_1_1`, the flag is ignored because the extension has been promoted to Vulkan 1.1.

    Using this extension will automatically allocate dedicated blocks of memory for
    some buffers and images instead of suballocating place for them out of bigger
    memory blocks (as if you explicitly used #VMA_ALLOCATION_CREATE_DEDICATED_MEMORY_BIT
    flag) when it is recommended by the driver. It may improve performance on some
    GPUs.

    You may set this flag only if you found out that following device extensions are
    supported, you enabled them while creating Vulkan device passed as
    VmaAllocatorCreateInfo::device, and you want them to be used internally by this
    library:

    - VK_KHR_get_memory_requirements2 (device extension)
    - VK_KHR_dedicated_allocation (device extension)

    When this flag is set, you can experience following warnings reported by Vulkan
    validation layer. You can ignore them.

    > vkBindBufferMemory(): Binding memory to buffer 0x2d but vkGetBufferMemoryRequirements() has not been called on that buffer.
    */
    VMA_ALLOCATOR_CREATE_KHR_DEDICATED_ALLOCATION_BIT = 0x00000002,
    /**
    Enables usage of VK_KHR_bind_memory2 extension.

    The flag works only if VmaAllocatorCreateInfo::vulkanApiVersion `== VK_API_VERSION_1_0`.
    When it is `VK_API_VERSION_1_1`, the flag is ignored because the extension has been promoted to Vulkan 1.1.

    You may set this flag only if you found out that this device extension is supported,
    you enabled it while creating Vulkan device passed as VmaAllocatorCreateInfo::device,
    and you want it to be used internally by this library.

    The extension provides functions `vkBindBufferMemory2KHR` and `vkBindImageMemory2KHR`,
    which allow to pass a chain of `pNext` structures while binding.
    This flag is required if you use `pNext` parameter in vmaBindBufferMemory2() or vmaBindImageMemory2().
    */
    VMA_ALLOCATOR_CREATE_KHR_BIND_MEMORY2_BIT = 0x00000004,
    /**
    Enables usage of VK_EXT_memory_budget extension.

    You may set this flag only if you found out that this device extension is supported,
    you enabled it while creating Vulkan device passed as VmaAllocatorCreateInfo::device,
    and you want it to be used internally by this library, along with another instance extension
    VK_KHR_get_physical_device_properties2, which is required by it (or Vulkan 1.1, where this extension is promoted).

    The extension provides query for current memory usage and budget, which will probably
    be more accurate than an estimation used by the library otherwise.
    */
    VMA_ALLOCATOR_CREATE_EXT_MEMORY_BUDGET_BIT = 0x00000008,
    /**
    Enables usage of VK_AMD_device_coherent_memory extension.

    You may set this flag only if you:

    - found out that this device extension is supported and enabled it while creating Vulkan device passed as VmaAllocatorCreateInfo::device,
    - checked that `VkPhysicalDeviceCoherentMemoryFeaturesAMD::deviceCoherentMemory` is true and set it while creating the Vulkan device,
    - want it to be used internally by this library.

    The extension and accompanying device feature provide access to memory types with
    `VK_MEMORY_PROPERTY_DEVICE_COHERENT_BIT_AMD` and `VK_MEMORY_PROPERTY_DEVICE_UNCACHED_BIT_AMD` flags.
    They are useful mostly for writing breadcrumb markers - a common method for debugging GPU crash/hang/TDR.

    When the extension is not enabled, such memory types are still enumerated, but their usage is illegal.
    To protect from this error, if you don't create the allocator with this flag, it will refuse to allocate any memory or create a custom pool in such memory type,
    returning `VK_ERROR_FEATURE_NOT_PRESENT`.
    */
    VMA_ALLOCATOR_CREATE_AMD_DEVICE_COHERENT_MEMORY_BIT = 0x00000010,
    /**
    Enables usage of "buffer device address" feature, which allows you to use function
    `vkGetBufferDeviceAddress*` to get raw GPU pointer to a buffer and pass it for usage inside a shader.

    You may set this flag only if you:

    1. (For Vulkan version < 1.2) Found as available and enabled device extension
    VK_KHR_buffer_device_address.
    This extension is promoted to core Vulkan 1.2.
    2. Found as available and enabled device feature `VkPhysicalDeviceBufferDeviceAddressFeatures::bufferDeviceAddress`.

    When this flag is set, you can create buffers with `VK_BUFFER_USAGE_SHADER_DEVICE_ADDRESS_BIT` using VMA.
    The library automatically adds `VK_MEMORY_ALLOCATE_DEVICE_ADDRESS_BIT` to
    allocated memory blocks wherever it might be needed.

    For more information, see documentation chapter \ref enabling_buffer_device_address.
    */
    VMA_ALLOCATOR_CREATE_BUFFER_DEVICE_ADDRESS_BIT = 0x00000020,
    /**
    Enables usage of VK_EXT_memory_priority extension in the library.

    You may set this flag only if you found available and enabled this device extension,
    along with `VkPhysicalDeviceMemoryPriorityFeaturesEXT::memoryPriority == VK_TRUE`,
    while creating Vulkan device passed as VmaAllocatorCreateInfo::device.

    When this flag is used, VmaAllocationCreateInfo::priority and VmaPoolCreateInfo::priority
    are used to set priorities of allocated Vulkan memory. Without it, these variables are ignored.

    A priority must be a floating-point value between 0 and 1, indicating the priority of the allocation relative to other memory allocations.
    Larger values are higher priority. The granularity of the priorities is implementation-dependent.
    It is automatically passed to every call to `vkAllocateMemory` done by the library using structure `VkMemoryPriorityAllocateInfoEXT`.
    The value to be used for default priority is 0.5.
    For more details, see the documentation of the VK_EXT_memory_priority extension.
    */
    VMA_ALLOCATOR_CREATE_EXT_MEMORY_PRIORITY_BIT = 0x00000040,

    VMA_ALLOCATOR_CREATE_FLAG_BITS_MAX_ENUM = 0x7FFFFFFF
} VmaAllocatorCreateFlagBits;
/// See #VmaAllocatorCreateFlagBits.
typedef VkFlags VmaAllocatorCreateFlags;

/** @} */

/**
\addtogroup group_alloc
@{
*/

/// \brief Intended usage of the allocated memory.
typedef enum VmaMemoryUsage
{
    /** No intended memory usage specified.
    Use other members of VmaAllocationCreateInfo to specify your requirements.
    */
    VMA_MEMORY_USAGE_UNKNOWN = 0,
    /**
    \deprecated Obsolete, preserved for backward compatibility.
    Prefers `VK_MEMORY_PROPERTY_DEVICE_LOCAL_BIT`.
    */
    VMA_MEMORY_USAGE_GPU_ONLY = 1,
    /**
    \deprecated Obsolete, preserved for backward compatibility.
    Guarantees `VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT` and `VK_MEMORY_PROPERTY_HOST_COHERENT_BIT`.
    */
    VMA_MEMORY_USAGE_CPU_ONLY = 2,
    /**
    \deprecated Obsolete, preserved for backward compatibility.
    Guarantees `VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT`, prefers `VK_MEMORY_PROPERTY_DEVICE_LOCAL_BIT`.
    */
    VMA_MEMORY_USAGE_CPU_TO_GPU = 3,
    /**
    \deprecated Obsolete, preserved for backward compatibility.
    Guarantees `VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT`, prefers `VK_MEMORY_PROPERTY_HOST_CACHED_BIT`.
    */
    VMA_MEMORY_USAGE_GPU_TO_CPU = 4,
    /**
    \deprecated Obsolete, preserved for backward compatibility.
    Prefers not `VK_MEMORY_PROPERTY_DEVICE_LOCAL_BIT`.
    */
    VMA_MEMORY_USAGE_CPU_COPY = 5,
    /**
    Lazily allocated GPU memory having `VK_MEMORY_PROPERTY_LAZILY_ALLOCATED_BIT`.
    Exists mostly on mobile platforms. Using it on desktop PC or other GPUs with no such memory type present will fail the allocation.

    Usage: Memory for transient attachment images (color attachments, depth attachments etc.), created with `VK_IMAGE_USAGE_TRANSIENT_ATTACHMENT_BIT`.

    Allocations with this usage are always created as dedicated - it implies #VMA_ALLOCATION_CREATE_DEDICATED_MEMORY_BIT.
    */
    VMA_MEMORY_USAGE_GPU_LAZILY_ALLOCATED = 6,
    /**
    Selects best memory type automatically.
    This flag is recommended for most common use cases.

    When using this flag, if you want to map the allocation (using vmaMapMemory() or #VMA_ALLOCATION_CREATE_MAPPED_BIT),
    you must pass one of the flags: #VMA_ALLOCATION_CREATE_HOST_ACCESS_SEQUENTIAL_WRITE_BIT or #VMA_ALLOCATION_CREATE_HOST_ACCESS_RANDOM_BIT
    in VmaAllocationCreateInfo::flags.
    
    It can be used only with functions that let the library know `VkBufferCreateInfo` or `VkImageCreateInfo`, e.g.
    vmaCreateBuffer(), vmaCreateImage(), vmaFindMemoryTypeIndexForBufferInfo(), vmaFindMemoryTypeIndexForImageInfo()
    and not with generic memory allocation functions.
    */
    VMA_MEMORY_USAGE_AUTO = 7,
    /**
    Selects best memory type automatically with preference for GPU (device) memory.

    When using this flag, if you want to map the allocation (using vmaMapMemory() or #VMA_ALLOCATION_CREATE_MAPPED_BIT),
    you must pass one of the flags: #VMA_ALLOCATION_CREATE_HOST_ACCESS_SEQUENTIAL_WRITE_BIT or #VMA_ALLOCATION_CREATE_HOST_ACCESS_RANDOM_BIT
    in VmaAllocationCreateInfo::flags.

    It can be used only with functions that let the library know `VkBufferCreateInfo` or `VkImageCreateInfo`, e.g.
    vmaCreateBuffer(), vmaCreateImage(), vmaFindMemoryTypeIndexForBufferInfo(), vmaFindMemoryTypeIndexForImageInfo()
    and not with generic memory allocation functions.
    */
    VMA_MEMORY_USAGE_AUTO_PREFER_DEVICE = 8,
    /**
    Selects best memory type automatically with preference for CPU (host) memory.

    When using this flag, if you want to map the allocation (using vmaMapMemory() or #VMA_ALLOCATION_CREATE_MAPPED_BIT),
    you must pass one of the flags: #VMA_ALLOCATION_CREATE_HOST_ACCESS_SEQUENTIAL_WRITE_BIT or #VMA_ALLOCATION_CREATE_HOST_ACCESS_RANDOM_BIT
    in VmaAllocationCreateInfo::flags.

    It can be used only with functions that let the library know `VkBufferCreateInfo` or `VkImageCreateInfo`, e.g.
    vmaCreateBuffer(), vmaCreateImage(), vmaFindMemoryTypeIndexForBufferInfo(), vmaFindMemoryTypeIndexForImageInfo()
    and not with generic memory allocation functions.
    */
    VMA_MEMORY_USAGE_AUTO_PREFER_HOST = 9,

    VMA_MEMORY_USAGE_MAX_ENUM = 0x7FFFFFFF
} VmaMemoryUsage;

/// Flags to be passed as VmaAllocationCreateInfo::flags.
typedef enum VmaAllocationCreateFlagBits
{
    /** \brief Set this flag if the allocation should have its own memory block.

    Use it for special, big resources, like fullscreen images used as attachments.
    */
    VMA_ALLOCATION_CREATE_DEDICATED_MEMORY_BIT = 0x00000001,

    /** \brief Set this flag to only try to allocate from existing `VkDeviceMemory` blocks and never create new such block.

    If new allocation cannot be placed in any of the existing blocks, allocation
    fails with `VK_ERROR_OUT_OF_DEVICE_MEMORY` error.

    You should not use #VMA_ALLOCATION_CREATE_DEDICATED_MEMORY_BIT and
    #VMA_ALLOCATION_CREATE_NEVER_ALLOCATE_BIT at the same time. It makes no sense.
    */
    VMA_ALLOCATION_CREATE_NEVER_ALLOCATE_BIT = 0x00000002,
    /** \brief Set this flag to use a memory that will be persistently mapped and retrieve pointer to it.

    Pointer to mapped memory will be returned through VmaAllocationInfo::pMappedData.

    It is valid to use this flag for allocation made from memory type that is not
    `HOST_VISIBLE`. This flag is then ignored and memory is not mapped. This is
    useful if you need an allocation that is efficient to use on GPU
    (`DEVICE_LOCAL`) and still want to map it directly if possible on platforms that
    support it (e.g. Intel GPU).
    */
    VMA_ALLOCATION_CREATE_MAPPED_BIT = 0x00000004,
    /** \deprecated Preserved for backward compatibility. Consider using vmaSetAllocationName() instead.
    
    Set this flag to treat VmaAllocationCreateInfo::pUserData as pointer to a
    null-terminated string. Instead of copying pointer value, a local copy of the
    string is made and stored in allocation's `pName`. The string is automatically
    freed together with the allocation. It is also used in vmaBuildStatsString().
    */
    VMA_ALLOCATION_CREATE_USER_DATA_COPY_STRING_BIT = 0x00000020,
    /** Allocation will be created from upper stack in a double stack pool.

    This flag is only allowed for custom pools created with #VMA_POOL_CREATE_LINEAR_ALGORITHM_BIT flag.
    */
    VMA_ALLOCATION_CREATE_UPPER_ADDRESS_BIT = 0x00000040,
    /** Create both buffer/image and allocation, but don't bind them together.
    It is useful when you want to bind yourself to do some more advanced binding, e.g. using some extensions.
    The flag is meaningful only with functions that bind by default: vmaCreateBuffer(), vmaCreateImage().
    Otherwise it is ignored.

    If you want to make sure the new buffer/image is not tied to the new memory allocation
    through `VkMemoryDedicatedAllocateInfoKHR` structure in case the allocation ends up in its own memory block,
    use also flag #VMA_ALLOCATION_CREATE_CAN_ALIAS_BIT.
    */
    VMA_ALLOCATION_CREATE_DONT_BIND_BIT = 0x00000080,
    /** Create allocation only if additional device memory required for it, if any, won't exceed
    memory budget. Otherwise return `VK_ERROR_OUT_OF_DEVICE_MEMORY`.
    */
    VMA_ALLOCATION_CREATE_WITHIN_BUDGET_BIT = 0x00000100,
    /** \brief Set this flag if the allocated memory will have aliasing resources.
    
    Usage of this flag prevents supplying `VkMemoryDedicatedAllocateInfoKHR` when #VMA_ALLOCATION_CREATE_DEDICATED_MEMORY_BIT is specified.
    Otherwise created dedicated memory will not be suitable for aliasing resources, resulting in Vulkan Validation Layer errors.
    */
    VMA_ALLOCATION_CREATE_CAN_ALIAS_BIT = 0x00000200,
    /**
    Requests possibility to map the allocation (using vmaMapMemory() or #VMA_ALLOCATION_CREATE_MAPPED_BIT).
    
    - If you use #VMA_MEMORY_USAGE_AUTO or other `VMA_MEMORY_USAGE_AUTO*` value,
      you must use this flag to be able to map the allocation. Otherwise, mapping is incorrect.
    - If you use other value of #VmaMemoryUsage, this flag is ignored and mapping is always possible in memory types that are `HOST_VISIBLE`.
      This includes allocations created in \ref custom_memory_pools.

    Declares that mapped memory will only be written sequentially, e.g. using `memcpy()` or a loop writing number-by-number,
    never read or accessed randomly, so a memory type can be selected that is uncached and write-combined.

    \warning Violating this declaration may work correctly, but will likely be very slow.
    Watch out for implicit reads introduced by doing e.g. `pMappedData[i] += x;`
    Better prepare your data in a local variable and `memcpy()` it to the mapped pointer all at once.
    */
    VMA_ALLOCATION_CREATE_HOST_ACCESS_SEQUENTIAL_WRITE_BIT = 0x00000400,
    /**
    Requests possibility to map the allocation (using vmaMapMemory() or #VMA_ALLOCATION_CREATE_MAPPED_BIT).
    
    - If you use #VMA_MEMORY_USAGE_AUTO or other `VMA_MEMORY_USAGE_AUTO*` value,
      you must use this flag to be able to map the allocation. Otherwise, mapping is incorrect.
    - If you use other value of #VmaMemoryUsage, this flag is ignored and mapping is always possible in memory types that are `HOST_VISIBLE`.
      This includes allocations created in \ref custom_memory_pools.

    Declares that mapped memory can be read, written, and accessed in random order,
    so a `HOST_CACHED` memory type is required.
    */
    VMA_ALLOCATION_CREATE_HOST_ACCESS_RANDOM_BIT = 0x00000800,
    /**
    Together with #VMA_ALLOCATION_CREATE_HOST_ACCESS_SEQUENTIAL_WRITE_BIT or #VMA_ALLOCATION_CREATE_HOST_ACCESS_RANDOM_BIT,
    it says that despite request for host access, a not-`HOST_VISIBLE` memory type can be selected
    if it may improve performance.

    By using this flag, you declare that you will check if the allocation ended up in a `HOST_VISIBLE` memory type
    (e.g. using vmaGetAllocationMemoryProperties()) and if not, you will create some "staging" buffer and
    issue an explicit transfer to write/read your data.
    To prepare for this possibility, don't forget to add appropriate flags like
    `VK_BUFFER_USAGE_TRANSFER_DST_BIT`, `VK_BUFFER_USAGE_TRANSFER_SRC_BIT` to the parameters of created buffer or image.
    */
    VMA_ALLOCATION_CREATE_HOST_ACCESS_ALLOW_TRANSFER_INSTEAD_BIT = 0x00001000,
    /** Allocation strategy that chooses smallest possible free range for the allocation
    to minimize memory usage and fragmentation, possibly at the expense of allocation time.
    */
    VMA_ALLOCATION_CREATE_STRATEGY_MIN_MEMORY_BIT = 0x00010000,
    /** Allocation strategy that chooses first suitable free range for the allocation -
    not necessarily in terms of the smallest offset but the one that is easiest and fastest to find
    to minimize allocation time, possibly at the expense of allocation quality.
    */
    VMA_ALLOCATION_CREATE_STRATEGY_MIN_TIME_BIT = 0x00020000,
    /** Allocation strategy that chooses always the lowest offset in available space.
    This is not the most efficient strategy but achieves highly packed data.
    Used internally by defragmentation, not recomended in typical usage.
    */
    VMA_ALLOCATION_CREATE_STRATEGY_MIN_OFFSET_BIT  = 0x00040000,
    /** Alias to #VMA_ALLOCATION_CREATE_STRATEGY_MIN_MEMORY_BIT.
    */
    VMA_ALLOCATION_CREATE_STRATEGY_BEST_FIT_BIT = VMA_ALLOCATION_CREATE_STRATEGY_MIN_MEMORY_BIT,
    /** Alias to #VMA_ALLOCATION_CREATE_STRATEGY_MIN_TIME_BIT.
    */
    VMA_ALLOCATION_CREATE_STRATEGY_FIRST_FIT_BIT = VMA_ALLOCATION_CREATE_STRATEGY_MIN_TIME_BIT,
    /** A bit mask to extract only `STRATEGY` bits from entire set of flags.
    */
    VMA_ALLOCATION_CREATE_STRATEGY_MASK =
        VMA_ALLOCATION_CREATE_STRATEGY_MIN_MEMORY_BIT |
        VMA_ALLOCATION_CREATE_STRATEGY_MIN_TIME_BIT |
        VMA_ALLOCATION_CREATE_STRATEGY_MIN_OFFSET_BIT,

    VMA_ALLOCATION_CREATE_FLAG_BITS_MAX_ENUM = 0x7FFFFFFF
} VmaAllocationCreateFlagBits;
/// See #VmaAllocationCreateFlagBits.
typedef VkFlags VmaAllocationCreateFlags;

/// Flags to be passed as VmaPoolCreateInfo::flags.
typedef enum VmaPoolCreateFlagBits
{
    /** \brief Use this flag if you always allocate only buffers and linear images or only optimal images out of this pool and so Buffer-Image Granularity can be ignored.

    This is an optional optimization flag.

    If you always allocate using vmaCreateBuffer(), vmaCreateImage(),
    vmaAllocateMemoryForBuffer(), then you don't need to use it because allocator
    knows exact type of your allocations so it can handle Buffer-Image Granularity
    in the optimal way.

    If you also allocate using vmaAllocateMemoryForImage() or vmaAllocateMemory(),
    exact type of such allocations is not known, so allocator must be conservative
    in handling Buffer-Image Granularity, which can lead to suboptimal allocation
    (wasted memory). In that case, if you can make sure you always allocate only
    buffers and linear images or only optimal images out of this pool, use this flag
    to make allocator disregard Buffer-Image Granularity and so make allocations
    faster and more optimal.
    */
    VMA_POOL_CREATE_IGNORE_BUFFER_IMAGE_GRANULARITY_BIT = 0x00000002,

    /** \brief Enables alternative, linear allocation algorithm in this pool.

    Specify this flag to enable linear allocation algorithm, which always creates
    new allocations after last one and doesn't reuse space from allocations freed in
    between. It trades memory consumption for simplified algorithm and data
    structure, which has better performance and uses less memory for metadata.

    By using this flag, you can achieve behavior of free-at-once, stack,
    ring buffer, and double stack.
    For details, see documentation chapter \ref linear_algorithm.
    */
    VMA_POOL_CREATE_LINEAR_ALGORITHM_BIT = 0x00000004,

    /** Bit mask to extract only `ALGORITHM` bits from entire set of flags.
    */
    VMA_POOL_CREATE_ALGORITHM_MASK =
        VMA_POOL_CREATE_LINEAR_ALGORITHM_BIT,

    VMA_POOL_CREATE_FLAG_BITS_MAX_ENUM = 0x7FFFFFFF
} VmaPoolCreateFlagBits;
/// Flags to be passed as VmaPoolCreateInfo::flags. See #VmaPoolCreateFlagBits.
typedef VkFlags VmaPoolCreateFlags;

/// Flags to be passed as VmaDefragmentationInfo::flags.
typedef enum VmaDefragmentationFlagBits
{
    /* \brief Use simple but fast algorithm for defragmentation.
    May not achieve best results but will require least time to compute and least allocations to copy.
    */
    VMA_DEFRAGMENTATION_FLAG_ALGORITHM_FAST_BIT = 0x1,
    /* \brief Default defragmentation algorithm, applied also when no `ALGORITHM` flag is specified.
    Offers a balance between defragmentation quality and the amount of allocations and bytes that need to be moved.
    */
    VMA_DEFRAGMENTATION_FLAG_ALGORITHM_BALANCED_BIT = 0x2,
    /* \brief Perform full defragmentation of memory.
    Can result in notably more time to compute and allocations to copy, but will achieve best memory packing.
    */
    VMA_DEFRAGMENTATION_FLAG_ALGORITHM_FULL_BIT = 0x4,
    /** \brief Use the most roboust algorithm at the cost of time to compute and number of copies to make.
    Only available when bufferImageGranularity is greater than 1, since it aims to reduce
    alignment issues between different types of resources.
    Otherwise falls back to same behavior as #VMA_DEFRAGMENTATION_FLAG_ALGORITHM_FULL_BIT.
    */
    VMA_DEFRAGMENTATION_FLAG_ALGORITHM_EXTENSIVE_BIT = 0x8,

    /// A bit mask to extract only `ALGORITHM` bits from entire set of flags.
    VMA_DEFRAGMENTATION_FLAG_ALGORITHM_MASK = 
        VMA_DEFRAGMENTATION_FLAG_ALGORITHM_FAST_BIT |
        VMA_DEFRAGMENTATION_FLAG_ALGORITHM_BALANCED_BIT |
        VMA_DEFRAGMENTATION_FLAG_ALGORITHM_FULL_BIT |
        VMA_DEFRAGMENTATION_FLAG_ALGORITHM_EXTENSIVE_BIT,

    VMA_DEFRAGMENTATION_FLAG_BITS_MAX_ENUM = 0x7FFFFFFF
} VmaDefragmentationFlagBits;
/// See #VmaDefragmentationFlagBits.
typedef VkFlags VmaDefragmentationFlags;

/// Operation performed on single defragmentation move. See structure #VmaDefragmentationMove.
typedef enum VmaDefragmentationMoveOperation
{
    /// Buffer/image has been recreated at `dstTmpAllocation`, data has been copied, old buffer/image has been destroyed. `srcAllocation` should be changed to point to the new place. This is the default value set by vmaBeginDefragmentationPass().
    VMA_DEFRAGMENTATION_MOVE_OPERATION_COPY = 0,
    /// Set this value if you cannot move the allocation. New place reserved at `dstTmpAllocation` will be freed. `srcAllocation` will remain unchanged.
    VMA_DEFRAGMENTATION_MOVE_OPERATION_IGNORE = 1,
    /// Set this value if you decide to abandon the allocation and you destroyed the buffer/image. New place reserved at `dstTmpAllocation` will be freed, along with `srcAllocation`, which will be destroyed.
    VMA_DEFRAGMENTATION_MOVE_OPERATION_DESTROY = 2,
} VmaDefragmentationMoveOperation;

/** @} */

/**
\addtogroup group_virtual
@{
*/

/// Flags to be passed as VmaVirtualBlockCreateInfo::flags.
typedef enum VmaVirtualBlockCreateFlagBits
{
    /** \brief Enables alternative, linear allocation algorithm in this virtual block.

    Specify this flag to enable linear allocation algorithm, which always creates
    new allocations after last one and doesn't reuse space from allocations freed in
    between. It trades memory consumption for simplified algorithm and data
    structure, which has better performance and uses less memory for metadata.

    By using this flag, you can achieve behavior of free-at-once, stack,
    ring buffer, and double stack.
    For details, see documentation chapter \ref linear_algorithm.
    */
    VMA_VIRTUAL_BLOCK_CREATE_LINEAR_ALGORITHM_BIT = 0x00000001,

    /** \brief Bit mask to extract only `ALGORITHM` bits from entire set of flags.
    */
    VMA_VIRTUAL_BLOCK_CREATE_ALGORITHM_MASK =
        VMA_VIRTUAL_BLOCK_CREATE_LINEAR_ALGORITHM_BIT,

    VMA_VIRTUAL_BLOCK_CREATE_FLAG_BITS_MAX_ENUM = 0x7FFFFFFF
} VmaVirtualBlockCreateFlagBits;
/// Flags to be passed as VmaVirtualBlockCreateInfo::flags. See #VmaVirtualBlockCreateFlagBits.
typedef VkFlags VmaVirtualBlockCreateFlags;

/// Flags to be passed as VmaVirtualAllocationCreateInfo::flags.
typedef enum VmaVirtualAllocationCreateFlagBits
{
    /** \brief Allocation will be created from upper stack in a double stack pool.

    This flag is only allowed for virtual blocks created with #VMA_VIRTUAL_BLOCK_CREATE_LINEAR_ALGORITHM_BIT flag.
    */
    VMA_VIRTUAL_ALLOCATION_CREATE_UPPER_ADDRESS_BIT = VMA_ALLOCATION_CREATE_UPPER_ADDRESS_BIT,
    /** \brief Allocation strategy that tries to minimize memory usage.
    */
    VMA_VIRTUAL_ALLOCATION_CREATE_STRATEGY_MIN_MEMORY_BIT = VMA_ALLOCATION_CREATE_STRATEGY_MIN_MEMORY_BIT,
    /** \brief Allocation strategy that tries to minimize allocation time.
    */
    VMA_VIRTUAL_ALLOCATION_CREATE_STRATEGY_MIN_TIME_BIT = VMA_ALLOCATION_CREATE_STRATEGY_MIN_TIME_BIT,
    /** Allocation strategy that chooses always the lowest offset in available space.
    This is not the most efficient strategy but achieves highly packed data.
    */
    VMA_VIRTUAL_ALLOCATION_CREATE_STRATEGY_MIN_OFFSET_BIT = VMA_ALLOCATION_CREATE_STRATEGY_MIN_OFFSET_BIT,
    /** \brief A bit mask to extract only `STRATEGY` bits from entire set of flags.

    These strategy flags are binary compatible with equivalent flags in #VmaAllocationCreateFlagBits.
    */
    VMA_VIRTUAL_ALLOCATION_CREATE_STRATEGY_MASK = VMA_ALLOCATION_CREATE_STRATEGY_MASK,

    VMA_VIRTUAL_ALLOCATION_CREATE_FLAG_BITS_MAX_ENUM = 0x7FFFFFFF
} VmaVirtualAllocationCreateFlagBits;
/// Flags to be passed as VmaVirtualAllocationCreateInfo::flags. See #VmaVirtualAllocationCreateFlagBits.
typedef VkFlags VmaVirtualAllocationCreateFlags;

/** @} */

#endif // _VMA_ENUM_DECLARATIONS

#ifndef _VMA_DATA_TYPES_DECLARATIONS

/**
\addtogroup group_init
@{ */

/** \struct VmaAllocator
\brief Represents main object of this library initialized.

Fill structure #VmaAllocatorCreateInfo and call function vmaCreateAllocator() to create it.
Call function vmaDestroyAllocator() to destroy it.

It is recommended to create just one object of this type per `VkDevice` object,
right after Vulkan is initialized and keep it alive until before Vulkan device is destroyed.
*/
VK_DEFINE_HANDLE(VmaAllocator)

/** @} */

/**
\addtogroup group_alloc
@{
*/

/** \struct VmaPool
\brief Represents custom memory pool

Fill structure VmaPoolCreateInfo and call function vmaCreatePool() to create it.
Call function vmaDestroyPool() to destroy it.

For more information see [Custom memory pools](@ref choosing_memory_type_custom_memory_pools).
*/
VK_DEFINE_HANDLE(VmaPool)

/** \struct VmaAllocation
\brief Represents single memory allocation.

It may be either dedicated block of `VkDeviceMemory` or a specific region of a bigger block of this type
plus unique offset.

There are multiple ways to create such object.
You need to fill structure VmaAllocationCreateInfo.
For more information see [Choosing memory type](@ref choosing_memory_type).

Although the library provides convenience functions that create Vulkan buffer or image,
allocate memory for it and bind them together,
binding of the allocation to a buffer or an image is out of scope of the allocation itself.
Allocation object can exist without buffer/image bound,
binding can be done manually by the user, and destruction of it can be done
independently of destruction of the allocation.

The object also remembers its size and some other information.
To retrieve this information, use function vmaGetAllocationInfo() and inspect
returned structure VmaAllocationInfo.
*/
VK_DEFINE_HANDLE(VmaAllocation)

/** \struct VmaDefragmentationContext
\brief An opaque object that represents started defragmentation process.

Fill structure #VmaDefragmentationInfo and call function vmaBeginDefragmentation() to create it.
Call function vmaEndDefragmentation() to destroy it.
*/
VK_DEFINE_HANDLE(VmaDefragmentationContext)

/** @} */

/**
\addtogroup group_virtual
@{
*/

/** \struct VmaVirtualAllocation
\brief Represents single memory allocation done inside VmaVirtualBlock.

Use it as a unique identifier to virtual allocation within the single block.

Use value `VK_NULL_HANDLE` to represent a null/invalid allocation.
*/
VK_DEFINE_NON_DISPATCHABLE_HANDLE(VmaVirtualAllocation);

/** @} */

/**
\addtogroup group_virtual
@{
*/

/** \struct VmaVirtualBlock
\brief Handle to a virtual block object that allows to use core allocation algorithm without allocating any real GPU memory.

Fill in #VmaVirtualBlockCreateInfo structure and use vmaCreateVirtualBlock() to create it. Use vmaDestroyVirtualBlock() to destroy it.
For more information, see documentation chapter \ref virtual_allocator.

This object is not thread-safe - should not be used from multiple threads simultaneously, must be synchronized externally.
*/
VK_DEFINE_HANDLE(VmaVirtualBlock)

/** @} */

/**
\addtogroup group_init
@{
*/

/// Callback function called after successful vkAllocateMemory.
typedef void (VKAPI_PTR* PFN_vmaAllocateDeviceMemoryFunction)(
    VmaAllocator VMA_NOT_NULL                    allocator,
    uint32_t                                     memoryType,
    VkDeviceMemory VMA_NOT_NULL_NON_DISPATCHABLE memory,
    VkDeviceSize                                 size,
    void* VMA_NULLABLE                           pUserData);

/// Callback function called before vkFreeMemory.
typedef void (VKAPI_PTR* PFN_vmaFreeDeviceMemoryFunction)(
    VmaAllocator VMA_NOT_NULL                    allocator,
    uint32_t                                     memoryType,
    VkDeviceMemory VMA_NOT_NULL_NON_DISPATCHABLE memory,
    VkDeviceSize                                 size,
    void* VMA_NULLABLE                           pUserData);

/** \brief Set of callbacks that the library will call for `vkAllocateMemory` and `vkFreeMemory`.

Provided for informative purpose, e.g. to gather statistics about number of
allocations or total amount of memory allocated in Vulkan.

Used in VmaAllocatorCreateInfo::pDeviceMemoryCallbacks.
*/
typedef struct VmaDeviceMemoryCallbacks
{
    /// Optional, can be null.
    PFN_vmaAllocateDeviceMemoryFunction VMA_NULLABLE pfnAllocate;
    /// Optional, can be null.
    PFN_vmaFreeDeviceMemoryFunction VMA_NULLABLE pfnFree;
    /// Optional, can be null.
    void* VMA_NULLABLE pUserData;
} VmaDeviceMemoryCallbacks;

/** \brief Pointers to some Vulkan functions - a subset used by the library.

Used in VmaAllocatorCreateInfo::pVulkanFunctions.
*/
typedef struct VmaVulkanFunctions
{
    /// Required when using VMA_DYNAMIC_VULKAN_FUNCTIONS.
    PFN_vkGetInstanceProcAddr VMA_NULLABLE vkGetInstanceProcAddr;
    /// Required when using VMA_DYNAMIC_VULKAN_FUNCTIONS.
    PFN_vkGetDeviceProcAddr VMA_NULLABLE vkGetDeviceProcAddr;
    PFN_vkGetPhysicalDeviceProperties VMA_NULLABLE vkGetPhysicalDeviceProperties;
    PFN_vkGetPhysicalDeviceMemoryProperties VMA_NULLABLE vkGetPhysicalDeviceMemoryProperties;
    PFN_vkAllocateMemory VMA_NULLABLE vkAllocateMemory;
    PFN_vkFreeMemory VMA_NULLABLE vkFreeMemory;
    PFN_vkMapMemory VMA_NULLABLE vkMapMemory;
    PFN_vkUnmapMemory VMA_NULLABLE vkUnmapMemory;
    PFN_vkFlushMappedMemoryRanges VMA_NULLABLE vkFlushMappedMemoryRanges;
    PFN_vkInvalidateMappedMemoryRanges VMA_NULLABLE vkInvalidateMappedMemoryRanges;
    PFN_vkBindBufferMemory VMA_NULLABLE vkBindBufferMemory;
    PFN_vkBindImageMemory VMA_NULLABLE vkBindImageMemory;
    PFN_vkGetBufferMemoryRequirements VMA_NULLABLE vkGetBufferMemoryRequirements;
    PFN_vkGetImageMemoryRequirements VMA_NULLABLE vkGetImageMemoryRequirements;
    PFN_vkCreateBuffer VMA_NULLABLE vkCreateBuffer;
    PFN_vkDestroyBuffer VMA_NULLABLE vkDestroyBuffer;
    PFN_vkCreateImage VMA_NULLABLE vkCreateImage;
    PFN_vkDestroyImage VMA_NULLABLE vkDestroyImage;
    PFN_vkCmdCopyBuffer VMA_NULLABLE vkCmdCopyBuffer;
#if VMA_DEDICATED_ALLOCATION || VMA_VULKAN_VERSION >= 1001000
    /// Fetch "vkGetBufferMemoryRequirements2" on Vulkan >= 1.1, fetch "vkGetBufferMemoryRequirements2KHR" when using VK_KHR_dedicated_allocation extension.
    PFN_vkGetBufferMemoryRequirements2KHR VMA_NULLABLE vkGetBufferMemoryRequirements2KHR;
    /// Fetch "vkGetImageMemoryRequirements2" on Vulkan >= 1.1, fetch "vkGetImageMemoryRequirements2KHR" when using VK_KHR_dedicated_allocation extension.
    PFN_vkGetImageMemoryRequirements2KHR VMA_NULLABLE vkGetImageMemoryRequirements2KHR;
#endif
#if VMA_BIND_MEMORY2 || VMA_VULKAN_VERSION >= 1001000
    /// Fetch "vkBindBufferMemory2" on Vulkan >= 1.1, fetch "vkBindBufferMemory2KHR" when using VK_KHR_bind_memory2 extension.
    PFN_vkBindBufferMemory2KHR VMA_NULLABLE vkBindBufferMemory2KHR;
    /// Fetch "vkBindImageMemory2" on Vulkan >= 1.1, fetch "vkBindImageMemory2KHR" when using VK_KHR_bind_memory2 extension.
    PFN_vkBindImageMemory2KHR VMA_NULLABLE vkBindImageMemory2KHR;
#endif
#if VMA_MEMORY_BUDGET || VMA_VULKAN_VERSION >= 1001000
    PFN_vkGetPhysicalDeviceMemoryProperties2KHR VMA_NULLABLE vkGetPhysicalDeviceMemoryProperties2KHR;
#endif
#if VMA_VULKAN_VERSION >= 1003000
    /// Fetch from "vkGetDeviceBufferMemoryRequirements" on Vulkan >= 1.3, but you can also fetch it from "vkGetDeviceBufferMemoryRequirementsKHR" if you enabled extension VK_KHR_maintenance4.
    PFN_vkGetDeviceBufferMemoryRequirements VMA_NULLABLE vkGetDeviceBufferMemoryRequirements;
    /// Fetch from "vkGetDeviceImageMemoryRequirements" on Vulkan >= 1.3, but you can also fetch it from "vkGetDeviceImageMemoryRequirementsKHR" if you enabled extension VK_KHR_maintenance4.
    PFN_vkGetDeviceImageMemoryRequirements VMA_NULLABLE vkGetDeviceImageMemoryRequirements;
#endif
} VmaVulkanFunctions;

/// Description of a Allocator to be created.
typedef struct VmaAllocatorCreateInfo
{
    /// Flags for created allocator. Use #VmaAllocatorCreateFlagBits enum.
    VmaAllocatorCreateFlags flags;
    /// Vulkan physical device.
    /** It must be valid throughout whole lifetime of created allocator. */
    VkPhysicalDevice VMA_NOT_NULL physicalDevice;
    /// Vulkan device.
    /** It must be valid throughout whole lifetime of created allocator. */
    VkDevice VMA_NOT_NULL device;
    /// Preferred size of a single `VkDeviceMemory` block to be allocated from large heaps > 1 GiB. Optional.
    /** Set to 0 to use default, which is currently 256 MiB. */
    VkDeviceSize preferredLargeHeapBlockSize;
    /// Custom CPU memory allocation callbacks. Optional.
    /** Optional, can be null. When specified, will also be used for all CPU-side memory allocations. */
    const VkAllocationCallbacks* VMA_NULLABLE pAllocationCallbacks;
    /// Informative callbacks for `vkAllocateMemory`, `vkFreeMemory`. Optional.
    /** Optional, can be null. */
    const VmaDeviceMemoryCallbacks* VMA_NULLABLE pDeviceMemoryCallbacks;
    /** \brief Either null or a pointer to an array of limits on maximum number of bytes that can be allocated out of particular Vulkan memory heap.

    If not NULL, it must be a pointer to an array of
    `VkPhysicalDeviceMemoryProperties::memoryHeapCount` elements, defining limit on
    maximum number of bytes that can be allocated out of particular Vulkan memory
    heap.

    Any of the elements may be equal to `VK_WHOLE_SIZE`, which means no limit on that
    heap. This is also the default in case of `pHeapSizeLimit` = NULL.

    If there is a limit defined for a heap:

    - If user tries to allocate more memory from that heap using this allocator,
      the allocation fails with `VK_ERROR_OUT_OF_DEVICE_MEMORY`.
    - If the limit is smaller than heap size reported in `VkMemoryHeap::size`, the
      value of this limit will be reported instead when using vmaGetMemoryProperties().

    Warning! Using this feature may not be equivalent to installing a GPU with
    smaller amount of memory, because graphics driver doesn't necessary fail new
    allocations with `VK_ERROR_OUT_OF_DEVICE_MEMORY` result when memory capacity is
    exceeded. It may return success and just silently migrate some device memory
    blocks to system RAM. This driver behavior can also be controlled using
    VK_AMD_memory_overallocation_behavior extension.
    */
    const VkDeviceSize* VMA_NULLABLE VMA_LEN_IF_NOT_NULL("VkPhysicalDeviceMemoryProperties::memoryHeapCount") pHeapSizeLimit;

    /** \brief Pointers to Vulkan functions. Can be null.

    For details see [Pointers to Vulkan functions](@ref config_Vulkan_functions).
    */
    const VmaVulkanFunctions* VMA_NULLABLE pVulkanFunctions;
    /** \brief Handle to Vulkan instance object.

    Starting from version 3.0.0 this member is no longer optional, it must be set!
    */
    VkInstance VMA_NOT_NULL instance;
    /** \brief Optional. The highest version of Vulkan that the application is designed to use.

    It must be a value in the format as created by macro `VK_MAKE_VERSION` or a constant like: `VK_API_VERSION_1_1`, `VK_API_VERSION_1_0`.
    The patch version number specified is ignored. Only the major and minor versions are considered.
    It must be less or equal (preferably equal) to value as passed to `vkCreateInstance` as `VkApplicationInfo::apiVersion`.
    Only versions 1.0, 1.1, 1.2, 1.3 are supported by the current implementation.
    Leaving it initialized to zero is equivalent to `VK_API_VERSION_1_0`.
    */
    uint32_t vulkanApiVersion;
#if VMA_EXTERNAL_MEMORY
    /** \brief Either null or a pointer to an array of external memory handle types for each Vulkan memory type.

    If not NULL, it must be a pointer to an array of `VkPhysicalDeviceMemoryProperties::memoryTypeCount`
    elements, defining external memory handle types of particular Vulkan memory type,
    to be passed using `VkExportMemoryAllocateInfoKHR`.

    Any of the elements may be equal to 0, which means not to use `VkExportMemoryAllocateInfoKHR` on this memory type.
    This is also the default in case of `pTypeExternalMemoryHandleTypes` = NULL.
    */
    const VkExternalMemoryHandleTypeFlagsKHR* VMA_NULLABLE VMA_LEN_IF_NOT_NULL("VkPhysicalDeviceMemoryProperties::memoryTypeCount") pTypeExternalMemoryHandleTypes;
#endif // #if VMA_EXTERNAL_MEMORY
} VmaAllocatorCreateInfo;

/// Information about existing #VmaAllocator object.
typedef struct VmaAllocatorInfo
{
    /** \brief Handle to Vulkan instance object.

    This is the same value as has been passed through VmaAllocatorCreateInfo::instance.
    */
    VkInstance VMA_NOT_NULL instance;
    /** \brief Handle to Vulkan physical device object.

    This is the same value as has been passed through VmaAllocatorCreateInfo::physicalDevice.
    */
    VkPhysicalDevice VMA_NOT_NULL physicalDevice;
    /** \brief Handle to Vulkan device object.

    This is the same value as has been passed through VmaAllocatorCreateInfo::device.
    */
    VkDevice VMA_NOT_NULL device;
} VmaAllocatorInfo;

/** @} */

/**
\addtogroup group_stats
@{
*/

/** \brief Calculated statistics of memory usage e.g. in a specific memory type, heap, custom pool, or total.

These are fast to calculate.
See functions: vmaGetHeapBudgets(), vmaGetPoolStatistics().
*/
typedef struct VmaStatistics
{
    /** \brief Number of `VkDeviceMemory` objects - Vulkan memory blocks allocated.
    */
    uint32_t blockCount;
    /** \brief Number of #VmaAllocation objects allocated.
    
    Dedicated allocations have their own blocks, so each one adds 1 to `allocationCount` as well as `blockCount`.
    */
    uint32_t allocationCount;
    /** \brief Number of bytes allocated in `VkDeviceMemory` blocks.
    
    \note To avoid confusion, please be aware that what Vulkan calls an "allocation" - a whole `VkDeviceMemory` object
    (e.g. as in `VkPhysicalDeviceLimits::maxMemoryAllocationCount`) is called a "block" in VMA, while VMA calls
    "allocation" a #VmaAllocation object that represents a memory region sub-allocated from such block, usually for a single buffer or image.
    */
    VkDeviceSize blockBytes;
    /** \brief Total number of bytes occupied by all #VmaAllocation objects.
    
    Always less or equal than `blockBytes`.
    Difference `(blockBytes - allocationBytes)` is the amount of memory allocated from Vulkan
    but unused by any #VmaAllocation.
    */
    VkDeviceSize allocationBytes;
} VmaStatistics;

/** \brief More detailed statistics than #VmaStatistics.

These are slower to calculate. Use for debugging purposes.
See functions: vmaCalculateStatistics(), vmaCalculatePoolStatistics().

Previous version of the statistics API provided averages, but they have been removed
because they can be easily calculated as:

\code
VkDeviceSize allocationSizeAvg = detailedStats.statistics.allocationBytes / detailedStats.statistics.allocationCount;
VkDeviceSize unusedBytes = detailedStats.statistics.blockBytes - detailedStats.statistics.allocationBytes;
VkDeviceSize unusedRangeSizeAvg = unusedBytes / detailedStats.unusedRangeCount;
\endcode
*/
typedef struct VmaDetailedStatistics
{
    /// Basic statistics.
    VmaStatistics statistics;
    /// Number of free ranges of memory between allocations.
    uint32_t unusedRangeCount;
    /// Smallest allocation size. `VK_WHOLE_SIZE` if there are 0 allocations.
    VkDeviceSize allocationSizeMin;
    /// Largest allocation size. 0 if there are 0 allocations.
    VkDeviceSize allocationSizeMax;
    /// Smallest empty range size. `VK_WHOLE_SIZE` if there are 0 empty ranges.
    VkDeviceSize unusedRangeSizeMin;
    /// Largest empty range size. 0 if there are 0 empty ranges.
    VkDeviceSize unusedRangeSizeMax;
} VmaDetailedStatistics;

/** \brief  General statistics from current state of the Allocator -
total memory usage across all memory heaps and types.

These are slower to calculate. Use for debugging purposes.
See function vmaCalculateStatistics().
*/
typedef struct VmaTotalStatistics
{
    VmaDetailedStatistics memoryType[VK_MAX_MEMORY_TYPES];
    VmaDetailedStatistics memoryHeap[VK_MAX_MEMORY_HEAPS];
    VmaDetailedStatistics total;
} VmaTotalStatistics;

/** \brief Statistics of current memory usage and available budget for a specific memory heap.

These are fast to calculate.
See function vmaGetHeapBudgets().
*/
typedef struct VmaBudget
{
    /** \brief Statistics fetched from the library.
    */
    VmaStatistics statistics;
    /** \brief Estimated current memory usage of the program, in bytes.

    Fetched from system using VK_EXT_memory_budget extension if enabled.

    It might be different than `statistics.blockBytes` (usually higher) due to additional implicit objects
    also occupying the memory, like swapchain, pipelines, descriptor heaps, command buffers, or
    `VkDeviceMemory` blocks allocated outside of this library, if any.
    */
    VkDeviceSize usage;
    /** \brief Estimated amount of memory available to the program, in bytes.

    Fetched from system using VK_EXT_memory_budget extension if enabled.

    It might be different (most probably smaller) than `VkMemoryHeap::size[heapIndex]` due to factors
    external to the program, decided by the operating system.
    Difference `budget - usage` is the amount of additional memory that can probably
    be allocated without problems. Exceeding the budget may result in various problems.
    */
    VkDeviceSize budget;
} VmaBudget;

/** @} */

/**
\addtogroup group_alloc
@{
*/

/** \brief Parameters of new #VmaAllocation.

To be used with functions like vmaCreateBuffer(), vmaCreateImage(), and many others.
*/
typedef struct VmaAllocationCreateInfo
{
    /// Use #VmaAllocationCreateFlagBits enum.
    VmaAllocationCreateFlags flags;
    /** \brief Intended usage of memory.

    You can leave #VMA_MEMORY_USAGE_UNKNOWN if you specify memory requirements in other way. \n
    If `pool` is not null, this member is ignored.
    */
    VmaMemoryUsage usage;
    /** \brief Flags that must be set in a Memory Type chosen for an allocation.

    Leave 0 if you specify memory requirements in other way. \n
    If `pool` is not null, this member is ignored.*/
    VkMemoryPropertyFlags requiredFlags;
    /** \brief Flags that preferably should be set in a memory type chosen for an allocation.

    Set to 0 if no additional flags are preferred. \n
    If `pool` is not null, this member is ignored. */
    VkMemoryPropertyFlags preferredFlags;
    /** \brief Bitmask containing one bit set for every memory type acceptable for this allocation.

    Value 0 is equivalent to `UINT32_MAX` - it means any memory type is accepted if
    it meets other requirements specified by this structure, with no further
    restrictions on memory type index. \n
    If `pool` is not null, this member is ignored.
    */
    uint32_t memoryTypeBits;
    /** \brief Pool that this allocation should be created in.

    Leave `VK_NULL_HANDLE` to allocate from default pool. If not null, members:
    `usage`, `requiredFlags`, `preferredFlags`, `memoryTypeBits` are ignored.
    */
    VmaPool VMA_NULLABLE pool;
    /** \brief Custom general-purpose pointer that will be stored in #VmaAllocation, can be read as VmaAllocationInfo::pUserData and changed using vmaSetAllocationUserData().

    If #VMA_ALLOCATION_CREATE_USER_DATA_COPY_STRING_BIT is used, it must be either
    null or pointer to a null-terminated string. The string will be then copied to
    internal buffer, so it doesn't need to be valid after allocation call.
    */
    void* VMA_NULLABLE pUserData;
    /** \brief A floating-point value between 0 and 1, indicating the priority of the allocation relative to other memory allocations.

    It is used only when #VMA_ALLOCATOR_CREATE_EXT_MEMORY_PRIORITY_BIT flag was used during creation of the #VmaAllocator object
    and this allocation ends up as dedicated or is explicitly forced as dedicated using #VMA_ALLOCATION_CREATE_DEDICATED_MEMORY_BIT.
    Otherwise, it has the priority of a memory block where it is placed and this variable is ignored.
    */
    float priority;
} VmaAllocationCreateInfo;

/// Describes parameter of created #VmaPool.
typedef struct VmaPoolCreateInfo
{
    /** \brief Vulkan memory type index to allocate this pool from.
    */
    uint32_t memoryTypeIndex;
    /** \brief Use combination of #VmaPoolCreateFlagBits.
    */
    VmaPoolCreateFlags flags;
    /** \brief Size of a single `VkDeviceMemory` block to be allocated as part of this pool, in bytes. Optional.

    Specify nonzero to set explicit, constant size of memory blocks used by this
    pool.

    Leave 0 to use default and let the library manage block sizes automatically.
    Sizes of particular blocks may vary.
    In this case, the pool will also support dedicated allocations.
    */
    VkDeviceSize blockSize;
    /** \brief Minimum number of blocks to be always allocated in this pool, even if they stay empty.

    Set to 0 to have no preallocated blocks and allow the pool be completely empty.
    */
    size_t minBlockCount;
    /** \brief Maximum number of blocks that can be allocated in this pool. Optional.

    Set to 0 to use default, which is `SIZE_MAX`, which means no limit.

    Set to same value as VmaPoolCreateInfo::minBlockCount to have fixed amount of memory allocated
    throughout whole lifetime of this pool.
    */
    size_t maxBlockCount;
    /** \brief A floating-point value between 0 and 1, indicating the priority of the allocations in this pool relative to other memory allocations.

    It is used only when #VMA_ALLOCATOR_CREATE_EXT_MEMORY_PRIORITY_BIT flag was used during creation of the #VmaAllocator object.
    Otherwise, this variable is ignored.
    */
    float priority;
    /** \brief Additional minimum alignment to be used for all allocations created from this pool. Can be 0.

    Leave 0 (default) not to impose any additional alignment. If not 0, it must be a power of two.
    It can be useful in cases where alignment returned by Vulkan by functions like `vkGetBufferMemoryRequirements` is not enough,
    e.g. when doing interop with OpenGL.
    */
    VkDeviceSize minAllocationAlignment;
    /** \brief Additional `pNext` chain to be attached to `VkMemoryAllocateInfo` used for every allocation made by this pool. Optional.

    Optional, can be null. If not null, it must point to a `pNext` chain of structures that can be attached to `VkMemoryAllocateInfo`.
    It can be useful for special needs such as adding `VkExportMemoryAllocateInfoKHR`.
    Structures pointed by this member must remain alive and unchanged for the whole lifetime of the custom pool.

    Please note that some structures, e.g. `VkMemoryPriorityAllocateInfoEXT`, `VkMemoryDedicatedAllocateInfoKHR`,
    can be attached automatically by this library when using other, more convenient of its features.
    */
    void* VMA_NULLABLE pMemoryAllocateNext;
} VmaPoolCreateInfo;

/** @} */

/**
\addtogroup group_alloc
@{
*/

/// Parameters of #VmaAllocation objects, that can be retrieved using function vmaGetAllocationInfo().
typedef struct VmaAllocationInfo
{
    /** \brief Memory type index that this allocation was allocated from.

    It never changes.
    */
    uint32_t memoryType;
    /** \brief Handle to Vulkan memory object.

    Same memory object can be shared by multiple allocations.

    It can change after the allocation is moved during \ref defragmentation.
    */
    VkDeviceMemory VMA_NULLABLE_NON_DISPATCHABLE deviceMemory;
    /** \brief Offset in `VkDeviceMemory` object to the beginning of this allocation, in bytes. `(deviceMemory, offset)` pair is unique to this allocation.

    You usually don't need to use this offset. If you create a buffer or an image together with the allocation using e.g. function
    vmaCreateBuffer(), vmaCreateImage(), functions that operate on these resources refer to the beginning of the buffer or image,
    not entire device memory block. Functions like vmaMapMemory(), vmaBindBufferMemory() also refer to the beginning of the allocation
    and apply this offset automatically.

    It can change after the allocation is moved during \ref defragmentation.
    */
    VkDeviceSize offset;
    /** \brief Size of this allocation, in bytes.

    It never changes.

    \note Allocation size returned in this variable may be greater than the size
    requested for the resource e.g. as `VkBufferCreateInfo::size`. Whole size of the
    allocation is accessible for operations on memory e.g. using a pointer after
    mapping with vmaMapMemory(), but operations on the resource e.g. using
    `vkCmdCopyBuffer` must be limited to the size of the resource.
    */
    VkDeviceSize size;
    /** \brief Pointer to the beginning of this allocation as mapped data.

    If the allocation hasn't been mapped using vmaMapMemory() and hasn't been
    created with #VMA_ALLOCATION_CREATE_MAPPED_BIT flag, this value is null.

    It can change after call to vmaMapMemory(), vmaUnmapMemory().
    It can also change after the allocation is moved during \ref defragmentation.
    */
    void* VMA_NULLABLE pMappedData;
    /** \brief Custom general-purpose pointer that was passed as VmaAllocationCreateInfo::pUserData or set using vmaSetAllocationUserData().

    It can change after call to vmaSetAllocationUserData() for this allocation.
    */
    void* VMA_NULLABLE pUserData;
    /** \brief Custom allocation name that was set with vmaSetAllocationName().
    
    It can change after call to vmaSetAllocationName() for this allocation.
    
    Another way to set custom name is to pass it in VmaAllocationCreateInfo::pUserData with
    additional flag #VMA_ALLOCATION_CREATE_USER_DATA_COPY_STRING_BIT set [DEPRECATED].
    */
    const char* VMA_NULLABLE pName;
} VmaAllocationInfo;

/** \brief Parameters for defragmentation.

To be used with function vmaBeginDefragmentation().
*/
typedef struct VmaDefragmentationInfo
{
    /// \brief Use combination of #VmaDefragmentationFlagBits.
    VmaDefragmentationFlags flags;
    /** \brief Custom pool to be defragmented.

    If null then default pools will undergo defragmentation process.
    */
    VmaPool VMA_NULLABLE pool;
    /** \brief Maximum numbers of bytes that can be copied during single pass, while moving allocations to different places.

    `0` means no limit.
    */
    VkDeviceSize maxBytesPerPass;
    /** \brief Maximum number of allocations that can be moved during single pass to a different place.

    `0` means no limit.
    */
    uint32_t maxAllocationsPerPass;
} VmaDefragmentationInfo;

/// Single move of an allocation to be done for defragmentation.
typedef struct VmaDefragmentationMove
{
    /// Operation to be performed on the allocation by vmaEndDefragmentationPass(). Default value is #VMA_DEFRAGMENTATION_MOVE_OPERATION_COPY. You can modify it.
    VmaDefragmentationMoveOperation operation;
    /// Allocation that should be moved.
    VmaAllocation VMA_NOT_NULL srcAllocation;
    /** \brief Temporary allocation pointing to destination memory that will replace `srcAllocation`.
    
    \warning Do not store this allocation in your data structures! It exists only temporarily, for the duration of the defragmentation pass,
    to be used for binding new buffer/image to the destination memory using e.g. vmaBindBufferMemory().
    vmaEndDefragmentationPass() will destroy it and make `srcAllocation` point to this memory.
    */
    VmaAllocation VMA_NOT_NULL dstTmpAllocation;
} VmaDefragmentationMove;

/** \brief Parameters for incremental defragmentation steps.

To be used with function vmaBeginDefragmentationPass().
*/
typedef struct VmaDefragmentationPassMoveInfo
{
    /// Number of elements in the `pMoves` array.
    uint32_t moveCount;
    /** \brief Array of moves to be performed by the user in the current defragmentation pass.
    
    Pointer to an array of `moveCount` elements, owned by VMA, created in vmaBeginDefragmentationPass(), destroyed in vmaEndDefragmentationPass().

    For each element, you should:
    
    1. Create a new buffer/image in the place pointed by VmaDefragmentationMove::dstMemory + VmaDefragmentationMove::dstOffset.
    2. Copy data from the VmaDefragmentationMove::srcAllocation e.g. using `vkCmdCopyBuffer`, `vkCmdCopyImage`.
    3. Make sure these commands finished executing on the GPU.
    4. Destroy the old buffer/image.
    
    Only then you can finish defragmentation pass by calling vmaEndDefragmentationPass().
    After this call, the allocation will point to the new place in memory.

    Alternatively, if you cannot move specific allocation, you can set VmaDefragmentationMove::operation to #VMA_DEFRAGMENTATION_MOVE_OPERATION_IGNORE.

    Alternatively, if you decide you want to completely remove the allocation:

    1. Destroy its buffer/image.
    2. Set VmaDefragmentationMove::operation to #VMA_DEFRAGMENTATION_MOVE_OPERATION_DESTROY.

    Then, after vmaEndDefragmentationPass() the allocation will be freed.
    */
    VmaDefragmentationMove* VMA_NULLABLE VMA_LEN_IF_NOT_NULL(moveCount) pMoves;
} VmaDefragmentationPassMoveInfo;

/// Statistics returned for defragmentation process in function vmaEndDefragmentation().
typedef struct VmaDefragmentationStats
{
    /// Total number of bytes that have been copied while moving allocations to different places.
    VkDeviceSize bytesMoved;
    /// Total number of bytes that have been released to the system by freeing empty `VkDeviceMemory` objects.
    VkDeviceSize bytesFreed;
    /// Number of allocations that have been moved to different places.
    uint32_t allocationsMoved;
    /// Number of empty `VkDeviceMemory` objects that have been released to the system.
    uint32_t deviceMemoryBlocksFreed;
} VmaDefragmentationStats;

/** @} */

/**
\addtogroup group_virtual
@{
*/

/// Parameters of created #VmaVirtualBlock object to be passed to vmaCreateVirtualBlock().
typedef struct VmaVirtualBlockCreateInfo
{
    /** \brief Total size of the virtual block.

    Sizes can be expressed in bytes or any units you want as long as you are consistent in using them.
    For example, if you allocate from some array of structures, 1 can mean single instance of entire structure.
    */
    VkDeviceSize size;

    /** \brief Use combination of #VmaVirtualBlockCreateFlagBits.
    */
    VmaVirtualBlockCreateFlags flags;

    /** \brief Custom CPU memory allocation callbacks. Optional.

    Optional, can be null. When specified, they will be used for all CPU-side memory allocations.
    */
    const VkAllocationCallbacks* VMA_NULLABLE pAllocationCallbacks;
} VmaVirtualBlockCreateInfo;

/// Parameters of created virtual allocation to be passed to vmaVirtualAllocate().
typedef struct VmaVirtualAllocationCreateInfo
{
    /** \brief Size of the allocation.

    Cannot be zero.
    */
    VkDeviceSize size;
    /** \brief Required alignment of the allocation. Optional.

    Must be power of two. Special value 0 has the same meaning as 1 - means no special alignment is required, so allocation can start at any offset.
    */
    VkDeviceSize alignment;
    /** \brief Use combination of #VmaVirtualAllocationCreateFlagBits.
    */
    VmaVirtualAllocationCreateFlags flags;
    /** \brief Custom pointer to be associated with the allocation. Optional.

    It can be any value and can be used for user-defined purposes. It can be fetched or changed later.
    */
    void* VMA_NULLABLE pUserData;
} VmaVirtualAllocationCreateInfo;

/// Parameters of an existing virtual allocation, returned by vmaGetVirtualAllocationInfo().
typedef struct VmaVirtualAllocationInfo
{
    /** \brief Offset of the allocation.
     
    Offset at which the allocation was made.
    */
    VkDeviceSize offset;
    /** \brief Size of the allocation.

    Same value as passed in VmaVirtualAllocationCreateInfo::size.
    */
    VkDeviceSize size;
    /** \brief Custom pointer associated with the allocation.

    Same value as passed in VmaVirtualAllocationCreateInfo::pUserData or to vmaSetVirtualAllocationUserData().
    */
    void* VMA_NULLABLE pUserData;
} VmaVirtualAllocationInfo;

/** @} */

#endif // _VMA_DATA_TYPES_DECLARATIONS

#ifndef _VMA_FUNCTION_HEADERS

/**
\addtogroup group_init
@{
*/

/// Creates #VmaAllocator object.
VMA_CALL_PRE VkResult VMA_CALL_POST vmaCreateAllocator(
    const VmaAllocatorCreateInfo* VMA_NOT_NULL pCreateInfo,
    VmaAllocator VMA_NULLABLE* VMA_NOT_NULL pAllocator);

/// Destroys allocator object.
VMA_CALL_PRE void VMA_CALL_POST vmaDestroyAllocator(
    VmaAllocator VMA_NULLABLE allocator);

/** \brief Returns information about existing #VmaAllocator object - handle to Vulkan device etc.

It might be useful if you want to keep just the #VmaAllocator handle and fetch other required handles to
`VkPhysicalDevice`, `VkDevice` etc. every time using this function.
*/
VMA_CALL_PRE void VMA_CALL_POST vmaGetAllocatorInfo(
    VmaAllocator VMA_NOT_NULL allocator,
    VmaAllocatorInfo* VMA_NOT_NULL pAllocatorInfo);

/**
PhysicalDeviceProperties are fetched from physicalDevice by the allocator.
You can access it here, without fetching it again on your own.
*/
VMA_CALL_PRE void VMA_CALL_POST vmaGetPhysicalDeviceProperties(
    VmaAllocator VMA_NOT_NULL allocator,
    const VkPhysicalDeviceProperties* VMA_NULLABLE* VMA_NOT_NULL ppPhysicalDeviceProperties);

/**
PhysicalDeviceMemoryProperties are fetched from physicalDevice by the allocator.
You can access it here, without fetching it again on your own.
*/
VMA_CALL_PRE void VMA_CALL_POST vmaGetMemoryProperties(
    VmaAllocator VMA_NOT_NULL allocator,
    const VkPhysicalDeviceMemoryProperties* VMA_NULLABLE* VMA_NOT_NULL ppPhysicalDeviceMemoryProperties);

/**
\brief Given Memory Type Index, returns Property Flags of this memory type.

This is just a convenience function. Same information can be obtained using
vmaGetMemoryProperties().
*/
VMA_CALL_PRE void VMA_CALL_POST vmaGetMemoryTypeProperties(
    VmaAllocator VMA_NOT_NULL allocator,
    uint32_t memoryTypeIndex,
    VkMemoryPropertyFlags* VMA_NOT_NULL pFlags);

/** \brief Sets index of the current frame.
*/
VMA_CALL_PRE void VMA_CALL_POST vmaSetCurrentFrameIndex(
    VmaAllocator VMA_NOT_NULL allocator,
    uint32_t frameIndex);

/** @} */

/**
\addtogroup group_stats
@{
*/

/** \brief Retrieves statistics from current state of the Allocator.

This function is called "calculate" not "get" because it has to traverse all
internal data structures, so it may be quite slow. Use it for debugging purposes.
For faster but more brief statistics suitable to be called every frame or every allocation,
use vmaGetHeapBudgets().

Note that when using allocator from multiple threads, returned information may immediately
become outdated.
*/
VMA_CALL_PRE void VMA_CALL_POST vmaCalculateStatistics(
    VmaAllocator VMA_NOT_NULL allocator,
    VmaTotalStatistics* VMA_NOT_NULL pStats);

/** \brief Retrieves information about current memory usage and budget for all memory heaps.

\param allocator
\param[out] pBudgets Must point to array with number of elements at least equal to number of memory heaps in physical device used.

This function is called "get" not "calculate" because it is very fast, suitable to be called
every frame or every allocation. For more detailed statistics use vmaCalculateStatistics().

Note that when using allocator from multiple threads, returned information may immediately
become outdated.
*/
VMA_CALL_PRE void VMA_CALL_POST vmaGetHeapBudgets(
    VmaAllocator VMA_NOT_NULL allocator,
    VmaBudget* VMA_NOT_NULL VMA_LEN_IF_NOT_NULL("VkPhysicalDeviceMemoryProperties::memoryHeapCount") pBudgets);

/** @} */

/**
\addtogroup group_alloc
@{
*/

/**
\brief Helps to find memoryTypeIndex, given memoryTypeBits and VmaAllocationCreateInfo.

This algorithm tries to find a memory type that:

- Is allowed by memoryTypeBits.
- Contains all the flags from pAllocationCreateInfo->requiredFlags.
- Matches intended usage.
- Has as many flags from pAllocationCreateInfo->preferredFlags as possible.

\return Returns VK_ERROR_FEATURE_NOT_PRESENT if not found. Receiving such result
from this function or any other allocating function probably means that your
device doesn't support any memory type with requested features for the specific
type of resource you want to use it for. Please check parameters of your
resource, like image layout (OPTIMAL versus LINEAR) or mip level count.
*/
VMA_CALL_PRE VkResult VMA_CALL_POST vmaFindMemoryTypeIndex(
    VmaAllocator VMA_NOT_NULL allocator,
    uint32_t memoryTypeBits,
    const VmaAllocationCreateInfo* VMA_NOT_NULL pAllocationCreateInfo,
    uint32_t* VMA_NOT_NULL pMemoryTypeIndex);

/**
\brief Helps to find memoryTypeIndex, given VkBufferCreateInfo and VmaAllocationCreateInfo.

It can be useful e.g. to determine value to be used as VmaPoolCreateInfo::memoryTypeIndex.
It internally creates a temporary, dummy buffer that never has memory bound.
*/
VMA_CALL_PRE VkResult VMA_CALL_POST vmaFindMemoryTypeIndexForBufferInfo(
    VmaAllocator VMA_NOT_NULL allocator,
    const VkBufferCreateInfo* VMA_NOT_NULL pBufferCreateInfo,
    const VmaAllocationCreateInfo* VMA_NOT_NULL pAllocationCreateInfo,
    uint32_t* VMA_NOT_NULL pMemoryTypeIndex);

/**
\brief Helps to find memoryTypeIndex, given VkImageCreateInfo and VmaAllocationCreateInfo.

It can be useful e.g. to determine value to be used as VmaPoolCreateInfo::memoryTypeIndex.
It internally creates a temporary, dummy image that never has memory bound.
*/
VMA_CALL_PRE VkResult VMA_CALL_POST vmaFindMemoryTypeIndexForImageInfo(
    VmaAllocator VMA_NOT_NULL allocator,
    const VkImageCreateInfo* VMA_NOT_NULL pImageCreateInfo,
    const VmaAllocationCreateInfo* VMA_NOT_NULL pAllocationCreateInfo,
    uint32_t* VMA_NOT_NULL pMemoryTypeIndex);

/** \brief Allocates Vulkan device memory and creates #VmaPool object.

\param allocator Allocator object.
\param pCreateInfo Parameters of pool to create.
\param[out] pPool Handle to created pool.
*/
VMA_CALL_PRE VkResult VMA_CALL_POST vmaCreatePool(
    VmaAllocator VMA_NOT_NULL allocator,
    const VmaPoolCreateInfo* VMA_NOT_NULL pCreateInfo,
    VmaPool VMA_NULLABLE* VMA_NOT_NULL pPool);

/** \brief Destroys #VmaPool object and frees Vulkan device memory.
*/
VMA_CALL_PRE void VMA_CALL_POST vmaDestroyPool(
    VmaAllocator VMA_NOT_NULL allocator,
    VmaPool VMA_NULLABLE pool);

/** @} */

/**
\addtogroup group_stats
@{
*/

/** \brief Retrieves statistics of existing #VmaPool object.

\param allocator Allocator object.
\param pool Pool object.
\param[out] pPoolStats Statistics of specified pool.
*/
VMA_CALL_PRE void VMA_CALL_POST vmaGetPoolStatistics(
    VmaAllocator VMA_NOT_NULL allocator,
    VmaPool VMA_NOT_NULL pool,
    VmaStatistics* VMA_NOT_NULL pPoolStats);

/** \brief Retrieves detailed statistics of existing #VmaPool object.

\param allocator Allocator object.
\param pool Pool object.
\param[out] pPoolStats Statistics of specified pool.
*/
VMA_CALL_PRE void VMA_CALL_POST vmaCalculatePoolStatistics(
    VmaAllocator VMA_NOT_NULL allocator,
    VmaPool VMA_NOT_NULL pool,
    VmaDetailedStatistics* VMA_NOT_NULL pPoolStats);

/** @} */

/**
\addtogroup group_alloc
@{
*/

/** \brief Checks magic number in margins around all allocations in given memory pool in search for corruptions.

Corruption detection is enabled only when `VMA_DEBUG_DETECT_CORRUPTION` macro is defined to nonzero,
`VMA_DEBUG_MARGIN` is defined to nonzero and the pool is created in memory type that is
`HOST_VISIBLE` and `HOST_COHERENT`. For more information, see [Corruption detection](@ref debugging_memory_usage_corruption_detection).

Possible return values:

- `VK_ERROR_FEATURE_NOT_PRESENT` - corruption detection is not enabled for specified pool.
- `VK_SUCCESS` - corruption detection has been performed and succeeded.
- `VK_ERROR_UNKNOWN` - corruption detection has been performed and found memory corruptions around one of the allocations.
  `VMA_ASSERT` is also fired in that case.
- Other value: Error returned by Vulkan, e.g. memory mapping failure.
*/
VMA_CALL_PRE VkResult VMA_CALL_POST vmaCheckPoolCorruption(
    VmaAllocator VMA_NOT_NULL allocator,
    VmaPool VMA_NOT_NULL pool);

/** \brief Retrieves name of a custom pool.

After the call `ppName` is either null or points to an internally-owned null-terminated string
containing name of the pool that was previously set. The pointer becomes invalid when the pool is
destroyed or its name is changed using vmaSetPoolName().
*/
VMA_CALL_PRE void VMA_CALL_POST vmaGetPoolName(
    VmaAllocator VMA_NOT_NULL allocator,
    VmaPool VMA_NOT_NULL pool,
    const char* VMA_NULLABLE* VMA_NOT_NULL ppName);

/** \brief Sets name of a custom pool.

`pName` can be either null or pointer to a null-terminated string with new name for the pool.
Function makes internal copy of the string, so it can be changed or freed immediately after this call.
*/
VMA_CALL_PRE void VMA_CALL_POST vmaSetPoolName(
    VmaAllocator VMA_NOT_NULL allocator,
    VmaPool VMA_NOT_NULL pool,
    const char* VMA_NULLABLE pName);

/** \brief General purpose memory allocation.

\param allocator
\param pVkMemoryRequirements
\param pCreateInfo
\param[out] pAllocation Handle to allocated memory.
\param[out] pAllocationInfo Optional. Information about allocated memory. It can be later fetched using function vmaGetAllocationInfo().

You should free the memory using vmaFreeMemory() or vmaFreeMemoryPages().

It is recommended to use vmaAllocateMemoryForBuffer(), vmaAllocateMemoryForImage(),
vmaCreateBuffer(), vmaCreateImage() instead whenever possible.
*/
VMA_CALL_PRE VkResult VMA_CALL_POST vmaAllocateMemory(
    VmaAllocator VMA_NOT_NULL allocator,
    const VkMemoryRequirements* VMA_NOT_NULL pVkMemoryRequirements,
    const VmaAllocationCreateInfo* VMA_NOT_NULL pCreateInfo,
    VmaAllocation VMA_NULLABLE* VMA_NOT_NULL pAllocation,
    VmaAllocationInfo* VMA_NULLABLE pAllocationInfo);

/** \brief General purpose memory allocation for multiple allocation objects at once.

\param allocator Allocator object.
\param pVkMemoryRequirements Memory requirements for each allocation.
\param pCreateInfo Creation parameters for each allocation.
\param allocationCount Number of allocations to make.
\param[out] pAllocations Pointer to array that will be filled with handles to created allocations.
\param[out] pAllocationInfo Optional. Pointer to array that will be filled with parameters of created allocations.

You should free the memory using vmaFreeMemory() or vmaFreeMemoryPages().

Word "pages" is just a suggestion to use this function to allocate pieces of memory needed for sparse binding.
It is just a general purpose allocation function able to make multiple allocations at once.
It may be internally optimized to be more efficient than calling vmaAllocateMemory() `allocationCount` times.

All allocations are made using same parameters. All of them are created out of the same memory pool and type.
If any allocation fails, all allocations already made within this function call are also freed, so that when
returned result is not `VK_SUCCESS`, `pAllocation` array is always entirely filled with `VK_NULL_HANDLE`.
*/
VMA_CALL_PRE VkResult VMA_CALL_POST vmaAllocateMemoryPages(
    VmaAllocator VMA_NOT_NULL allocator,
    const VkMemoryRequirements* VMA_NOT_NULL VMA_LEN_IF_NOT_NULL(allocationCount) pVkMemoryRequirements,
    const VmaAllocationCreateInfo* VMA_NOT_NULL VMA_LEN_IF_NOT_NULL(allocationCount) pCreateInfo,
    size_t allocationCount,
    VmaAllocation VMA_NULLABLE* VMA_NOT_NULL VMA_LEN_IF_NOT_NULL(allocationCount) pAllocations,
    VmaAllocationInfo* VMA_NULLABLE VMA_LEN_IF_NOT_NULL(allocationCount) pAllocationInfo);

/** \brief Allocates memory suitable for given `VkBuffer`.

\param allocator
\param buffer
\param pCreateInfo
\param[out] pAllocation Handle to allocated memory.
\param[out] pAllocationInfo Optional. Information about allocated memory. It can be later fetched using function vmaGetAllocationInfo().

It only creates #VmaAllocation. To bind the memory to the buffer, use vmaBindBufferMemory().

This is a special-purpose function. In most cases you should use vmaCreateBuffer().

You must free the allocation using vmaFreeMemory() when no longer needed.
*/
VMA_CALL_PRE VkResult VMA_CALL_POST vmaAllocateMemoryForBuffer(
    VmaAllocator VMA_NOT_NULL allocator,
    VkBuffer VMA_NOT_NULL_NON_DISPATCHABLE buffer,
    const VmaAllocationCreateInfo* VMA_NOT_NULL pCreateInfo,
    VmaAllocation VMA_NULLABLE* VMA_NOT_NULL pAllocation,
    VmaAllocationInfo* VMA_NULLABLE pAllocationInfo);

/** \brief Allocates memory suitable for given `VkImage`.

\param allocator
\param image
\param pCreateInfo
\param[out] pAllocation Handle to allocated memory.
\param[out] pAllocationInfo Optional. Information about allocated memory. It can be later fetched using function vmaGetAllocationInfo().

It only creates #VmaAllocation. To bind the memory to the buffer, use vmaBindImageMemory().

This is a special-purpose function. In most cases you should use vmaCreateImage().

You must free the allocation using vmaFreeMemory() when no longer needed.
*/
VMA_CALL_PRE VkResult VMA_CALL_POST vmaAllocateMemoryForImage(
    VmaAllocator VMA_NOT_NULL allocator,
    VkImage VMA_NOT_NULL_NON_DISPATCHABLE image,
    const VmaAllocationCreateInfo* VMA_NOT_NULL pCreateInfo,
    VmaAllocation VMA_NULLABLE* VMA_NOT_NULL pAllocation,
    VmaAllocationInfo* VMA_NULLABLE pAllocationInfo);

/** \brief Frees memory previously allocated using vmaAllocateMemory(), vmaAllocateMemoryForBuffer(), or vmaAllocateMemoryForImage().

Passing `VK_NULL_HANDLE` as `allocation` is valid. Such function call is just skipped.
*/
VMA_CALL_PRE void VMA_CALL_POST vmaFreeMemory(
    VmaAllocator VMA_NOT_NULL allocator,
    const VmaAllocation VMA_NULLABLE allocation);

/** \brief Frees memory and destroys multiple allocations.

Word "pages" is just a suggestion to use this function to free pieces of memory used for sparse binding.
It is just a general purpose function to free memory and destroy allocations made using e.g. vmaAllocateMemory(),
vmaAllocateMemoryPages() and other functions.
It may be internally optimized to be more efficient than calling vmaFreeMemory() `allocationCount` times.

Allocations in `pAllocations` array can come from any memory pools and types.
Passing `VK_NULL_HANDLE` as elements of `pAllocations` array is valid. Such entries are just skipped.
*/
VMA_CALL_PRE void VMA_CALL_POST vmaFreeMemoryPages(
    VmaAllocator VMA_NOT_NULL allocator,
    size_t allocationCount,
    const VmaAllocation VMA_NULLABLE* VMA_NOT_NULL VMA_LEN_IF_NOT_NULL(allocationCount) pAllocations);

/** \brief Returns current information about specified allocation.

Current paramteres of given allocation are returned in `pAllocationInfo`.

Although this function doesn't lock any mutex, so it should be quite efficient,
you should avoid calling it too often.
You can retrieve same VmaAllocationInfo structure while creating your resource, from function
vmaCreateBuffer(), vmaCreateImage(). You can remember it if you are sure parameters don't change
(e.g. due to defragmentation).
*/
VMA_CALL_PRE void VMA_CALL_POST vmaGetAllocationInfo(
    VmaAllocator VMA_NOT_NULL allocator,
    VmaAllocation VMA_NOT_NULL allocation,
    VmaAllocationInfo* VMA_NOT_NULL pAllocationInfo);

/** \brief Sets pUserData in given allocation to new value.

The value of pointer `pUserData` is copied to allocation's `pUserData`.
It is opaque, so you can use it however you want - e.g.
as a pointer, ordinal number or some handle to you own data.
*/
VMA_CALL_PRE void VMA_CALL_POST vmaSetAllocationUserData(
    VmaAllocator VMA_NOT_NULL allocator,
    VmaAllocation VMA_NOT_NULL allocation,
    void* VMA_NULLABLE pUserData);

/** \brief Sets pName in given allocation to new value.

`pName` must be either null, or pointer to a null-terminated string. The function
makes local copy of the string and sets it as allocation's `pName`. String
passed as pName doesn't need to be valid for whole lifetime of the allocation -
you can free it after this call. String previously pointed by allocation's
`pName` is freed from memory.
*/
VMA_CALL_PRE void VMA_CALL_POST vmaSetAllocationName(
    VmaAllocator VMA_NOT_NULL allocator,
    VmaAllocation VMA_NOT_NULL allocation,
    const char* VMA_NULLABLE pName);

/**
\brief Given an allocation, returns Property Flags of its memory type.

This is just a convenience function. Same information can be obtained using
vmaGetAllocationInfo() + vmaGetMemoryProperties().
*/
VMA_CALL_PRE void VMA_CALL_POST vmaGetAllocationMemoryProperties(
    VmaAllocator VMA_NOT_NULL allocator,
    VmaAllocation VMA_NOT_NULL allocation,
    VkMemoryPropertyFlags* VMA_NOT_NULL pFlags);

/** \brief Maps memory represented by given allocation and returns pointer to it.

Maps memory represented by given allocation to make it accessible to CPU code.
When succeeded, `*ppData` contains pointer to first byte of this memory.

\warning
If the allocation is part of a bigger `VkDeviceMemory` block, returned pointer is
correctly offsetted to the beginning of region assigned to this particular allocation.
Unlike the result of `vkMapMemory`, it points to the allocation, not to the beginning of the whole block.
You should not add VmaAllocationInfo::offset to it!

Mapping is internally reference-counted and synchronized, so despite raw Vulkan
function `vkMapMemory()` cannot be used to map same block of `VkDeviceMemory`
multiple times simultaneously, it is safe to call this function on allocations
assigned to the same memory block. Actual Vulkan memory will be mapped on first
mapping and unmapped on last unmapping.

If the function succeeded, you must call vmaUnmapMemory() to unmap the
allocation when mapping is no longer needed or before freeing the allocation, at
the latest.

It also safe to call this function multiple times on the same allocation. You
must call vmaUnmapMemory() same number of times as you called vmaMapMemory().

It is also safe to call this function on allocation created with
#VMA_ALLOCATION_CREATE_MAPPED_BIT flag. Its memory stays mapped all the time.
You must still call vmaUnmapMemory() same number of times as you called
vmaMapMemory(). You must not call vmaUnmapMemory() additional time to free the
"0-th" mapping made automatically due to #VMA_ALLOCATION_CREATE_MAPPED_BIT flag.

This function fails when used on allocation made in memory type that is not
`HOST_VISIBLE`.

This function doesn't automatically flush or invalidate caches.
If the allocation is made from a memory types that is not `HOST_COHERENT`,
you also need to use vmaInvalidateAllocation() / vmaFlushAllocation(), as required by Vulkan specification.
*/
VMA_CALL_PRE VkResult VMA_CALL_POST vmaMapMemory(
    VmaAllocator VMA_NOT_NULL allocator,
    VmaAllocation VMA_NOT_NULL allocation,
    void* VMA_NULLABLE* VMA_NOT_NULL ppData);

/** \brief Unmaps memory represented by given allocation, mapped previously using vmaMapMemory().

For details, see description of vmaMapMemory().

This function doesn't automatically flush or invalidate caches.
If the allocation is made from a memory types that is not `HOST_COHERENT`,
you also need to use vmaInvalidateAllocation() / vmaFlushAllocation(), as required by Vulkan specification.
*/
VMA_CALL_PRE void VMA_CALL_POST vmaUnmapMemory(
    VmaAllocator VMA_NOT_NULL allocator,
    VmaAllocation VMA_NOT_NULL allocation);

/** \brief Flushes memory of given allocation.

Calls `vkFlushMappedMemoryRanges()` for memory associated with given range of given allocation.
It needs to be called after writing to a mapped memory for memory types that are not `HOST_COHERENT`.
Unmap operation doesn't do that automatically.

- `offset` must be relative to the beginning of allocation.
- `size` can be `VK_WHOLE_SIZE`. It means all memory from `offset` the the end of given allocation.
- `offset` and `size` don't have to be aligned.
  They are internally rounded down/up to multiply of `nonCoherentAtomSize`.
- If `size` is 0, this call is ignored.
- If memory type that the `allocation` belongs to is not `HOST_VISIBLE` or it is `HOST_COHERENT`,
  this call is ignored.

Warning! `offset` and `size` are relative to the contents of given `allocation`.
If you mean whole allocation, you can pass 0 and `VK_WHOLE_SIZE`, respectively.
Do not pass allocation's offset as `offset`!!!

This function returns the `VkResult` from `vkFlushMappedMemoryRanges` if it is
called, otherwise `VK_SUCCESS`.
*/
VMA_CALL_PRE VkResult VMA_CALL_POST vmaFlushAllocation(
    VmaAllocator VMA_NOT_NULL allocator,
    VmaAllocation VMA_NOT_NULL allocation,
    VkDeviceSize offset,
    VkDeviceSize size);

/** \brief Invalidates memory of given allocation.

Calls `vkInvalidateMappedMemoryRanges()` for memory associated with given range of given allocation.
It needs to be called before reading from a mapped memory for memory types that are not `HOST_COHERENT`.
Map operation doesn't do that automatically.

- `offset` must be relative to the beginning of allocation.
- `size` can be `VK_WHOLE_SIZE`. It means all memory from `offset` the the end of given allocation.
- `offset` and `size` don't have to be aligned.
  They are internally rounded down/up to multiply of `nonCoherentAtomSize`.
- If `size` is 0, this call is ignored.
- If memory type that the `allocation` belongs to is not `HOST_VISIBLE` or it is `HOST_COHERENT`,
  this call is ignored.

Warning! `offset` and `size` are relative to the contents of given `allocation`.
If you mean whole allocation, you can pass 0 and `VK_WHOLE_SIZE`, respectively.
Do not pass allocation's offset as `offset`!!!

This function returns the `VkResult` from `vkInvalidateMappedMemoryRanges` if
it is called, otherwise `VK_SUCCESS`.
*/
VMA_CALL_PRE VkResult VMA_CALL_POST vmaInvalidateAllocation(
    VmaAllocator VMA_NOT_NULL allocator,
    VmaAllocation VMA_NOT_NULL allocation,
    VkDeviceSize offset,
    VkDeviceSize size);

/** \brief Flushes memory of given set of allocations.

Calls `vkFlushMappedMemoryRanges()` for memory associated with given ranges of given allocations.
For more information, see documentation of vmaFlushAllocation().

\param allocator
\param allocationCount
\param allocations
\param offsets If not null, it must point to an array of offsets of regions to flush, relative to the beginning of respective allocations. Null means all ofsets are zero.
\param sizes If not null, it must point to an array of sizes of regions to flush in respective allocations. Null means `VK_WHOLE_SIZE` for all allocations.

This function returns the `VkResult` from `vkFlushMappedMemoryRanges` if it is
called, otherwise `VK_SUCCESS`.
*/
VMA_CALL_PRE VkResult VMA_CALL_POST vmaFlushAllocations(
    VmaAllocator VMA_NOT_NULL allocator,
    uint32_t allocationCount,
    const VmaAllocation VMA_NOT_NULL* VMA_NULLABLE VMA_LEN_IF_NOT_NULL(allocationCount) allocations,
    const VkDeviceSize* VMA_NULLABLE VMA_LEN_IF_NOT_NULL(allocationCount) offsets,
    const VkDeviceSize* VMA_NULLABLE VMA_LEN_IF_NOT_NULL(allocationCount) sizes);

/** \brief Invalidates memory of given set of allocations.

Calls `vkInvalidateMappedMemoryRanges()` for memory associated with given ranges of given allocations.
For more information, see documentation of vmaInvalidateAllocation().

\param allocator
\param allocationCount
\param allocations
\param offsets If not null, it must point to an array of offsets of regions to flush, relative to the beginning of respective allocations. Null means all ofsets are zero.
\param sizes If not null, it must point to an array of sizes of regions to flush in respective allocations. Null means `VK_WHOLE_SIZE` for all allocations.

This function returns the `VkResult` from `vkInvalidateMappedMemoryRanges` if it is
called, otherwise `VK_SUCCESS`.
*/
VMA_CALL_PRE VkResult VMA_CALL_POST vmaInvalidateAllocations(
    VmaAllocator VMA_NOT_NULL allocator,
    uint32_t allocationCount,
    const VmaAllocation VMA_NOT_NULL* VMA_NULLABLE VMA_LEN_IF_NOT_NULL(allocationCount) allocations,
    const VkDeviceSize* VMA_NULLABLE VMA_LEN_IF_NOT_NULL(allocationCount) offsets,
    const VkDeviceSize* VMA_NULLABLE VMA_LEN_IF_NOT_NULL(allocationCount) sizes);

/** \brief Checks magic number in margins around all allocations in given memory types (in both default and custom pools) in search for corruptions.

\param allocator
\param memoryTypeBits Bit mask, where each bit set means that a memory type with that index should be checked.

Corruption detection is enabled only when `VMA_DEBUG_DETECT_CORRUPTION` macro is defined to nonzero,
`VMA_DEBUG_MARGIN` is defined to nonzero and only for memory types that are
`HOST_VISIBLE` and `HOST_COHERENT`. For more information, see [Corruption detection](@ref debugging_memory_usage_corruption_detection).

Possible return values:

- `VK_ERROR_FEATURE_NOT_PRESENT` - corruption detection is not enabled for any of specified memory types.
- `VK_SUCCESS` - corruption detection has been performed and succeeded.
- `VK_ERROR_UNKNOWN` - corruption detection has been performed and found memory corruptions around one of the allocations.
  `VMA_ASSERT` is also fired in that case.
- Other value: Error returned by Vulkan, e.g. memory mapping failure.
*/
VMA_CALL_PRE VkResult VMA_CALL_POST vmaCheckCorruption(
    VmaAllocator VMA_NOT_NULL allocator,
    uint32_t memoryTypeBits);

/** \brief Begins defragmentation process.

\param allocator Allocator object.
\param pInfo Structure filled with parameters of defragmentation.
\param[out] pContext Context object that must be passed to vmaEndDefragmentation() to finish defragmentation.
\returns
- `VK_SUCCESS` if defragmentation can begin.
- `VK_ERROR_FEATURE_NOT_PRESENT` if defragmentation is not supported.

For more information about defragmentation, see documentation chapter:
[Defragmentation](@ref defragmentation).
*/
VMA_CALL_PRE VkResult VMA_CALL_POST vmaBeginDefragmentation(
    VmaAllocator VMA_NOT_NULL allocator,
    const VmaDefragmentationInfo* VMA_NOT_NULL pInfo,
    VmaDefragmentationContext VMA_NULLABLE* VMA_NOT_NULL pContext);

/** \brief Ends defragmentation process.

\param allocator Allocator object.
\param context Context object that has been created by vmaBeginDefragmentation().
\param[out] pStats Optional stats for the defragmentation. Can be null.

Use this function to finish defragmentation started by vmaBeginDefragmentation().
*/
VMA_CALL_PRE void VMA_CALL_POST vmaEndDefragmentation(
    VmaAllocator VMA_NOT_NULL allocator,
    VmaDefragmentationContext VMA_NOT_NULL context,
    VmaDefragmentationStats* VMA_NULLABLE pStats);

/** \brief Starts single defragmentation pass.

\param allocator Allocator object.
\param context Context object that has been created by vmaBeginDefragmentation().
\param[out] pPassInfo Computed informations for current pass.
\returns
- `VK_SUCCESS` if no more moves are possible. Then you can omit call to vmaEndDefragmentationPass() and simply end whole defragmentation.
- `VK_INCOMPLETE` if there are pending moves returned in `pPassInfo`. You need to perform them, call vmaEndDefragmentationPass(),
  and then preferably try another pass with vmaBeginDefragmentationPass().
*/
VMA_CALL_PRE VkResult VMA_CALL_POST vmaBeginDefragmentationPass(
    VmaAllocator VMA_NOT_NULL allocator,
    VmaDefragmentationContext VMA_NOT_NULL context,
    VmaDefragmentationPassMoveInfo* VMA_NOT_NULL pPassInfo);

/** \brief Ends single defragmentation pass.

\param allocator Allocator object.
\param context Context object that has been created by vmaBeginDefragmentation().
\param pPassInfo Computed informations for current pass filled by vmaBeginDefragmentationPass() and possibly modified by you.

Returns `VK_SUCCESS` if no more moves are possible or `VK_INCOMPLETE` if more defragmentations are possible.

Ends incremental defragmentation pass and commits all defragmentation moves from `pPassInfo`.
After this call:

- Allocations at `pPassInfo[i].srcAllocation` that had `pPassInfo[i].operation ==` #VMA_DEFRAGMENTATION_MOVE_OPERATION_COPY
  (which is the default) will be pointing to the new destination place.
- Allocation at `pPassInfo[i].srcAllocation` that had `pPassInfo[i].operation ==` #VMA_DEFRAGMENTATION_MOVE_OPERATION_DESTROY
  will be freed.

If no more moves are possible you can end whole defragmentation.
*/
VMA_CALL_PRE VkResult VMA_CALL_POST vmaEndDefragmentationPass(
    VmaAllocator VMA_NOT_NULL allocator,
    VmaDefragmentationContext VMA_NOT_NULL context,
    VmaDefragmentationPassMoveInfo* VMA_NOT_NULL pPassInfo);

/** \brief Binds buffer to allocation.

Binds specified buffer to region of memory represented by specified allocation.
Gets `VkDeviceMemory` handle and offset from the allocation.
If you want to create a buffer, allocate memory for it and bind them together separately,
you should use this function for binding instead of standard `vkBindBufferMemory()`,
because it ensures proper synchronization so that when a `VkDeviceMemory` object is used by multiple
allocations, calls to `vkBind*Memory()` or `vkMapMemory()` won't happen from multiple threads simultaneously
(which is illegal in Vulkan).

It is recommended to use function vmaCreateBuffer() instead of this one.
*/
VMA_CALL_PRE VkResult VMA_CALL_POST vmaBindBufferMemory(
    VmaAllocator VMA_NOT_NULL allocator,
    VmaAllocation VMA_NOT_NULL allocation,
    VkBuffer VMA_NOT_NULL_NON_DISPATCHABLE buffer);

/** \brief Binds buffer to allocation with additional parameters.

\param allocator
\param allocation
\param allocationLocalOffset Additional offset to be added while binding, relative to the beginning of the `allocation`. Normally it should be 0.
\param buffer
\param pNext A chain of structures to be attached to `VkBindBufferMemoryInfoKHR` structure used internally. Normally it should be null.

This function is similar to vmaBindBufferMemory(), but it provides additional parameters.

If `pNext` is not null, #VmaAllocator object must have been created with #VMA_ALLOCATOR_CREATE_KHR_BIND_MEMORY2_BIT flag
or with VmaAllocatorCreateInfo::vulkanApiVersion `>= VK_API_VERSION_1_1`. Otherwise the call fails.
*/
VMA_CALL_PRE VkResult VMA_CALL_POST vmaBindBufferMemory2(
    VmaAllocator VMA_NOT_NULL allocator,
    VmaAllocation VMA_NOT_NULL allocation,
    VkDeviceSize allocationLocalOffset,
    VkBuffer VMA_NOT_NULL_NON_DISPATCHABLE buffer,
    const void* VMA_NULLABLE pNext);

/** \brief Binds image to allocation.

Binds specified image to region of memory represented by specified allocation.
Gets `VkDeviceMemory` handle and offset from the allocation.
If you want to create an image, allocate memory for it and bind them together separately,
you should use this function for binding instead of standard `vkBindImageMemory()`,
because it ensures proper synchronization so that when a `VkDeviceMemory` object is used by multiple
allocations, calls to `vkBind*Memory()` or `vkMapMemory()` won't happen from multiple threads simultaneously
(which is illegal in Vulkan).

It is recommended to use function vmaCreateImage() instead of this one.
*/
VMA_CALL_PRE VkResult VMA_CALL_POST vmaBindImageMemory(
    VmaAllocator VMA_NOT_NULL allocator,
    VmaAllocation VMA_NOT_NULL allocation,
    VkImage VMA_NOT_NULL_NON_DISPATCHABLE image);

/** \brief Binds image to allocation with additional parameters.

\param allocator
\param allocation
\param allocationLocalOffset Additional offset to be added while binding, relative to the beginning of the `allocation`. Normally it should be 0.
\param image
\param pNext A chain of structures to be attached to `VkBindImageMemoryInfoKHR` structure used internally. Normally it should be null.

This function is similar to vmaBindImageMemory(), but it provides additional parameters.

If `pNext` is not null, #VmaAllocator object must have been created with #VMA_ALLOCATOR_CREATE_KHR_BIND_MEMORY2_BIT flag
or with VmaAllocatorCreateInfo::vulkanApiVersion `>= VK_API_VERSION_1_1`. Otherwise the call fails.
*/
VMA_CALL_PRE VkResult VMA_CALL_POST vmaBindImageMemory2(
    VmaAllocator VMA_NOT_NULL allocator,
    VmaAllocation VMA_NOT_NULL allocation,
    VkDeviceSize allocationLocalOffset,
    VkImage VMA_NOT_NULL_NON_DISPATCHABLE image,
    const void* VMA_NULLABLE pNext);

/** \brief Creates a new `VkBuffer`, allocates and binds memory for it.

\param allocator
\param pBufferCreateInfo
\param pAllocationCreateInfo
\param[out] pBuffer Buffer that was created.
\param[out] pAllocation Allocation that was created.
\param[out] pAllocationInfo Optional. Information about allocated memory. It can be later fetched using function vmaGetAllocationInfo().

This function automatically:

-# Creates buffer.
-# Allocates appropriate memory for it.
-# Binds the buffer with the memory.

If any of these operations fail, buffer and allocation are not created,
returned value is negative error code, `*pBuffer` and `*pAllocation` are null.

If the function succeeded, you must destroy both buffer and allocation when you
no longer need them using either convenience function vmaDestroyBuffer() or
separately, using `vkDestroyBuffer()` and vmaFreeMemory().

If #VMA_ALLOCATOR_CREATE_KHR_DEDICATED_ALLOCATION_BIT flag was used,
VK_KHR_dedicated_allocation extension is used internally to query driver whether
it requires or prefers the new buffer to have dedicated allocation. If yes,
and if dedicated allocation is possible
(#VMA_ALLOCATION_CREATE_NEVER_ALLOCATE_BIT is not used), it creates dedicated
allocation for this buffer, just like when using
#VMA_ALLOCATION_CREATE_DEDICATED_MEMORY_BIT.

\note This function creates a new `VkBuffer`. Sub-allocation of parts of one large buffer,
although recommended as a good practice, is out of scope of this library and could be implemented
by the user as a higher-level logic on top of VMA.
*/
VMA_CALL_PRE VkResult VMA_CALL_POST vmaCreateBuffer(
    VmaAllocator VMA_NOT_NULL allocator,
    const VkBufferCreateInfo* VMA_NOT_NULL pBufferCreateInfo,
    const VmaAllocationCreateInfo* VMA_NOT_NULL pAllocationCreateInfo,
    VkBuffer VMA_NULLABLE_NON_DISPATCHABLE* VMA_NOT_NULL pBuffer,
    VmaAllocation VMA_NULLABLE* VMA_NOT_NULL pAllocation,
    VmaAllocationInfo* VMA_NULLABLE pAllocationInfo);

/** \brief Creates a buffer with additional minimum alignment.

Similar to vmaCreateBuffer() but provides additional parameter `minAlignment` which allows to specify custom,
minimum alignment to be used when placing the buffer inside a larger memory block, which may be needed e.g.
for interop with OpenGL.
*/
VMA_CALL_PRE VkResult VMA_CALL_POST vmaCreateBufferWithAlignment(
    VmaAllocator VMA_NOT_NULL allocator,
    const VkBufferCreateInfo* VMA_NOT_NULL pBufferCreateInfo,
    const VmaAllocationCreateInfo* VMA_NOT_NULL pAllocationCreateInfo,
    VkDeviceSize minAlignment,
    VkBuffer VMA_NULLABLE_NON_DISPATCHABLE* VMA_NOT_NULL pBuffer,
    VmaAllocation VMA_NULLABLE* VMA_NOT_NULL pAllocation,
    VmaAllocationInfo* VMA_NULLABLE pAllocationInfo);

/** \brief Creates a new `VkBuffer`, binds already created memory for it.

\param allocator
\param allocation Allocation that provides memory to be used for binding new buffer to it.
\param pBufferCreateInfo
\param[out] pBuffer Buffer that was created.

This function automatically:

-# Creates buffer.
-# Binds the buffer with the supplied memory.

If any of these operations fail, buffer is not created,
returned value is negative error code and `*pBuffer` is null.

If the function succeeded, you must destroy the buffer when you
no longer need it using `vkDestroyBuffer()`. If you want to also destroy the corresponding
allocation you can use convenience function vmaDestroyBuffer().
*/
VMA_CALL_PRE VkResult VMA_CALL_POST vmaCreateAliasingBuffer(
    VmaAllocator VMA_NOT_NULL allocator,
    VmaAllocation VMA_NOT_NULL allocation,
    const VkBufferCreateInfo* VMA_NOT_NULL pBufferCreateInfo,
    VkBuffer VMA_NULLABLE_NON_DISPATCHABLE* VMA_NOT_NULL pBuffer);

/** \brief Destroys Vulkan buffer and frees allocated memory.

This is just a convenience function equivalent to:

\code
vkDestroyBuffer(device, buffer, allocationCallbacks);
vmaFreeMemory(allocator, allocation);
\endcode

It it safe to pass null as buffer and/or allocation.
*/
VMA_CALL_PRE void VMA_CALL_POST vmaDestroyBuffer(
    VmaAllocator VMA_NOT_NULL allocator,
    VkBuffer VMA_NULLABLE_NON_DISPATCHABLE buffer,
    VmaAllocation VMA_NULLABLE allocation);

/// Function similar to vmaCreateBuffer().
VMA_CALL_PRE VkResult VMA_CALL_POST vmaCreateImage(
    VmaAllocator VMA_NOT_NULL allocator,
    const VkImageCreateInfo* VMA_NOT_NULL pImageCreateInfo,
    const VmaAllocationCreateInfo* VMA_NOT_NULL pAllocationCreateInfo,
    VkImage VMA_NULLABLE_NON_DISPATCHABLE* VMA_NOT_NULL pImage,
    VmaAllocation VMA_NULLABLE* VMA_NOT_NULL pAllocation,
    VmaAllocationInfo* VMA_NULLABLE pAllocationInfo);

/// Function similar to vmaCreateAliasingBuffer().
VMA_CALL_PRE VkResult VMA_CALL_POST vmaCreateAliasingImage(
    VmaAllocator VMA_NOT_NULL allocator,
    VmaAllocation VMA_NOT_NULL allocation,
    const VkImageCreateInfo* VMA_NOT_NULL pImageCreateInfo,
    VkImage VMA_NULLABLE_NON_DISPATCHABLE* VMA_NOT_NULL pImage);

/** \brief Destroys Vulkan image and frees allocated memory.

This is just a convenience function equivalent to:

\code
vkDestroyImage(device, image, allocationCallbacks);
vmaFreeMemory(allocator, allocation);
\endcode

It it safe to pass null as image and/or allocation.
*/
VMA_CALL_PRE void VMA_CALL_POST vmaDestroyImage(
    VmaAllocator VMA_NOT_NULL allocator,
    VkImage VMA_NULLABLE_NON_DISPATCHABLE image,
    VmaAllocation VMA_NULLABLE allocation);

/** @} */

/**
\addtogroup group_virtual
@{
*/

/** \brief Creates new #VmaVirtualBlock object.

\param pCreateInfo Parameters for creation.
\param[out] pVirtualBlock Returned virtual block object or `VMA_NULL` if creation failed.
*/
VMA_CALL_PRE VkResult VMA_CALL_POST vmaCreateVirtualBlock(
    const VmaVirtualBlockCreateInfo* VMA_NOT_NULL pCreateInfo,
    VmaVirtualBlock VMA_NULLABLE* VMA_NOT_NULL pVirtualBlock);

/** \brief Destroys #VmaVirtualBlock object.

Please note that you should consciously handle virtual allocations that could remain unfreed in the block.
You should either free them individually using vmaVirtualFree() or call vmaClearVirtualBlock()
if you are sure this is what you want. If you do neither, an assert is called.

If you keep pointers to some additional metadata associated with your virtual allocations in their `pUserData`,
don't forget to free them.
*/
VMA_CALL_PRE void VMA_CALL_POST vmaDestroyVirtualBlock(
    VmaVirtualBlock VMA_NULLABLE virtualBlock);

/** \brief Returns true of the #VmaVirtualBlock is empty - contains 0 virtual allocations and has all its space available for new allocations.
*/
VMA_CALL_PRE VkBool32 VMA_CALL_POST vmaIsVirtualBlockEmpty(
    VmaVirtualBlock VMA_NOT_NULL virtualBlock);

/** \brief Returns information about a specific virtual allocation within a virtual block, like its size and `pUserData` pointer.
*/
VMA_CALL_PRE void VMA_CALL_POST vmaGetVirtualAllocationInfo(
    VmaVirtualBlock VMA_NOT_NULL virtualBlock,
    VmaVirtualAllocation VMA_NOT_NULL_NON_DISPATCHABLE allocation, VmaVirtualAllocationInfo* VMA_NOT_NULL pVirtualAllocInfo);

/** \brief Allocates new virtual allocation inside given #VmaVirtualBlock.

If the allocation fails due to not enough free space available, `VK_ERROR_OUT_OF_DEVICE_MEMORY` is returned
(despite the function doesn't ever allocate actual GPU memory).
`pAllocation` is then set to `VK_NULL_HANDLE` and `pOffset`, if not null, it set to `UINT64_MAX`.

\param virtualBlock Virtual block
\param pCreateInfo Parameters for the allocation
\param[out] pAllocation Returned handle of the new allocation
\param[out] pOffset Returned offset of the new allocation. Optional, can be null.
*/
VMA_CALL_PRE VkResult VMA_CALL_POST vmaVirtualAllocate(
    VmaVirtualBlock VMA_NOT_NULL virtualBlock,
    const VmaVirtualAllocationCreateInfo* VMA_NOT_NULL pCreateInfo,
    VmaVirtualAllocation VMA_NULLABLE_NON_DISPATCHABLE* VMA_NOT_NULL pAllocation,
    VkDeviceSize* VMA_NULLABLE pOffset);

/** \brief Frees virtual allocation inside given #VmaVirtualBlock.

It is correct to call this function with `allocation == VK_NULL_HANDLE` - it does nothing.
*/
VMA_CALL_PRE void VMA_CALL_POST vmaVirtualFree(
    VmaVirtualBlock VMA_NOT_NULL virtualBlock,
    VmaVirtualAllocation VMA_NULLABLE_NON_DISPATCHABLE allocation);

/** \brief Frees all virtual allocations inside given #VmaVirtualBlock.

You must either call this function or free each virtual allocation individually with vmaVirtualFree()
before destroying a virtual block. Otherwise, an assert is called.

If you keep pointer to some additional metadata associated with your virtual allocation in its `pUserData`,
don't forget to free it as well.
*/
VMA_CALL_PRE void VMA_CALL_POST vmaClearVirtualBlock(
    VmaVirtualBlock VMA_NOT_NULL virtualBlock);

/** \brief Changes custom pointer associated with given virtual allocation.
*/
VMA_CALL_PRE void VMA_CALL_POST vmaSetVirtualAllocationUserData(
    VmaVirtualBlock VMA_NOT_NULL virtualBlock,
    VmaVirtualAllocation VMA_NOT_NULL_NON_DISPATCHABLE allocation,
    void* VMA_NULLABLE pUserData);

/** \brief Calculates and returns statistics about virtual allocations and memory usage in given #VmaVirtualBlock.

This function is fast to call. For more detailed statistics, see vmaCalculateVirtualBlockStatistics().
*/
VMA_CALL_PRE void VMA_CALL_POST vmaGetVirtualBlockStatistics(
    VmaVirtualBlock VMA_NOT_NULL virtualBlock,
    VmaStatistics* VMA_NOT_NULL pStats);

/** \brief Calculates and returns detailed statistics about virtual allocations and memory usage in given #VmaVirtualBlock.

This function is slow to call. Use for debugging purposes.
For less detailed statistics, see vmaGetVirtualBlockStatistics().
*/
VMA_CALL_PRE void VMA_CALL_POST vmaCalculateVirtualBlockStatistics(
    VmaVirtualBlock VMA_NOT_NULL virtualBlock,
    VmaDetailedStatistics* VMA_NOT_NULL pStats);

/** @} */

#if VMA_STATS_STRING_ENABLED
/**
\addtogroup group_stats
@{
*/

/** \brief Builds and returns a null-terminated string in JSON format with information about given #VmaVirtualBlock.
\param virtualBlock Virtual block.
\param[out] ppStatsString Returned string.
\param detailedMap Pass `VK_FALSE` to only obtain statistics as returned by vmaCalculateVirtualBlockStatistics(). Pass `VK_TRUE` to also obtain full list of allocations and free spaces.

Returned string must be freed using vmaFreeVirtualBlockStatsString().
*/
VMA_CALL_PRE void VMA_CALL_POST vmaBuildVirtualBlockStatsString(
    VmaVirtualBlock VMA_NOT_NULL virtualBlock,
    char* VMA_NULLABLE* VMA_NOT_NULL ppStatsString,
    VkBool32 detailedMap);

/// Frees a string returned by vmaBuildVirtualBlockStatsString().
VMA_CALL_PRE void VMA_CALL_POST vmaFreeVirtualBlockStatsString(
    VmaVirtualBlock VMA_NOT_NULL virtualBlock,
    char* VMA_NULLABLE pStatsString);

/** \brief Builds and returns statistics as a null-terminated string in JSON format.
\param allocator
\param[out] ppStatsString Must be freed using vmaFreeStatsString() function.
\param detailedMap
*/
VMA_CALL_PRE void VMA_CALL_POST vmaBuildStatsString(
    VmaAllocator VMA_NOT_NULL allocator,
    char* VMA_NULLABLE* VMA_NOT_NULL ppStatsString,
    VkBool32 detailedMap);

VMA_CALL_PRE void VMA_CALL_POST vmaFreeStatsString(
    VmaAllocator VMA_NOT_NULL allocator,
    char* VMA_NULLABLE pStatsString);

/** @} */

#endif // VMA_STATS_STRING_ENABLED

#endif // _VMA_FUNCTION_HEADERS

#ifdef __cplusplus
}
#endif

#endif // AMD_VULKAN_MEMORY_ALLOCATOR_H

////////////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////
// 
//    IMPLEMENTATION
// 
////////////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////

// For Visual Studio IntelliSense.
#if defined(__cplusplus) && defined(__INTELLISENSE__)
#define VMA_IMPLEMENTATION
#endif

#ifdef VMA_IMPLEMENTATION
#undef VMA_IMPLEMENTATION

#include <cstdint>
#include <cstdlib>
#include <cstring>
#include <utility>
#include <type_traits>

#ifdef _MSC_VER
    #include <intrin.h> // For functions like __popcnt, _BitScanForward etc.
#endif
#if __cplusplus >= 202002L || _MSVC_LANG >= 202002L // C++20
    #include <bit> // For std::popcount
#endif

/*******************************************************************************
CONFIGURATION SECTION

Define some of these macros before each #include of this header or change them
here if you need other then default behavior depending on your environment.
*/
#ifndef _VMA_CONFIGURATION

/*
Define this macro to 1 to make the library fetch pointers to Vulkan functions
internally, like:

    vulkanFunctions.vkAllocateMemory = &vkAllocateMemory;
*/
#if !defined(VMA_STATIC_VULKAN_FUNCTIONS) && !defined(VK_NO_PROTOTYPES)
    #define VMA_STATIC_VULKAN_FUNCTIONS 1
#endif

/*
Define this macro to 1 to make the library fetch pointers to Vulkan functions
internally, like:

    vulkanFunctions.vkAllocateMemory = (PFN_vkAllocateMemory)vkGetDeviceProcAddr(device, "vkAllocateMemory");

To use this feature in new versions of VMA you now have to pass
VmaVulkanFunctions::vkGetInstanceProcAddr and vkGetDeviceProcAddr as
VmaAllocatorCreateInfo::pVulkanFunctions. Other members can be null.
*/
#if !defined(VMA_DYNAMIC_VULKAN_FUNCTIONS)
    #define VMA_DYNAMIC_VULKAN_FUNCTIONS 1
#endif

#ifndef VMA_USE_STL_SHARED_MUTEX
    // Compiler conforms to C++17.
    #if __cplusplus >= 201703L
        #define VMA_USE_STL_SHARED_MUTEX 1
    // Visual studio defines __cplusplus properly only when passed additional parameter: /Zc:__cplusplus
    // Otherwise it is always 199711L, despite shared_mutex works since Visual Studio 2015 Update 2.
    #elif defined(_MSC_FULL_VER) && _MSC_FULL_VER >= 190023918 && __cplusplus == 199711L && _MSVC_LANG >= 201703L
        #define VMA_USE_STL_SHARED_MUTEX 1
    #else
        #define VMA_USE_STL_SHARED_MUTEX 0
    #endif
#endif

/*
Define this macro to include custom header files without having to edit this file directly, e.g.:

    // Inside of "my_vma_configuration_user_includes.h":

    #include "my_custom_assert.h" // for MY_CUSTOM_ASSERT
    #include "my_custom_min.h" // for my_custom_min
    #include <algorithm>
    #include <mutex>

    // Inside a different file, which includes "vk_mem_alloc.h":

    #define VMA_CONFIGURATION_USER_INCLUDES_H "my_vma_configuration_user_includes.h"
    #define VMA_ASSERT(expr) MY_CUSTOM_ASSERT(expr)
    #define VMA_MIN(v1, v2)  (my_custom_min(v1, v2))
    #include "vk_mem_alloc.h"
    ...

The following headers are used in this CONFIGURATION section only, so feel free to
remove them if not needed.
*/
#if !defined(VMA_CONFIGURATION_USER_INCLUDES_H)
    #include <cassert> // for assert
    #include <algorithm> // for min, max
    #include <mutex>
#else
    #include VMA_CONFIGURATION_USER_INCLUDES_H
#endif

#ifndef VMA_NULL
   // Value used as null pointer. Define it to e.g.: nullptr, NULL, 0, (void*)0.
   #define VMA_NULL   nullptr
#endif

#if defined(__ANDROID_API__) && (__ANDROID_API__ < 16)
#include <cstdlib>
static void* vma_aligned_alloc(size_t alignment, size_t size)
{
    // alignment must be >= sizeof(void*)
    if(alignment < sizeof(void*))
    {
        alignment = sizeof(void*);
    }

    return memalign(alignment, size);
}
#elif defined(__APPLE__) || defined(__ANDROID__) || (defined(__linux__) && defined(__GLIBCXX__) && !defined(_GLIBCXX_HAVE_ALIGNED_ALLOC))
#include <cstdlib>

#if defined(__APPLE__)
#include <AvailabilityMacros.h>
#endif

static void* vma_aligned_alloc(size_t alignment, size_t size)
{
    // Unfortunately, aligned_alloc causes VMA to crash due to it returning null pointers. (At least under 11.4)
    // Therefore, for now disable this specific exception until a proper solution is found.
    //#if defined(__APPLE__) && (defined(MAC_OS_X_VERSION_10_16) || defined(__IPHONE_14_0))
    //#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_16 || __IPHONE_OS_VERSION_MAX_ALLOWED >= __IPHONE_14_0
    //    // For C++14, usr/include/malloc/_malloc.h declares aligned_alloc()) only
    //    // with the MacOSX11.0 SDK in Xcode 12 (which is what adds
    //    // MAC_OS_X_VERSION_10_16), even though the function is marked
    //    // availabe for 10.15. That is why the preprocessor checks for 10.16 but
    //    // the __builtin_available checks for 10.15.
    //    // People who use C++17 could call aligned_alloc with the 10.15 SDK already.
    //    if (__builtin_available(macOS 10.15, iOS 13, *))
    //        return aligned_alloc(alignment, size);
    //#endif
    //#endif

    // alignment must be >= sizeof(void*)
    if(alignment < sizeof(void*))
    {
        alignment = sizeof(void*);
    }

    void *pointer;
    if(posix_memalign(&pointer, alignment, size) == 0)
        return pointer;
    return VMA_NULL;
}
#elif defined(_WIN32)
static void* vma_aligned_alloc(size_t alignment, size_t size)
{
    return _aligned_malloc(size, alignment);
}
#else
static void* vma_aligned_alloc(size_t alignment, size_t size)
{
    return aligned_alloc(alignment, size);
}
#endif

#if defined(_WIN32)
static void vma_aligned_free(void* ptr)
{
    _aligned_free(ptr);
}
#else
static void vma_aligned_free(void* VMA_NULLABLE ptr)
{
    free(ptr);
}
#endif

// If your compiler is not compatible with C++11 and definition of
// aligned_alloc() function is missing, uncommeting following line may help:

//#include <malloc.h>

// Normal assert to check for programmer's errors, especially in Debug configuration.
#ifndef VMA_ASSERT
   #ifdef NDEBUG
       #define VMA_ASSERT(expr)
   #else
       #define VMA_ASSERT(expr)         assert(expr)
   #endif
#endif

// Assert that will be called very often, like inside data structures e.g. operator[].
// Making it non-empty can make program slow.
#ifndef VMA_HEAVY_ASSERT
   #ifdef NDEBUG
       #define VMA_HEAVY_ASSERT(expr)
   #else
       #define VMA_HEAVY_ASSERT(expr)   //VMA_ASSERT(expr)
   #endif
#endif

#ifndef VMA_ALIGN_OF
   #define VMA_ALIGN_OF(type)       (__alignof(type))
#endif

#ifndef VMA_SYSTEM_ALIGNED_MALLOC
   #define VMA_SYSTEM_ALIGNED_MALLOC(size, alignment) vma_aligned_alloc((alignment), (size))
#endif

#ifndef VMA_SYSTEM_ALIGNED_FREE
   // VMA_SYSTEM_FREE is the old name, but might have been defined by the user
   #if defined(VMA_SYSTEM_FREE)
      #define VMA_SYSTEM_ALIGNED_FREE(ptr)     VMA_SYSTEM_FREE(ptr)
   #else
      #define VMA_SYSTEM_ALIGNED_FREE(ptr)     vma_aligned_free(ptr)
    #endif
#endif

#ifndef VMA_COUNT_BITS_SET
    // Returns number of bits set to 1 in (v)
    #define VMA_COUNT_BITS_SET(v) VmaCountBitsSet(v)
#endif

#ifndef VMA_BITSCAN_LSB
    // Scans integer for index of first nonzero value from the Least Significant Bit (LSB). If mask is 0 then returns UINT8_MAX
    #define VMA_BITSCAN_LSB(mask) VmaBitScanLSB(mask)
#endif

#ifndef VMA_BITSCAN_MSB
    // Scans integer for index of first nonzero value from the Most Significant Bit (MSB). If mask is 0 then returns UINT8_MAX
    #define VMA_BITSCAN_MSB(mask) VmaBitScanMSB(mask)
#endif

#ifndef VMA_MIN
   #define VMA_MIN(v1, v2)    ((std::min)((v1), (v2)))
#endif

#ifndef VMA_MAX
   #define VMA_MAX(v1, v2)    ((std::max)((v1), (v2)))
#endif

#ifndef VMA_SWAP
   #define VMA_SWAP(v1, v2)   std::swap((v1), (v2))
#endif

#ifndef VMA_SORT
   #define VMA_SORT(beg, end, cmp)  std::sort(beg, end, cmp)
#endif

#ifndef VMA_DEBUG_LOG
   #define VMA_DEBUG_LOG(format, ...)
   /*
   #define VMA_DEBUG_LOG(format, ...) do { \
       printf(format, __VA_ARGS__); \
       printf("\n"); \
   } while(false)
   */
#endif

// Define this macro to 1 to enable functions: vmaBuildStatsString, vmaFreeStatsString.
#if VMA_STATS_STRING_ENABLED
    static inline void VmaUint32ToStr(char* VMA_NOT_NULL outStr, size_t strLen, uint32_t num)
    {
        snprintf(outStr, strLen, "%u", static_cast<unsigned int>(num));
    }
    static inline void VmaUint64ToStr(char* VMA_NOT_NULL outStr, size_t strLen, uint64_t num)
    {
        snprintf(outStr, strLen, "%llu", static_cast<unsigned long long>(num));
    }
    static inline void VmaPtrToStr(char* VMA_NOT_NULL outStr, size_t strLen, const void* ptr)
    {
        snprintf(outStr, strLen, "%p", ptr);
    }
#endif

#ifndef VMA_MUTEX
    class VmaMutex
    {
    public:
        void Lock() { m_Mutex.lock(); }
        void Unlock() { m_Mutex.unlock(); }
        bool TryLock() { return m_Mutex.try_lock(); }
    private:
        std::mutex m_Mutex;
    };
    #define VMA_MUTEX VmaMutex
#endif

// Read-write mutex, where "read" is shared access, "write" is exclusive access.
#ifndef VMA_RW_MUTEX
    #if VMA_USE_STL_SHARED_MUTEX
        // Use std::shared_mutex from C++17.
        #include <shared_mutex>
        class VmaRWMutex
        {
        public:
            void LockRead() { m_Mutex.lock_shared(); }
            void UnlockRead() { m_Mutex.unlock_shared(); }
            bool TryLockRead() { return m_Mutex.try_lock_shared(); }
            void LockWrite() { m_Mutex.lock(); }
            void UnlockWrite() { m_Mutex.unlock(); }
            bool TryLockWrite() { return m_Mutex.try_lock(); }
        private:
            std::shared_mutex m_Mutex;
        };
        #define VMA_RW_MUTEX VmaRWMutex
    #elif defined(_WIN32) && defined(WINVER) && WINVER >= 0x0600
        // Use SRWLOCK from WinAPI.
        // Minimum supported client = Windows Vista, server = Windows Server 2008.
        class VmaRWMutex
        {
        public:
            VmaRWMutex() { InitializeSRWLock(&m_Lock); }
            void LockRead() { AcquireSRWLockShared(&m_Lock); }
            void UnlockRead() { ReleaseSRWLockShared(&m_Lock); }
            bool TryLockRead() { return TryAcquireSRWLockShared(&m_Lock) != FALSE; }
            void LockWrite() { AcquireSRWLockExclusive(&m_Lock); }
            void UnlockWrite() { ReleaseSRWLockExclusive(&m_Lock); }
            bool TryLockWrite() { return TryAcquireSRWLockExclusive(&m_Lock) != FALSE; }
        private:
            SRWLOCK m_Lock;
        };
        #define VMA_RW_MUTEX VmaRWMutex
    #else
        // Less efficient fallback: Use normal mutex.
        class VmaRWMutex
        {
        public:
            void LockRead() { m_Mutex.Lock(); }
            void UnlockRead() { m_Mutex.Unlock(); }
            bool TryLockRead() { return m_Mutex.TryLock(); }
            void LockWrite() { m_Mutex.Lock(); }
            void UnlockWrite() { m_Mutex.Unlock(); }
            bool TryLockWrite() { return m_Mutex.TryLock(); }
        private:
            VMA_MUTEX m_Mutex;
        };
        #define VMA_RW_MUTEX VmaRWMutex
    #endif // #if VMA_USE_STL_SHARED_MUTEX
#endif // #ifndef VMA_RW_MUTEX

/*
If providing your own implementation, you need to implement a subset of std::atomic.
*/
#ifndef VMA_ATOMIC_UINT32
    #include <atomic>
    #define VMA_ATOMIC_UINT32 std::atomic<uint32_t>
#endif

#ifndef VMA_ATOMIC_UINT64
    #include <atomic>
    #define VMA_ATOMIC_UINT64 std::atomic<uint64_t>
#endif

#ifndef VMA_DEBUG_ALWAYS_DEDICATED_MEMORY
    /**
    Every allocation will have its own memory block.
    Define to 1 for debugging purposes only.
    */
    #define VMA_DEBUG_ALWAYS_DEDICATED_MEMORY (0)
#endif

#ifndef VMA_MIN_ALIGNMENT
    /**
    Minimum alignment of all allocations, in bytes.
    Set to more than 1 for debugging purposes. Must be power of two.
    */
    #ifdef VMA_DEBUG_ALIGNMENT // Old name
        #define VMA_MIN_ALIGNMENT VMA_DEBUG_ALIGNMENT
    #else
        #define VMA_MIN_ALIGNMENT (1)
    #endif
#endif

#ifndef VMA_DEBUG_MARGIN
    /**
    Minimum margin after every allocation, in bytes.
    Set nonzero for debugging purposes only.
    */
    #define VMA_DEBUG_MARGIN (0)
#endif

#ifndef VMA_DEBUG_INITIALIZE_ALLOCATIONS
    /**
    Define this macro to 1 to automatically fill new allocations and destroyed
    allocations with some bit pattern.
    */
    #define VMA_DEBUG_INITIALIZE_ALLOCATIONS (0)
#endif

#ifndef VMA_DEBUG_DETECT_CORRUPTION
    /**
    Define this macro to 1 together with non-zero value of VMA_DEBUG_MARGIN to
    enable writing magic value to the margin after every allocation and
    validating it, so that memory corruptions (out-of-bounds writes) are detected.
    */
    #define VMA_DEBUG_DETECT_CORRUPTION (0)
#endif

#ifndef VMA_DEBUG_GLOBAL_MUTEX
    /**
    Set this to 1 for debugging purposes only, to enable single mutex protecting all
    entry calls to the library. Can be useful for debugging multithreading issues.
    */
    #define VMA_DEBUG_GLOBAL_MUTEX (0)
#endif

#ifndef VMA_DEBUG_MIN_BUFFER_IMAGE_GRANULARITY
    /**
    Minimum value for VkPhysicalDeviceLimits::bufferImageGranularity.
    Set to more than 1 for debugging purposes only. Must be power of two.
    */
    #define VMA_DEBUG_MIN_BUFFER_IMAGE_GRANULARITY (1)
#endif

#ifndef VMA_DEBUG_DONT_EXCEED_MAX_MEMORY_ALLOCATION_COUNT
    /*
    Set this to 1 to make VMA never exceed VkPhysicalDeviceLimits::maxMemoryAllocationCount
    and return error instead of leaving up to Vulkan implementation what to do in such cases.
    */
    #define VMA_DEBUG_DONT_EXCEED_MAX_MEMORY_ALLOCATION_COUNT (0)
#endif

#ifndef VMA_SMALL_HEAP_MAX_SIZE
   /// Maximum size of a memory heap in Vulkan to consider it "small".
   #define VMA_SMALL_HEAP_MAX_SIZE (1024ull * 1024 * 1024)
#endif

#ifndef VMA_DEFAULT_LARGE_HEAP_BLOCK_SIZE
   /// Default size of a block allocated as single VkDeviceMemory from a "large" heap.
   #define VMA_DEFAULT_LARGE_HEAP_BLOCK_SIZE (256ull * 1024 * 1024)
#endif

/*
Mapping hysteresis is a logic that launches when vmaMapMemory/vmaUnmapMemory is called
or a persistently mapped allocation is created and destroyed several times in a row.
It keeps additional +1 mapping of a device memory block to prevent calling actual
vkMapMemory/vkUnmapMemory too many times, which may improve performance and help
tools like RenderDOc.
*/
#ifndef VMA_MAPPING_HYSTERESIS_ENABLED
    #define VMA_MAPPING_HYSTERESIS_ENABLED 1
#endif

#ifndef VMA_CLASS_NO_COPY
    #define VMA_CLASS_NO_COPY(className) \
        private: \
            className(const className&) = delete; \
            className& operator=(const className&) = delete;
#endif

#define VMA_VALIDATE(cond) do { if(!(cond)) { \
        VMA_ASSERT(0 && "Validation failed: " #cond); \
        return false; \
    } } while(false)

/*******************************************************************************
END OF CONFIGURATION
*/
#endif // _VMA_CONFIGURATION


static const uint8_t VMA_ALLOCATION_FILL_PATTERN_CREATED = 0xDC;
static const uint8_t VMA_ALLOCATION_FILL_PATTERN_DESTROYED = 0xEF;
// Decimal 2139416166, float NaN, little-endian binary 66 E6 84 7F.
static const uint32_t VMA_CORRUPTION_DETECTION_MAGIC_VALUE = 0x7F84E666;

// Copy of some Vulkan definitions so we don't need to check their existence just to handle few constants.
static const uint32_t VK_MEMORY_PROPERTY_DEVICE_COHERENT_BIT_AMD_COPY = 0x00000040;
static const uint32_t VK_MEMORY_PROPERTY_DEVICE_UNCACHED_BIT_AMD_COPY = 0x00000080;
static const uint32_t VK_BUFFER_USAGE_SHADER_DEVICE_ADDRESS_BIT_COPY = 0x00020000;
static const uint32_t VK_IMAGE_CREATE_DISJOINT_BIT_COPY = 0x00000200;
static const int32_t VK_IMAGE_TILING_DRM_FORMAT_MODIFIER_EXT_COPY = 1000158000;
static const uint32_t VMA_ALLOCATION_INTERNAL_STRATEGY_MIN_OFFSET = 0x10000000u;
static const uint32_t VMA_ALLOCATION_TRY_COUNT = 32;
static const uint32_t VMA_VENDOR_ID_AMD = 4098;

// This one is tricky. Vulkan specification defines this code as available since
// Vulkan 1.0, but doesn't actually define it in Vulkan SDK earlier than 1.2.131.
// See pull request #207.
#define VK_ERROR_UNKNOWN_COPY ((VkResult)-13)


#if VMA_STATS_STRING_ENABLED
// Correspond to values of enum VmaSuballocationType.
static const char* VMA_SUBALLOCATION_TYPE_NAMES[] =
{
    "FREE",
    "UNKNOWN",
    "BUFFER",
    "IMAGE_UNKNOWN",
    "IMAGE_LINEAR",
    "IMAGE_OPTIMAL",
};
#endif

static VkAllocationCallbacks VmaEmptyAllocationCallbacks =
    { VMA_NULL, VMA_NULL, VMA_NULL, VMA_NULL, VMA_NULL, VMA_NULL };


#ifndef _VMA_ENUM_DECLARATIONS

enum VmaSuballocationType
{
    VMA_SUBALLOCATION_TYPE_FREE = 0,
    VMA_SUBALLOCATION_TYPE_UNKNOWN = 1,
    VMA_SUBALLOCATION_TYPE_BUFFER = 2,
    VMA_SUBALLOCATION_TYPE_IMAGE_UNKNOWN = 3,
    VMA_SUBALLOCATION_TYPE_IMAGE_LINEAR = 4,
    VMA_SUBALLOCATION_TYPE_IMAGE_OPTIMAL = 5,
    VMA_SUBALLOCATION_TYPE_MAX_ENUM = 0x7FFFFFFF
};

enum VMA_CACHE_OPERATION
{
    VMA_CACHE_FLUSH,
    VMA_CACHE_INVALIDATE
};

enum class VmaAllocationRequestType
{
    Normal,
    TLSF,
    // Used by "Linear" algorithm.
    UpperAddress,
    EndOf1st,
    EndOf2nd,
};

#endif // _VMA_ENUM_DECLARATIONS

#ifndef _VMA_FORWARD_DECLARATIONS
// Opaque handle used by allocation algorithms to identify single allocation in any conforming way.
VK_DEFINE_NON_DISPATCHABLE_HANDLE(VmaAllocHandle);

struct VmaMutexLock;
struct VmaMutexLockRead;
struct VmaMutexLockWrite;

template<typename T>
struct AtomicTransactionalIncrement;

template<typename T>
struct VmaStlAllocator;

template<typename T, typename AllocatorT>
class VmaVector;

template<typename T, typename AllocatorT, size_t N>
class VmaSmallVector;

template<typename T>
class VmaPoolAllocator;

template<typename T>
struct VmaListItem;

template<typename T>
class VmaRawList;

template<typename T, typename AllocatorT>
class VmaList;

template<typename ItemTypeTraits>
class VmaIntrusiveLinkedList;

// Unused in this version
#if 0
template<typename T1, typename T2>
struct VmaPair;
template<typename FirstT, typename SecondT>
struct VmaPairFirstLess;

template<typename KeyT, typename ValueT>
class VmaMap;
#endif

#if VMA_STATS_STRING_ENABLED
class VmaStringBuilder;
class VmaJsonWriter;
#endif

class VmaDeviceMemoryBlock;

struct VmaDedicatedAllocationListItemTraits;
class VmaDedicatedAllocationList;

struct VmaSuballocation;
struct VmaSuballocationOffsetLess;
struct VmaSuballocationOffsetGreater;
struct VmaSuballocationItemSizeLess;

typedef VmaList<VmaSuballocation, VmaStlAllocator<VmaSuballocation>> VmaSuballocationList;

struct VmaAllocationRequest;

class VmaBlockMetadata;
class VmaBlockMetadata_Linear;
class VmaBlockMetadata_TLSF;

class VmaBlockVector;

struct VmaPoolListItemTraits;

struct VmaCurrentBudgetData;

class VmaAllocationObjectAllocator;

#endif // _VMA_FORWARD_DECLARATIONS


#ifndef _VMA_FUNCTIONS

/*
Returns number of bits set to 1 in (v).

On specific platforms and compilers you can use instrinsics like:

Visual Studio:
    return __popcnt(v);
GCC, Clang:
    return static_cast<uint32_t>(__builtin_popcount(v));

Define macro VMA_COUNT_BITS_SET to provide your optimized implementation.
But you need to check in runtime whether user's CPU supports these, as some old processors don't.
*/
static inline uint32_t VmaCountBitsSet(uint32_t v)
{
#if __cplusplus >= 202002L || _MSVC_LANG >= 202002L // C++20
    return std::popcount(v);
#else
    uint32_t c = v - ((v >> 1) & 0x55555555);
    c = ((c >> 2) & 0x33333333) + (c & 0x33333333);
    c = ((c >> 4) + c) & 0x0F0F0F0F;
    c = ((c >> 8) + c) & 0x00FF00FF;
    c = ((c >> 16) + c) & 0x0000FFFF;
    return c;
#endif
}

static inline uint8_t VmaBitScanLSB(uint64_t mask)
{
#if defined(_MSC_VER) && defined(_WIN64)
    unsigned long pos;
    if (_BitScanForward64(&pos, mask))
        return static_cast<uint8_t>(pos);
    return UINT8_MAX;
#elif defined __GNUC__ || defined __clang__
    return static_cast<uint8_t>(__builtin_ffsll(mask)) - 1U;
#else
    uint8_t pos = 0;
    uint64_t bit = 1;
    do
    {
        if (mask & bit)
            return pos;
        bit <<= 1;
    } while (pos++ < 63);
    return UINT8_MAX;
#endif
}

static inline uint8_t VmaBitScanLSB(uint32_t mask)
{
#ifdef _MSC_VER
    unsigned long pos;
    if (_BitScanForward(&pos, mask))
        return static_cast<uint8_t>(pos);
    return UINT8_MAX;
#elif defined __GNUC__ || defined __clang__
    return static_cast<uint8_t>(__builtin_ffs(mask)) - 1U;
#else
    uint8_t pos = 0;
    uint32_t bit = 1;
    do
    {
        if (mask & bit)
            return pos;
        bit <<= 1;
    } while (pos++ < 31);
    return UINT8_MAX;
#endif
}

static inline uint8_t VmaBitScanMSB(uint64_t mask)
{
#if defined(_MSC_VER) && defined(_WIN64)
    unsigned long pos;
    if (_BitScanReverse64(&pos, mask))
        return static_cast<uint8_t>(pos);
#elif defined __GNUC__ || defined __clang__
    if (mask)
        return 63 - static_cast<uint8_t>(__builtin_clzll(mask));
#else
    uint8_t pos = 63;
    uint64_t bit = 1ULL << 63;
    do
    {
        if (mask & bit)
            return pos;
        bit >>= 1;
    } while (pos-- > 0);
#endif
    return UINT8_MAX;
}

static inline uint8_t VmaBitScanMSB(uint32_t mask)
{
#ifdef _MSC_VER
    unsigned long pos;
    if (_BitScanReverse(&pos, mask))
        return static_cast<uint8_t>(pos);
#elif defined __GNUC__ || defined __clang__
    if (mask)
        return 31 - static_cast<uint8_t>(__builtin_clz(mask));
#else
    uint8_t pos = 31;
    uint32_t bit = 1UL << 31;
    do
    {
        if (mask & bit)
            return pos;
        bit >>= 1;
    } while (pos-- > 0);
#endif
    return UINT8_MAX;
}

/*
Returns true if given number is a power of two.
T must be unsigned integer number or signed integer but always nonnegative.
For 0 returns true.
*/
template <typename T>
inline bool VmaIsPow2(T x)
{
    return (x & (x - 1)) == 0;
}

// Aligns given value up to nearest multiply of align value. For example: VmaAlignUp(11, 8) = 16.
// Use types like uint32_t, uint64_t as T.
template <typename T>
static inline T VmaAlignUp(T val, T alignment)
{
    VMA_HEAVY_ASSERT(VmaIsPow2(alignment));
    return (val + alignment - 1) & ~(alignment - 1);
}

// Aligns given value down to nearest multiply of align value. For example: VmaAlignUp(11, 8) = 8.
// Use types like uint32_t, uint64_t as T.
template <typename T>
static inline T VmaAlignDown(T val, T alignment)
{
    VMA_HEAVY_ASSERT(VmaIsPow2(alignment));
    return val & ~(alignment - 1);
}

// Division with mathematical rounding to nearest number.
template <typename T>
static inline T VmaRoundDiv(T x, T y)
{
    return (x + (y / (T)2)) / y;
}

// Divide by 'y' and round up to nearest integer.
template <typename T>
static inline T VmaDivideRoundingUp(T x, T y)
{
    return (x + y - (T)1) / y;
}

// Returns smallest power of 2 greater or equal to v.
static inline uint32_t VmaNextPow2(uint32_t v)
{
    v--;
    v |= v >> 1;
    v |= v >> 2;
    v |= v >> 4;
    v |= v >> 8;
    v |= v >> 16;
    v++;
    return v;
}

static inline uint64_t VmaNextPow2(uint64_t v)
{
    v--;
    v |= v >> 1;
    v |= v >> 2;
    v |= v >> 4;
    v |= v >> 8;
    v |= v >> 16;
    v |= v >> 32;
    v++;
    return v;
}

// Returns largest power of 2 less or equal to v.
static inline uint32_t VmaPrevPow2(uint32_t v)
{
    v |= v >> 1;
    v |= v >> 2;
    v |= v >> 4;
    v |= v >> 8;
    v |= v >> 16;
    v = v ^ (v >> 1);
    return v;
}

static inline uint64_t VmaPrevPow2(uint64_t v)
{
    v |= v >> 1;
    v |= v >> 2;
    v |= v >> 4;
    v |= v >> 8;
    v |= v >> 16;
    v |= v >> 32;
    v = v ^ (v >> 1);
    return v;
}

static inline bool VmaStrIsEmpty(const char* pStr)
{
    return pStr == VMA_NULL || *pStr == '\0';
}

/*
Returns true if two memory blocks occupy overlapping pages.
ResourceA must be in less memory offset than ResourceB.

Algorithm is based on "Vulkan 1.0.39 - A Specification (with all registered Vulkan extensions)"
chapter 11.6 "Resource Memory Association", paragraph "Buffer-Image Granularity".
*/
static inline bool VmaBlocksOnSamePage(
    VkDeviceSize resourceAOffset,
    VkDeviceSize resourceASize,
    VkDeviceSize resourceBOffset,
    VkDeviceSize pageSize)
{
    VMA_ASSERT(resourceAOffset + resourceASize <= resourceBOffset && resourceASize > 0 && pageSize > 0);
    VkDeviceSize resourceAEnd = resourceAOffset + resourceASize - 1;
    VkDeviceSize resourceAEndPage = resourceAEnd & ~(pageSize - 1);
    VkDeviceSize resourceBStart = resourceBOffset;
    VkDeviceSize resourceBStartPage = resourceBStart & ~(pageSize - 1);
    return resourceAEndPage == resourceBStartPage;
}

/*
Returns true if given suballocation types could conflict and must respect
VkPhysicalDeviceLimits::bufferImageGranularity. They conflict if one is buffer
or linear image and another one is optimal image. If type is unknown, behave
conservatively.
*/
static inline bool VmaIsBufferImageGranularityConflict(
    VmaSuballocationType suballocType1,
    VmaSuballocationType suballocType2)
{
    if (suballocType1 > suballocType2)
    {
        VMA_SWAP(suballocType1, suballocType2);
    }

    switch (suballocType1)
    {
    case VMA_SUBALLOCATION_TYPE_FREE:
        return false;
    case VMA_SUBALLOCATION_TYPE_UNKNOWN:
        return true;
    case VMA_SUBALLOCATION_TYPE_BUFFER:
        return
            suballocType2 == VMA_SUBALLOCATION_TYPE_IMAGE_UNKNOWN ||
            suballocType2 == VMA_SUBALLOCATION_TYPE_IMAGE_OPTIMAL;
    case VMA_SUBALLOCATION_TYPE_IMAGE_UNKNOWN:
        return
            suballocType2 == VMA_SUBALLOCATION_TYPE_IMAGE_UNKNOWN ||
            suballocType2 == VMA_SUBALLOCATION_TYPE_IMAGE_LINEAR ||
            suballocType2 == VMA_SUBALLOCATION_TYPE_IMAGE_OPTIMAL;
    case VMA_SUBALLOCATION_TYPE_IMAGE_LINEAR:
        return
            suballocType2 == VMA_SUBALLOCATION_TYPE_IMAGE_OPTIMAL;
    case VMA_SUBALLOCATION_TYPE_IMAGE_OPTIMAL:
        return false;
    default:
        VMA_ASSERT(0);
        return true;
    }
}

static void VmaWriteMagicValue(void* pData, VkDeviceSize offset)
{
#if VMA_DEBUG_MARGIN > 0 && VMA_DEBUG_DETECT_CORRUPTION
    uint32_t* pDst = (uint32_t*)((char*)pData + offset);
    const size_t numberCount = VMA_DEBUG_MARGIN / sizeof(uint32_t);
    for (size_t i = 0; i < numberCount; ++i, ++pDst)
    {
        *pDst = VMA_CORRUPTION_DETECTION_MAGIC_VALUE;
    }
#else
    // no-op
#endif
}

static bool VmaValidateMagicValue(const void* pData, VkDeviceSize offset)
{
#if VMA_DEBUG_MARGIN > 0 && VMA_DEBUG_DETECT_CORRUPTION
    const uint32_t* pSrc = (const uint32_t*)((const char*)pData + offset);
    const size_t numberCount = VMA_DEBUG_MARGIN / sizeof(uint32_t);
    for (size_t i = 0; i < numberCount; ++i, ++pSrc)
    {
        if (*pSrc != VMA_CORRUPTION_DETECTION_MAGIC_VALUE)
        {
            return false;
        }
    }
#endif
    return true;
}

/*
Fills structure with parameters of an example buffer to be used for transfers
during GPU memory defragmentation.
*/
static void VmaFillGpuDefragmentationBufferCreateInfo(VkBufferCreateInfo& outBufCreateInfo)
{
    memset(&outBufCreateInfo, 0, sizeof(outBufCreateInfo));
    outBufCreateInfo.sType = VK_STRUCTURE_TYPE_BUFFER_CREATE_INFO;
    outBufCreateInfo.usage = VK_BUFFER_USAGE_TRANSFER_SRC_BIT | VK_BUFFER_USAGE_TRANSFER_DST_BIT;
    outBufCreateInfo.size = (VkDeviceSize)VMA_DEFAULT_LARGE_HEAP_BLOCK_SIZE; // Example size.
}


/*
Performs binary search and returns iterator to first element that is greater or
equal to (key), according to comparison (cmp).

Cmp should return true if first argument is less than second argument.

Returned value is the found element, if present in the collection or place where
new element with value (key) should be inserted.
*/
template <typename CmpLess, typename IterT, typename KeyT>
static IterT VmaBinaryFindFirstNotLess(IterT beg, IterT end, const KeyT& key, const CmpLess& cmp)
{
    size_t down = 0, up = (end - beg);
    while (down < up)
    {
        const size_t mid = down + (up - down) / 2;  // Overflow-safe midpoint calculation
        if (cmp(*(beg + mid), key))
        {
            down = mid + 1;
        }
        else
        {
            up = mid;
        }
    }
    return beg + down;
}

template<typename CmpLess, typename IterT, typename KeyT>
IterT VmaBinaryFindSorted(const IterT& beg, const IterT& end, const KeyT& value, const CmpLess& cmp)
{
    IterT it = VmaBinaryFindFirstNotLess<CmpLess, IterT, KeyT>(
        beg, end, value, cmp);
    if (it == end ||
        (!cmp(*it, value) && !cmp(value, *it)))
    {
        return it;
    }
    return end;
}

/*
Returns true if all pointers in the array are not-null and unique.
Warning! O(n^2) complexity. Use only inside VMA_HEAVY_ASSERT.
T must be pointer type, e.g. VmaAllocation, VmaPool.
*/
template<typename T>
static bool VmaValidatePointerArray(uint32_t count, const T* arr)
{
    for (uint32_t i = 0; i < count; ++i)
    {
        const T iPtr = arr[i];
        if (iPtr == VMA_NULL)
        {
            return false;
        }
        for (uint32_t j = i + 1; j < count; ++j)
        {
            if (iPtr == arr[j])
            {
                return false;
            }
        }
    }
    return true;
}

template<typename MainT, typename NewT>
static inline void VmaPnextChainPushFront(MainT* mainStruct, NewT* newStruct)
{
    newStruct->pNext = mainStruct->pNext;
    mainStruct->pNext = newStruct;
}

// This is the main algorithm that guides the selection of a memory type best for an allocation -
// converts usage to required/preferred/not preferred flags.
static bool FindMemoryPreferences(
    bool isIntegratedGPU,
    const VmaAllocationCreateInfo& allocCreateInfo,
    VkFlags bufImgUsage, // VkBufferCreateInfo::usage or VkImageCreateInfo::usage. UINT32_MAX if unknown.
    VkMemoryPropertyFlags& outRequiredFlags,
    VkMemoryPropertyFlags& outPreferredFlags,
    VkMemoryPropertyFlags& outNotPreferredFlags)
{
    outRequiredFlags = allocCreateInfo.requiredFlags;
    outPreferredFlags = allocCreateInfo.preferredFlags;
    outNotPreferredFlags = 0;

    switch(allocCreateInfo.usage)
    {
    case VMA_MEMORY_USAGE_UNKNOWN:
        break;
    case VMA_MEMORY_USAGE_GPU_ONLY:
        if(!isIntegratedGPU || (outPreferredFlags & VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT) == 0)
        {
            outPreferredFlags |= VK_MEMORY_PROPERTY_DEVICE_LOCAL_BIT;
        }
        break;
    case VMA_MEMORY_USAGE_CPU_ONLY:
        outRequiredFlags |= VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT | VK_MEMORY_PROPERTY_HOST_COHERENT_BIT;
        break;
    case VMA_MEMORY_USAGE_CPU_TO_GPU:
        outRequiredFlags |= VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT;
        if(!isIntegratedGPU || (outPreferredFlags & VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT) == 0)
        {
            outPreferredFlags |= VK_MEMORY_PROPERTY_DEVICE_LOCAL_BIT;
        }
        break;
    case VMA_MEMORY_USAGE_GPU_TO_CPU:
        outRequiredFlags |= VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT;
        outPreferredFlags |= VK_MEMORY_PROPERTY_HOST_CACHED_BIT;
        break;
    case VMA_MEMORY_USAGE_CPU_COPY:
        outNotPreferredFlags |= VK_MEMORY_PROPERTY_DEVICE_LOCAL_BIT;
        break;
    case VMA_MEMORY_USAGE_GPU_LAZILY_ALLOCATED:
        outRequiredFlags |= VK_MEMORY_PROPERTY_LAZILY_ALLOCATED_BIT;
        break;
    case VMA_MEMORY_USAGE_AUTO:
    case VMA_MEMORY_USAGE_AUTO_PREFER_DEVICE:
    case VMA_MEMORY_USAGE_AUTO_PREFER_HOST:
    {
        if(bufImgUsage == UINT32_MAX)
        {
            VMA_ASSERT(0 && "VMA_MEMORY_USAGE_AUTO* values can only be used with functions like vmaCreateBuffer, vmaCreateImage so that the details of the created resource are known.");
            return false;
        }
        // This relies on values of VK_IMAGE_USAGE_TRANSFER* being the same VK_BUFFER_IMAGE_TRANSFER*.
        const bool deviceAccess = (bufImgUsage & ~(VK_BUFFER_USAGE_TRANSFER_DST_BIT | VK_BUFFER_USAGE_TRANSFER_SRC_BIT)) != 0;
        const bool hostAccessSequentialWrite = (allocCreateInfo.flags & VMA_ALLOCATION_CREATE_HOST_ACCESS_SEQUENTIAL_WRITE_BIT) != 0;
        const bool hostAccessRandom = (allocCreateInfo.flags & VMA_ALLOCATION_CREATE_HOST_ACCESS_RANDOM_BIT) != 0;
        const bool hostAccessAllowTransferInstead = (allocCreateInfo.flags & VMA_ALLOCATION_CREATE_HOST_ACCESS_ALLOW_TRANSFER_INSTEAD_BIT) != 0;
        const bool preferDevice = allocCreateInfo.usage == VMA_MEMORY_USAGE_AUTO_PREFER_DEVICE;
        const bool preferHost = allocCreateInfo.usage == VMA_MEMORY_USAGE_AUTO_PREFER_HOST;

        // CPU random access - e.g. a buffer written to or transferred from GPU to read back on CPU.
        if(hostAccessRandom)
        {
            if(!isIntegratedGPU && deviceAccess && hostAccessAllowTransferInstead && !preferHost)
            {
                // Nice if it will end up in HOST_VISIBLE, but more importantly prefer DEVICE_LOCAL.
                // Omitting HOST_VISIBLE here is intentional.
                // In case there is DEVICE_LOCAL | HOST_VISIBLE | HOST_CACHED, it will pick that one.
                // Otherwise, this will give same weight to DEVICE_LOCAL as HOST_VISIBLE | HOST_CACHED and select the former if occurs first on the list.
                outPreferredFlags |= VK_MEMORY_PROPERTY_DEVICE_LOCAL_BIT | VK_MEMORY_PROPERTY_HOST_CACHED_BIT;
            }
            else
            {
                // Always CPU memory, cached.
                outRequiredFlags |= VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT | VK_MEMORY_PROPERTY_HOST_CACHED_BIT;
            }
        }
        // CPU sequential write - may be CPU or host-visible GPU memory, uncached and write-combined.
        else if(hostAccessSequentialWrite)
        {
            // Want uncached and write-combined.
            outNotPreferredFlags |= VK_MEMORY_PROPERTY_HOST_CACHED_BIT;

            if(!isIntegratedGPU && deviceAccess && hostAccessAllowTransferInstead && !preferHost)
            {
                outPreferredFlags |= VK_MEMORY_PROPERTY_DEVICE_LOCAL_BIT | VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT;
            }
            else
            {
                outRequiredFlags |= VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT;
                // Direct GPU access, CPU sequential write (e.g. a dynamic uniform buffer updated every frame)
                if(deviceAccess)
                {
                    // Could go to CPU memory or GPU BAR/unified. Up to the user to decide. If no preference, choose GPU memory.
                    if(preferHost)
                        outNotPreferredFlags |= VK_MEMORY_PROPERTY_DEVICE_LOCAL_BIT;
                    else
                        outPreferredFlags |= VK_MEMORY_PROPERTY_DEVICE_LOCAL_BIT;
                }
                // GPU no direct access, CPU sequential write (e.g. an upload buffer to be transferred to the GPU)
                else
                {
                    // Could go to CPU memory or GPU BAR/unified. Up to the user to decide. If no preference, choose CPU memory.
                    if(preferDevice)
                        outPreferredFlags |= VK_MEMORY_PROPERTY_DEVICE_LOCAL_BIT;
                    else
                        outNotPreferredFlags |= VK_MEMORY_PROPERTY_DEVICE_LOCAL_BIT;
                }
            }
        }
        // No CPU access
        else
        {
            // GPU access, no CPU access (e.g. a color attachment image) - prefer GPU memory
            if(deviceAccess)
            {
                // ...unless there is a clear preference from the user not to do so.
                if(preferHost)
                    outNotPreferredFlags |= VK_MEMORY_PROPERTY_DEVICE_LOCAL_BIT;
                else
                    outPreferredFlags |= VK_MEMORY_PROPERTY_DEVICE_LOCAL_BIT;
            }
            // No direct GPU access, no CPU access, just transfers.
            // It may be staging copy intended for e.g. preserving image for next frame (then better GPU memory) or
            // a "swap file" copy to free some GPU memory (then better CPU memory).
            // Up to the user to decide. If no preferece, assume the former and choose GPU memory.
            if(preferHost)
                outNotPreferredFlags |= VK_MEMORY_PROPERTY_DEVICE_LOCAL_BIT;
            else
                outPreferredFlags |= VK_MEMORY_PROPERTY_DEVICE_LOCAL_BIT;
        }
        break;
    }
    default:
        VMA_ASSERT(0);
    }

    // Avoid DEVICE_COHERENT unless explicitly requested.
    if(((allocCreateInfo.requiredFlags | allocCreateInfo.preferredFlags) &
        (VK_MEMORY_PROPERTY_DEVICE_COHERENT_BIT_AMD_COPY | VK_MEMORY_PROPERTY_DEVICE_UNCACHED_BIT_AMD_COPY)) == 0)
    {
        outNotPreferredFlags |= VK_MEMORY_PROPERTY_DEVICE_UNCACHED_BIT_AMD_COPY;
    }

    return true;
}

////////////////////////////////////////////////////////////////////////////////
// Memory allocation

static void* VmaMalloc(const VkAllocationCallbacks* pAllocationCallbacks, size_t size, size_t alignment)
{
    void* result = VMA_NULL;
    if ((pAllocationCallbacks != VMA_NULL) &&
        (pAllocationCallbacks->pfnAllocation != VMA_NULL))
    {
        result = (*pAllocationCallbacks->pfnAllocation)(
            pAllocationCallbacks->pUserData,
            size,
            alignment,
            VK_SYSTEM_ALLOCATION_SCOPE_OBJECT);
    }
    else
    {
        result = VMA_SYSTEM_ALIGNED_MALLOC(size, alignment);
    }
    VMA_ASSERT(result != VMA_NULL && "CPU memory allocation failed.");
    return result;
}

static void VmaFree(const VkAllocationCallbacks* pAllocationCallbacks, void* ptr)
{
    if ((pAllocationCallbacks != VMA_NULL) &&
        (pAllocationCallbacks->pfnFree != VMA_NULL))
    {
        (*pAllocationCallbacks->pfnFree)(pAllocationCallbacks->pUserData, ptr);
    }
    else
    {
        VMA_SYSTEM_ALIGNED_FREE(ptr);
    }
}

template<typename T>
static T* VmaAllocate(const VkAllocationCallbacks* pAllocationCallbacks)
{
    return (T*)VmaMalloc(pAllocationCallbacks, sizeof(T), VMA_ALIGN_OF(T));
}

template<typename T>
static T* VmaAllocateArray(const VkAllocationCallbacks* pAllocationCallbacks, size_t count)
{
    return (T*)VmaMalloc(pAllocationCallbacks, sizeof(T) * count, VMA_ALIGN_OF(T));
}

#define vma_new(allocator, type)   new(VmaAllocate<type>(allocator))(type)

#define vma_new_array(allocator, type, count)   new(VmaAllocateArray<type>((allocator), (count)))(type)

template<typename T>
static void vma_delete(const VkAllocationCallbacks* pAllocationCallbacks, T* ptr)
{
    ptr->~T();
    VmaFree(pAllocationCallbacks, ptr);
}

template<typename T>
static void vma_delete_array(const VkAllocationCallbacks* pAllocationCallbacks, T* ptr, size_t count)
{
    if (ptr != VMA_NULL)
    {
        for (size_t i = count; i--; )
        {
            ptr[i].~T();
        }
        VmaFree(pAllocationCallbacks, ptr);
    }
}

static char* VmaCreateStringCopy(const VkAllocationCallbacks* allocs, const char* srcStr)
{
    if (srcStr != VMA_NULL)
    {
        const size_t len = strlen(srcStr);
        char* const result = vma_new_array(allocs, char, len + 1);
        memcpy(result, srcStr, len + 1);
        return result;
    }
    return VMA_NULL;
}

#if VMA_STATS_STRING_ENABLED
static char* VmaCreateStringCopy(const VkAllocationCallbacks* allocs, const char* srcStr, size_t strLen)
{
    if (srcStr != VMA_NULL)
    {
        char* const result = vma_new_array(allocs, char, strLen + 1);
        memcpy(result, srcStr, strLen);
        result[strLen] = '\0';
        return result;
    }
    return VMA_NULL;
}
#endif // VMA_STATS_STRING_ENABLED

static void VmaFreeString(const VkAllocationCallbacks* allocs, char* str)
{
    if (str != VMA_NULL)
    {
        const size_t len = strlen(str);
        vma_delete_array(allocs, str, len + 1);
    }
}

template<typename CmpLess, typename VectorT>
size_t VmaVectorInsertSorted(VectorT& vector, const typename VectorT::value_type& value)
{
    const size_t indexToInsert = VmaBinaryFindFirstNotLess(
        vector.data(),
        vector.data() + vector.size(),
        value,
        CmpLess()) - vector.data();
    VmaVectorInsert(vector, indexToInsert, value);
    return indexToInsert;
}

template<typename CmpLess, typename VectorT>
bool VmaVectorRemoveSorted(VectorT& vector, const typename VectorT::value_type& value)
{
    CmpLess comparator;
    typename VectorT::iterator it = VmaBinaryFindFirstNotLess(
        vector.begin(),
        vector.end(),
        value,
        comparator);
    if ((it != vector.end()) && !comparator(*it, value) && !comparator(value, *it))
    {
        size_t indexToRemove = it - vector.begin();
        VmaVectorRemove(vector, indexToRemove);
        return true;
    }
    return false;
}
#endif // _VMA_FUNCTIONS

#ifndef _VMA_STATISTICS_FUNCTIONS

static void VmaClearStatistics(VmaStatistics& outStats)
{
    outStats.blockCount = 0;
    outStats.allocationCount = 0;
    outStats.blockBytes = 0;
    outStats.allocationBytes = 0;
}

static void VmaAddStatistics(VmaStatistics& inoutStats, const VmaStatistics& src)
{
    inoutStats.blockCount += src.blockCount;
    inoutStats.allocationCount += src.allocationCount;
    inoutStats.blockBytes += src.blockBytes;
    inoutStats.allocationBytes += src.allocationBytes;
}

static void VmaClearDetailedStatistics(VmaDetailedStatistics& outStats)
{
    VmaClearStatistics(outStats.statistics);
    outStats.unusedRangeCount = 0;
    outStats.allocationSizeMin = VK_WHOLE_SIZE;
    outStats.allocationSizeMax = 0;
    outStats.unusedRangeSizeMin = VK_WHOLE_SIZE;
    outStats.unusedRangeSizeMax = 0;
}

static void VmaAddDetailedStatisticsAllocation(VmaDetailedStatistics& inoutStats, VkDeviceSize size)
{
    inoutStats.statistics.allocationCount++;
    inoutStats.statistics.allocationBytes += size;
    inoutStats.allocationSizeMin = VMA_MIN(inoutStats.allocationSizeMin, size);
    inoutStats.allocationSizeMax = VMA_MAX(inoutStats.allocationSizeMax, size);
}

static void VmaAddDetailedStatisticsUnusedRange(VmaDetailedStatistics& inoutStats, VkDeviceSize size)
{
    inoutStats.unusedRangeCount++;
    inoutStats.unusedRangeSizeMin = VMA_MIN(inoutStats.unusedRangeSizeMin, size);
    inoutStats.unusedRangeSizeMax = VMA_MAX(inoutStats.unusedRangeSizeMax, size);
}

static void VmaAddDetailedStatistics(VmaDetailedStatistics& inoutStats, const VmaDetailedStatistics& src)
{
    VmaAddStatistics(inoutStats.statistics, src.statistics);
    inoutStats.unusedRangeCount += src.unusedRangeCount;
    inoutStats.allocationSizeMin = VMA_MIN(inoutStats.allocationSizeMin, src.allocationSizeMin);
    inoutStats.allocationSizeMax = VMA_MAX(inoutStats.allocationSizeMax, src.allocationSizeMax);
    inoutStats.unusedRangeSizeMin = VMA_MIN(inoutStats.unusedRangeSizeMin, src.unusedRangeSizeMin);
    inoutStats.unusedRangeSizeMax = VMA_MAX(inoutStats.unusedRangeSizeMax, src.unusedRangeSizeMax);
}

#endif // _VMA_STATISTICS_FUNCTIONS

#ifndef _VMA_MUTEX_LOCK
// Helper RAII class to lock a mutex in constructor and unlock it in destructor (at the end of scope).
struct VmaMutexLock
{
    VMA_CLASS_NO_COPY(VmaMutexLock)
public:
    VmaMutexLock(VMA_MUTEX& mutex, bool useMutex = true) :
        m_pMutex(useMutex ? &mutex : VMA_NULL)
    {
        if (m_pMutex) { m_pMutex->Lock(); }
    }
    ~VmaMutexLock() {  if (m_pMutex) { m_pMutex->Unlock(); } }

private:
    VMA_MUTEX* m_pMutex;
};

// Helper RAII class to lock a RW mutex in constructor and unlock it in destructor (at the end of scope), for reading.
struct VmaMutexLockRead
{
    VMA_CLASS_NO_COPY(VmaMutexLockRead)
public:
    VmaMutexLockRead(VMA_RW_MUTEX& mutex, bool useMutex) :
        m_pMutex(useMutex ? &mutex : VMA_NULL)
    {
        if (m_pMutex) { m_pMutex->LockRead(); }
    }
    ~VmaMutexLockRead() { if (m_pMutex) { m_pMutex->UnlockRead(); } }

private:
    VMA_RW_MUTEX* m_pMutex;
};

// Helper RAII class to lock a RW mutex in constructor and unlock it in destructor (at the end of scope), for writing.
struct VmaMutexLockWrite
{
    VMA_CLASS_NO_COPY(VmaMutexLockWrite)
public:
    VmaMutexLockWrite(VMA_RW_MUTEX& mutex, bool useMutex)
        : m_pMutex(useMutex ? &mutex : VMA_NULL)
    {
        if (m_pMutex) { m_pMutex->LockWrite(); }
    }
    ~VmaMutexLockWrite() { if (m_pMutex) { m_pMutex->UnlockWrite(); } }

private:
    VMA_RW_MUTEX* m_pMutex;
};

#if VMA_DEBUG_GLOBAL_MUTEX
    static VMA_MUTEX gDebugGlobalMutex;
    #define VMA_DEBUG_GLOBAL_MUTEX_LOCK VmaMutexLock debugGlobalMutexLock(gDebugGlobalMutex, true);
#else
    #define VMA_DEBUG_GLOBAL_MUTEX_LOCK
#endif
#endif // _VMA_MUTEX_LOCK

#ifndef _VMA_ATOMIC_TRANSACTIONAL_INCREMENT
// An object that increments given atomic but decrements it back in the destructor unless Commit() is called.
template<typename T>
struct AtomicTransactionalIncrement
{
public:
    typedef std::atomic<T> AtomicT;

    ~AtomicTransactionalIncrement()
    {
        if(m_Atomic)
            --(*m_Atomic);
    }

    void Commit() { m_Atomic = nullptr; }
    T Increment(AtomicT* atomic)
    {
        m_Atomic = atomic;
        return m_Atomic->fetch_add(1);
    }

private:
    AtomicT* m_Atomic = nullptr;
};
#endif // _VMA_ATOMIC_TRANSACTIONAL_INCREMENT

#ifndef _VMA_STL_ALLOCATOR
// STL-compatible allocator.
template<typename T>
struct VmaStlAllocator
{
    const VkAllocationCallbacks* const m_pCallbacks;
    typedef T value_type;

    VmaStlAllocator(const VkAllocationCallbacks* pCallbacks) : m_pCallbacks(pCallbacks) {}
    template<typename U>
    VmaStlAllocator(const VmaStlAllocator<U>& src) : m_pCallbacks(src.m_pCallbacks) {}
    VmaStlAllocator(const VmaStlAllocator&) = default;
    VmaStlAllocator& operator=(const VmaStlAllocator&) = delete;

    T* allocate(size_t n) { return VmaAllocateArray<T>(m_pCallbacks, n); }
    void deallocate(T* p, size_t n) { VmaFree(m_pCallbacks, p); }

    template<typename U>
    bool operator==(const VmaStlAllocator<U>& rhs) const
    {
        return m_pCallbacks == rhs.m_pCallbacks;
    }
    template<typename U>
    bool operator!=(const VmaStlAllocator<U>& rhs) const
    {
        return m_pCallbacks != rhs.m_pCallbacks;
    }
};
#endif // _VMA_STL_ALLOCATOR

#ifndef _VMA_VECTOR
/* Class with interface compatible with subset of std::vector.
T must be POD because constructors and destructors are not called and memcpy is
used for these objects. */
template<typename T, typename AllocatorT>
class VmaVector
{
public:
    typedef T value_type;
    typedef T* iterator;
    typedef const T* const_iterator;

    VmaVector(const AllocatorT& allocator);
    VmaVector(size_t count, const AllocatorT& allocator);
    // This version of the constructor is here for compatibility with pre-C++14 std::vector.
    // value is unused.
    VmaVector(size_t count, const T& value, const AllocatorT& allocator) : VmaVector(count, allocator) {}
    VmaVector(const VmaVector<T, AllocatorT>& src);
    VmaVector& operator=(const VmaVector& rhs);
    ~VmaVector() { VmaFree(m_Allocator.m_pCallbacks, m_pArray); }

    bool empty() const { return m_Count == 0; }
    size_t size() const { return m_Count; }
    T* data() { return m_pArray; }
    T& front() { VMA_HEAVY_ASSERT(m_Count > 0); return m_pArray[0]; }
    T& back() { VMA_HEAVY_ASSERT(m_Count > 0); return m_pArray[m_Count - 1]; }
    const T* data() const { return m_pArray; }
    const T& front() const { VMA_HEAVY_ASSERT(m_Count > 0); return m_pArray[0]; }
    const T& back() const { VMA_HEAVY_ASSERT(m_Count > 0); return m_pArray[m_Count - 1]; }

    iterator begin() { return m_pArray; }
    iterator end() { return m_pArray + m_Count; }
    const_iterator cbegin() const { return m_pArray; }
    const_iterator cend() const { return m_pArray + m_Count; }
    const_iterator begin() const { return cbegin(); }
    const_iterator end() const { return cend(); }

    void pop_front() { VMA_HEAVY_ASSERT(m_Count > 0); remove(0); }
    void pop_back() { VMA_HEAVY_ASSERT(m_Count > 0); resize(size() - 1); }
    void push_front(const T& src) { insert(0, src); }

    void push_back(const T& src);
    void reserve(size_t newCapacity, bool freeMemory = false);
    void resize(size_t newCount);
    void clear() { resize(0); }
    void shrink_to_fit();
    void insert(size_t index, const T& src);
    void remove(size_t index);

    T& operator[](size_t index) { VMA_HEAVY_ASSERT(index < m_Count); return m_pArray[index]; }
    const T& operator[](size_t index) const { VMA_HEAVY_ASSERT(index < m_Count); return m_pArray[index]; }

private:
    AllocatorT m_Allocator;
    T* m_pArray;
    size_t m_Count;
    size_t m_Capacity;
};

#ifndef _VMA_VECTOR_FUNCTIONS
template<typename T, typename AllocatorT>
VmaVector<T, AllocatorT>::VmaVector(const AllocatorT& allocator)
    : m_Allocator(allocator),
    m_pArray(VMA_NULL),
    m_Count(0),
    m_Capacity(0) {}

template<typename T, typename AllocatorT>
VmaVector<T, AllocatorT>::VmaVector(size_t count, const AllocatorT& allocator)
    : m_Allocator(allocator),
    m_pArray(count ? (T*)VmaAllocateArray<T>(allocator.m_pCallbacks, count) : VMA_NULL),
    m_Count(count),
    m_Capacity(count) {}

template<typename T, typename AllocatorT>
VmaVector<T, AllocatorT>::VmaVector(const VmaVector& src)
    : m_Allocator(src.m_Allocator),
    m_pArray(src.m_Count ? (T*)VmaAllocateArray<T>(src.m_Allocator.m_pCallbacks, src.m_Count) : VMA_NULL),
    m_Count(src.m_Count),
    m_Capacity(src.m_Count)
{
    if (m_Count != 0)
    {
        memcpy(m_pArray, src.m_pArray, m_Count * sizeof(T));
    }
}

template<typename T, typename AllocatorT>
VmaVector<T, AllocatorT>& VmaVector<T, AllocatorT>::operator=(const VmaVector& rhs)
{
    if (&rhs != this)
    {
        resize(rhs.m_Count);
        if (m_Count != 0)
        {
            memcpy(m_pArray, rhs.m_pArray, m_Count * sizeof(T));
        }
    }
    return *this;
}

template<typename T, typename AllocatorT>
void VmaVector<T, AllocatorT>::push_back(const T& src)
{
    const size_t newIndex = size();
    resize(newIndex + 1);
    m_pArray[newIndex] = src;
}

template<typename T, typename AllocatorT>
void VmaVector<T, AllocatorT>::reserve(size_t newCapacity, bool freeMemory)
{
    newCapacity = VMA_MAX(newCapacity, m_Count);

    if ((newCapacity < m_Capacity) && !freeMemory)
    {
        newCapacity = m_Capacity;
    }

    if (newCapacity != m_Capacity)
    {
        T* const newArray = newCapacity ? VmaAllocateArray<T>(m_Allocator, newCapacity) : VMA_NULL;
        if (m_Count != 0)
        {
            memcpy(newArray, m_pArray, m_Count * sizeof(T));
        }
        VmaFree(m_Allocator.m_pCallbacks, m_pArray);
        m_Capacity = newCapacity;
        m_pArray = newArray;
    }
}

template<typename T, typename AllocatorT>
void VmaVector<T, AllocatorT>::resize(size_t newCount)
{
    size_t newCapacity = m_Capacity;
    if (newCount > m_Capacity)
    {
        newCapacity = VMA_MAX(newCount, VMA_MAX(m_Capacity * 3 / 2, (size_t)8));
    }

    if (newCapacity != m_Capacity)
    {
        T* const newArray = newCapacity ? VmaAllocateArray<T>(m_Allocator.m_pCallbacks, newCapacity) : VMA_NULL;
        const size_t elementsToCopy = VMA_MIN(m_Count, newCount);
        if (elementsToCopy != 0)
        {
            memcpy(newArray, m_pArray, elementsToCopy * sizeof(T));
        }
        VmaFree(m_Allocator.m_pCallbacks, m_pArray);
        m_Capacity = newCapacity;
        m_pArray = newArray;
    }

    m_Count = newCount;
}

template<typename T, typename AllocatorT>
void VmaVector<T, AllocatorT>::shrink_to_fit()
{
    if (m_Capacity > m_Count)
    {
        T* newArray = VMA_NULL;
        if (m_Count > 0)
        {
            newArray = VmaAllocateArray<T>(m_Allocator.m_pCallbacks, m_Count);
            memcpy(newArray, m_pArray, m_Count * sizeof(T));
        }
        VmaFree(m_Allocator.m_pCallbacks, m_pArray);
        m_Capacity = m_Count;
        m_pArray = newArray;
    }
}

template<typename T, typename AllocatorT>
void VmaVector<T, AllocatorT>::insert(size_t index, const T& src)
{
    VMA_HEAVY_ASSERT(index <= m_Count);
    const size_t oldCount = size();
    resize(oldCount + 1);
    if (index < oldCount)
    {
        memmove(m_pArray + (index + 1), m_pArray + index, (oldCount - index) * sizeof(T));
    }
    m_pArray[index] = src;
}

template<typename T, typename AllocatorT>
void VmaVector<T, AllocatorT>::remove(size_t index)
{
    VMA_HEAVY_ASSERT(index < m_Count);
    const size_t oldCount = size();
    if (index < oldCount - 1)
    {
        memmove(m_pArray + index, m_pArray + (index + 1), (oldCount - index - 1) * sizeof(T));
    }
    resize(oldCount - 1);
}
#endif // _VMA_VECTOR_FUNCTIONS

template<typename T, typename allocatorT>
static void VmaVectorInsert(VmaVector<T, allocatorT>& vec, size_t index, const T& item)
{
    vec.insert(index, item);
}

template<typename T, typename allocatorT>
static void VmaVectorRemove(VmaVector<T, allocatorT>& vec, size_t index)
{
    vec.remove(index);
}
#endif // _VMA_VECTOR

#ifndef _VMA_SMALL_VECTOR
/*
This is a vector (a variable-sized array), optimized for the case when the array is small.

It contains some number of elements in-place, which allows it to avoid heap allocation
when the actual number of elements is below that threshold. This allows normal "small"
cases to be fast without losing generality for large inputs.
*/
template<typename T, typename AllocatorT, size_t N>
class VmaSmallVector
{
public:
    typedef T value_type;
    typedef T* iterator;

    VmaSmallVector(const AllocatorT& allocator);
    VmaSmallVector(size_t count, const AllocatorT& allocator);
    template<typename SrcT, typename SrcAllocatorT, size_t SrcN>
    VmaSmallVector(const VmaSmallVector<SrcT, SrcAllocatorT, SrcN>&) = delete;
    template<typename SrcT, typename SrcAllocatorT, size_t SrcN>
    VmaSmallVector<T, AllocatorT, N>& operator=(const VmaSmallVector<SrcT, SrcAllocatorT, SrcN>&) = delete;
    ~VmaSmallVector() = default;

    bool empty() const { return m_Count == 0; }
    size_t size() const { return m_Count; }
    T* data() { return m_Count > N ? m_DynamicArray.data() : m_StaticArray; }
    T& front() { VMA_HEAVY_ASSERT(m_Count > 0); return data()[0]; }
    T& back() { VMA_HEAVY_ASSERT(m_Count > 0); return data()[m_Count - 1]; }
    const T* data() const { return m_Count > N ? m_DynamicArray.data() : m_StaticArray; }
    const T& front() const { VMA_HEAVY_ASSERT(m_Count > 0); return data()[0]; }
    const T& back() const { VMA_HEAVY_ASSERT(m_Count > 0); return data()[m_Count - 1]; }

    iterator begin() { return data(); }
    iterator end() { return data() + m_Count; }

    void pop_front() { VMA_HEAVY_ASSERT(m_Count > 0); remove(0); }
    void pop_back() { VMA_HEAVY_ASSERT(m_Count > 0); resize(size() - 1); }
    void push_front(const T& src) { insert(0, src); }

    void push_back(const T& src);
    void resize(size_t newCount, bool freeMemory = false);
    void clear(bool freeMemory = false);
    void insert(size_t index, const T& src);
    void remove(size_t index);

    T& operator[](size_t index) { VMA_HEAVY_ASSERT(index < m_Count); return data()[index]; }
    const T& operator[](size_t index) const { VMA_HEAVY_ASSERT(index < m_Count); return data()[index]; }

private:
    size_t m_Count;
    T m_StaticArray[N]; // Used when m_Size <= N
    VmaVector<T, AllocatorT> m_DynamicArray; // Used when m_Size > N
};

#ifndef _VMA_SMALL_VECTOR_FUNCTIONS
template<typename T, typename AllocatorT, size_t N>
VmaSmallVector<T, AllocatorT, N>::VmaSmallVector(const AllocatorT& allocator)
    : m_Count(0),
    m_DynamicArray(allocator) {}

template<typename T, typename AllocatorT, size_t N>
VmaSmallVector<T, AllocatorT, N>::VmaSmallVector(size_t count, const AllocatorT& allocator)
    : m_Count(count),
    m_DynamicArray(count > N ? count : 0, allocator) {}

template<typename T, typename AllocatorT, size_t N>
void VmaSmallVector<T, AllocatorT, N>::push_back(const T& src)
{
    const size_t newIndex = size();
    resize(newIndex + 1);
    data()[newIndex] = src;
}

template<typename T, typename AllocatorT, size_t N>
void VmaSmallVector<T, AllocatorT, N>::resize(size_t newCount, bool freeMemory)
{
    if (newCount > N && m_Count > N)
    {
        // Any direction, staying in m_DynamicArray
        m_DynamicArray.resize(newCount);
        if (freeMemory)
        {
            m_DynamicArray.shrink_to_fit();
        }
    }
    else if (newCount > N && m_Count <= N)
    {
        // Growing, moving from m_StaticArray to m_DynamicArray
        m_DynamicArray.resize(newCount);
        if (m_Count > 0)
        {
            memcpy(m_DynamicArray.data(), m_StaticArray, m_Count * sizeof(T));
        }
    }
    else if (newCount <= N && m_Count > N)
    {
        // Shrinking, moving from m_DynamicArray to m_StaticArray
        if (newCount > 0)
        {
            memcpy(m_StaticArray, m_DynamicArray.data(), newCount * sizeof(T));
        }
        m_DynamicArray.resize(0);
        if (freeMemory)
        {
            m_DynamicArray.shrink_to_fit();
        }
    }
    else
    {
        // Any direction, staying in m_StaticArray - nothing to do here
    }
    m_Count = newCount;
}

template<typename T, typename AllocatorT, size_t N>
void VmaSmallVector<T, AllocatorT, N>::clear(bool freeMemory)
{
    m_DynamicArray.clear();
    if (freeMemory)
    {
        m_DynamicArray.shrink_to_fit();
    }
    m_Count = 0;
}

template<typename T, typename AllocatorT, size_t N>
void VmaSmallVector<T, AllocatorT, N>::insert(size_t index, const T& src)
{
    VMA_HEAVY_ASSERT(index <= m_Count);
    const size_t oldCount = size();
    resize(oldCount + 1);
    T* const dataPtr = data();
    if (index < oldCount)
    {
        //  I know, this could be more optimal for case where memmove can be memcpy directly from m_StaticArray to m_DynamicArray.
        memmove(dataPtr + (index + 1), dataPtr + index, (oldCount - index) * sizeof(T));
    }
    dataPtr[index] = src;
}

template<typename T, typename AllocatorT, size_t N>
void VmaSmallVector<T, AllocatorT, N>::remove(size_t index)
{
    VMA_HEAVY_ASSERT(index < m_Count);
    const size_t oldCount = size();
    if (index < oldCount - 1)
    {
        //  I know, this could be more optimal for case where memmove can be memcpy directly from m_DynamicArray to m_StaticArray.
        T* const dataPtr = data();
        memmove(dataPtr + index, dataPtr + (index + 1), (oldCount - index - 1) * sizeof(T));
    }
    resize(oldCount - 1);
}
#endif // _VMA_SMALL_VECTOR_FUNCTIONS
#endif // _VMA_SMALL_VECTOR

#ifndef _VMA_POOL_ALLOCATOR
/*
Allocator for objects of type T using a list of arrays (pools) to speed up
allocation. Number of elements that can be allocated is not bounded because
allocator can create multiple blocks.
*/
template<typename T>
class VmaPoolAllocator
{
    VMA_CLASS_NO_COPY(VmaPoolAllocator)
public:
    VmaPoolAllocator(const VkAllocationCallbacks* pAllocationCallbacks, uint32_t firstBlockCapacity);
    ~VmaPoolAllocator();
    template<typename... Types> T* Alloc(Types&&... args);
    void Free(T* ptr);

private:
    union Item
    {
        uint32_t NextFreeIndex;
        alignas(T) char Value[sizeof(T)];
    };
    struct ItemBlock
    {
        Item* pItems;
        uint32_t Capacity;
        uint32_t FirstFreeIndex;
    };

    const VkAllocationCallbacks* m_pAllocationCallbacks;
    const uint32_t m_FirstBlockCapacity;
    VmaVector<ItemBlock, VmaStlAllocator<ItemBlock>> m_ItemBlocks;

    ItemBlock& CreateNewBlock();
};

#ifndef _VMA_POOL_ALLOCATOR_FUNCTIONS
template<typename T>
VmaPoolAllocator<T>::VmaPoolAllocator(const VkAllocationCallbacks* pAllocationCallbacks, uint32_t firstBlockCapacity)
    : m_pAllocationCallbacks(pAllocationCallbacks),
    m_FirstBlockCapacity(firstBlockCapacity),
    m_ItemBlocks(VmaStlAllocator<ItemBlock>(pAllocationCallbacks))
{
    VMA_ASSERT(m_FirstBlockCapacity > 1);
}

template<typename T>
VmaPoolAllocator<T>::~VmaPoolAllocator()
{
    for (size_t i = m_ItemBlocks.size(); i--;)
        vma_delete_array(m_pAllocationCallbacks, m_ItemBlocks[i].pItems, m_ItemBlocks[i].Capacity);
    m_ItemBlocks.clear();
}

template<typename T>
template<typename... Types> T* VmaPoolAllocator<T>::Alloc(Types&&... args)
{
    for (size_t i = m_ItemBlocks.size(); i--; )
    {
        ItemBlock& block = m_ItemBlocks[i];
        // This block has some free items: Use first one.
        if (block.FirstFreeIndex != UINT32_MAX)
        {
            Item* const pItem = &block.pItems[block.FirstFreeIndex];
            block.FirstFreeIndex = pItem->NextFreeIndex;
            T* result = (T*)&pItem->Value;
            new(result)T(std::forward<Types>(args)...); // Explicit constructor call.
            return result;
        }
    }

    // No block has free item: Create new one and use it.
    ItemBlock& newBlock = CreateNewBlock();
    Item* const pItem = &newBlock.pItems[0];
    newBlock.FirstFreeIndex = pItem->NextFreeIndex;
    T* result = (T*)&pItem->Value;
    new(result) T(std::forward<Types>(args)...); // Explicit constructor call.
    return result;
}

template<typename T>
void VmaPoolAllocator<T>::Free(T* ptr)
{
    // Search all memory blocks to find ptr.
    for (size_t i = m_ItemBlocks.size(); i--; )
    {
        ItemBlock& block = m_ItemBlocks[i];

        // Casting to union.
        Item* pItemPtr;
        memcpy(&pItemPtr, &ptr, sizeof(pItemPtr));

        // Check if pItemPtr is in address range of this block.
        if ((pItemPtr >= block.pItems) && (pItemPtr < block.pItems + block.Capacity))
        {
            ptr->~T(); // Explicit destructor call.
            const uint32_t index = static_cast<uint32_t>(pItemPtr - block.pItems);
            pItemPtr->NextFreeIndex = block.FirstFreeIndex;
            block.FirstFreeIndex = index;
            return;
        }
    }
    VMA_ASSERT(0 && "Pointer doesn't belong to this memory pool.");
}

template<typename T>
typename VmaPoolAllocator<T>::ItemBlock& VmaPoolAllocator<T>::CreateNewBlock()
{
    const uint32_t newBlockCapacity = m_ItemBlocks.empty() ?
        m_FirstBlockCapacity : m_ItemBlocks.back().Capacity * 3 / 2;

    const ItemBlock newBlock =
    {
        vma_new_array(m_pAllocationCallbacks, Item, newBlockCapacity),
        newBlockCapacity,
        0
    };

    m_ItemBlocks.push_back(newBlock);

    // Setup singly-linked list of all free items in this block.
    for (uint32_t i = 0; i < newBlockCapacity - 1; ++i)
        newBlock.pItems[i].NextFreeIndex = i + 1;
    newBlock.pItems[newBlockCapacity - 1].NextFreeIndex = UINT32_MAX;
    return m_ItemBlocks.back();
}
#endif // _VMA_POOL_ALLOCATOR_FUNCTIONS
#endif // _VMA_POOL_ALLOCATOR

#ifndef _VMA_RAW_LIST
template<typename T>
struct VmaListItem
{
    VmaListItem* pPrev;
    VmaListItem* pNext;
    T Value;
};

// Doubly linked list.
template<typename T>
class VmaRawList
{
    VMA_CLASS_NO_COPY(VmaRawList)
public:
    typedef VmaListItem<T> ItemType;

    VmaRawList(const VkAllocationCallbacks* pAllocationCallbacks);
    // Intentionally not calling Clear, because that would be unnecessary
    // computations to return all items to m_ItemAllocator as free.
    ~VmaRawList() = default;

    size_t GetCount() const { return m_Count; }
    bool IsEmpty() const { return m_Count == 0; }

    ItemType* Front() { return m_pFront; }
    ItemType* Back() { return m_pBack; }
    const ItemType* Front() const { return m_pFront; }
    const ItemType* Back() const { return m_pBack; }

    ItemType* PushFront();
    ItemType* PushBack();
    ItemType* PushFront(const T& value);
    ItemType* PushBack(const T& value);
    void PopFront();
    void PopBack();

    // Item can be null - it means PushBack.
    ItemType* InsertBefore(ItemType* pItem);
    // Item can be null - it means PushFront.
    ItemType* InsertAfter(ItemType* pItem);
    ItemType* InsertBefore(ItemType* pItem, const T& value);
    ItemType* InsertAfter(ItemType* pItem, const T& value);

    void Clear();
    void Remove(ItemType* pItem);

private:
    const VkAllocationCallbacks* const m_pAllocationCallbacks;
    VmaPoolAllocator<ItemType> m_ItemAllocator;
    ItemType* m_pFront;
    ItemType* m_pBack;
    size_t m_Count;
};

#ifndef _VMA_RAW_LIST_FUNCTIONS
template<typename T>
VmaRawList<T>::VmaRawList(const VkAllocationCallbacks* pAllocationCallbacks)
    : m_pAllocationCallbacks(pAllocationCallbacks),
    m_ItemAllocator(pAllocationCallbacks, 128),
    m_pFront(VMA_NULL),
    m_pBack(VMA_NULL),
    m_Count(0) {}

template<typename T>
VmaListItem<T>* VmaRawList<T>::PushFront()
{
    ItemType* const pNewItem = m_ItemAllocator.Alloc();
    pNewItem->pPrev = VMA_NULL;
    if (IsEmpty())
    {
        pNewItem->pNext = VMA_NULL;
        m_pFront = pNewItem;
        m_pBack = pNewItem;
        m_Count = 1;
    }
    else
    {
        pNewItem->pNext = m_pFront;
        m_pFront->pPrev = pNewItem;
        m_pFront = pNewItem;
        ++m_Count;
    }
    return pNewItem;
}

template<typename T>
VmaListItem<T>* VmaRawList<T>::PushBack()
{
    ItemType* const pNewItem = m_ItemAllocator.Alloc();
    pNewItem->pNext = VMA_NULL;
    if(IsEmpty())
    {
        pNewItem->pPrev = VMA_NULL;
        m_pFront = pNewItem;
        m_pBack = pNewItem;
        m_Count = 1;
    }
    else
    {
        pNewItem->pPrev = m_pBack;
        m_pBack->pNext = pNewItem;
        m_pBack = pNewItem;
        ++m_Count;
    }
    return pNewItem;
}

template<typename T>
VmaListItem<T>* VmaRawList<T>::PushFront(const T& value)
{
    ItemType* const pNewItem = PushFront();
    pNewItem->Value = value;
    return pNewItem;
}

template<typename T>
VmaListItem<T>* VmaRawList<T>::PushBack(const T& value)
{
    ItemType* const pNewItem = PushBack();
    pNewItem->Value = value;
    return pNewItem;
}

template<typename T>
void VmaRawList<T>::PopFront()
{
    VMA_HEAVY_ASSERT(m_Count > 0);
    ItemType* const pFrontItem = m_pFront;
    ItemType* const pNextItem = pFrontItem->pNext;
    if (pNextItem != VMA_NULL)
    {
        pNextItem->pPrev = VMA_NULL;
    }
    m_pFront = pNextItem;
    m_ItemAllocator.Free(pFrontItem);
    --m_Count;
}

template<typename T>
void VmaRawList<T>::PopBack()
{
    VMA_HEAVY_ASSERT(m_Count > 0);
    ItemType* const pBackItem = m_pBack;
    ItemType* const pPrevItem = pBackItem->pPrev;
    if(pPrevItem != VMA_NULL)
    {
        pPrevItem->pNext = VMA_NULL;
    }
    m_pBack = pPrevItem;
    m_ItemAllocator.Free(pBackItem);
    --m_Count;
}

template<typename T>
void VmaRawList<T>::Clear()
{
    if (IsEmpty() == false)
    {
        ItemType* pItem = m_pBack;
        while (pItem != VMA_NULL)
        {
            ItemType* const pPrevItem = pItem->pPrev;
            m_ItemAllocator.Free(pItem);
            pItem = pPrevItem;
        }
        m_pFront = VMA_NULL;
        m_pBack = VMA_NULL;
        m_Count = 0;
    }
}

template<typename T>
void VmaRawList<T>::Remove(ItemType* pItem)
{
    VMA_HEAVY_ASSERT(pItem != VMA_NULL);
    VMA_HEAVY_ASSERT(m_Count > 0);

    if(pItem->pPrev != VMA_NULL)
    {
        pItem->pPrev->pNext = pItem->pNext;
    }
    else
    {
        VMA_HEAVY_ASSERT(m_pFront == pItem);
        m_pFront = pItem->pNext;
    }

    if(pItem->pNext != VMA_NULL)
    {
        pItem->pNext->pPrev = pItem->pPrev;
    }
    else
    {
        VMA_HEAVY_ASSERT(m_pBack == pItem);
        m_pBack = pItem->pPrev;
    }

    m_ItemAllocator.Free(pItem);
    --m_Count;
}

template<typename T>
VmaListItem<T>* VmaRawList<T>::InsertBefore(ItemType* pItem)
{
    if(pItem != VMA_NULL)
    {
        ItemType* const prevItem = pItem->pPrev;
        ItemType* const newItem = m_ItemAllocator.Alloc();
        newItem->pPrev = prevItem;
        newItem->pNext = pItem;
        pItem->pPrev = newItem;
        if(prevItem != VMA_NULL)
        {
            prevItem->pNext = newItem;
        }
        else
        {
            VMA_HEAVY_ASSERT(m_pFront == pItem);
            m_pFront = newItem;
        }
        ++m_Count;
        return newItem;
    }
    else
        return PushBack();
}

template<typename T>
VmaListItem<T>* VmaRawList<T>::InsertAfter(ItemType* pItem)
{
    if(pItem != VMA_NULL)
    {
        ItemType* const nextItem = pItem->pNext;
        ItemType* const newItem = m_ItemAllocator.Alloc();
        newItem->pNext = nextItem;
        newItem->pPrev = pItem;
        pItem->pNext = newItem;
        if(nextItem != VMA_NULL)
        {
            nextItem->pPrev = newItem;
        }
        else
        {
            VMA_HEAVY_ASSERT(m_pBack == pItem);
            m_pBack = newItem;
        }
        ++m_Count;
        return newItem;
    }
    else
        return PushFront();
}

template<typename T>
VmaListItem<T>* VmaRawList<T>::InsertBefore(ItemType* pItem, const T& value)
{
    ItemType* const newItem = InsertBefore(pItem);
    newItem->Value = value;
    return newItem;
}

template<typename T>
VmaListItem<T>* VmaRawList<T>::InsertAfter(ItemType* pItem, const T& value)
{
    ItemType* const newItem = InsertAfter(pItem);
    newItem->Value = value;
    return newItem;
}
#endif // _VMA_RAW_LIST_FUNCTIONS
#endif // _VMA_RAW_LIST

#ifndef _VMA_LIST
template<typename T, typename AllocatorT>
class VmaList
{
    VMA_CLASS_NO_COPY(VmaList)
public:
    class reverse_iterator;
    class const_iterator;
    class const_reverse_iterator;

    class iterator
    {
        friend class const_iterator;
        friend class VmaList<T, AllocatorT>;
    public:
        iterator() :  m_pList(VMA_NULL), m_pItem(VMA_NULL) {}
        iterator(const reverse_iterator& src) : m_pList(src.m_pList), m_pItem(src.m_pItem) {}

        T& operator*() const { VMA_HEAVY_ASSERT(m_pItem != VMA_NULL); return m_pItem->Value; }
        T* operator->() const { VMA_HEAVY_ASSERT(m_pItem != VMA_NULL); return &m_pItem->Value; }

        bool operator==(const iterator& rhs) const { VMA_HEAVY_ASSERT(m_pList == rhs.m_pList); return m_pItem == rhs.m_pItem; }
        bool operator!=(const iterator& rhs) const { VMA_HEAVY_ASSERT(m_pList == rhs.m_pList); return m_pItem != rhs.m_pItem; }

        iterator operator++(int) { iterator result = *this; ++*this; return result; }
        iterator operator--(int) { iterator result = *this; --*this; return result; }

        iterator& operator++() { VMA_HEAVY_ASSERT(m_pItem != VMA_NULL); m_pItem = m_pItem->pNext; return *this; }
        iterator& operator--();

    private:
        VmaRawList<T>* m_pList;
        VmaListItem<T>* m_pItem;

        iterator(VmaRawList<T>* pList, VmaListItem<T>* pItem) : m_pList(pList),  m_pItem(pItem) {}
    };
    class reverse_iterator
    {
        friend class const_reverse_iterator;
        friend class VmaList<T, AllocatorT>;
    public:
        reverse_iterator() : m_pList(VMA_NULL), m_pItem(VMA_NULL) {}
        reverse_iterator(const iterator& src) : m_pList(src.m_pList), m_pItem(src.m_pItem) {}

        T& operator*() const { VMA_HEAVY_ASSERT(m_pItem != VMA_NULL); return m_pItem->Value; }
        T* operator->() const { VMA_HEAVY_ASSERT(m_pItem != VMA_NULL); return &m_pItem->Value; }

        bool operator==(const reverse_iterator& rhs) const { VMA_HEAVY_ASSERT(m_pList == rhs.m_pList); return m_pItem == rhs.m_pItem; }
        bool operator!=(const reverse_iterator& rhs) const { VMA_HEAVY_ASSERT(m_pList == rhs.m_pList); return m_pItem != rhs.m_pItem; }

        reverse_iterator operator++(int) { reverse_iterator result = *this; ++* this; return result; }
        reverse_iterator operator--(int) { reverse_iterator result = *this; --* this; return result; }

        reverse_iterator& operator++() { VMA_HEAVY_ASSERT(m_pItem != VMA_NULL); m_pItem = m_pItem->pPrev; return *this; }
        reverse_iterator& operator--();

    private:
        VmaRawList<T>* m_pList;
        VmaListItem<T>* m_pItem;

        reverse_iterator(VmaRawList<T>* pList, VmaListItem<T>* pItem) : m_pList(pList),  m_pItem(pItem) {}
    };
    class const_iterator
    {
        friend class VmaList<T, AllocatorT>;
    public:
        const_iterator() : m_pList(VMA_NULL), m_pItem(VMA_NULL) {}
        const_iterator(const iterator& src) : m_pList(src.m_pList), m_pItem(src.m_pItem) {}
        const_iterator(const reverse_iterator& src) : m_pList(src.m_pList), m_pItem(src.m_pItem) {}

        iterator drop_const() { return { const_cast<VmaRawList<T>*>(m_pList), const_cast<VmaListItem<T>*>(m_pItem) }; }

        const T& operator*() const { VMA_HEAVY_ASSERT(m_pItem != VMA_NULL); return m_pItem->Value; }
        const T* operator->() const { VMA_HEAVY_ASSERT(m_pItem != VMA_NULL); return &m_pItem->Value; }

        bool operator==(const const_iterator& rhs) const { VMA_HEAVY_ASSERT(m_pList == rhs.m_pList); return m_pItem == rhs.m_pItem; }
        bool operator!=(const const_iterator& rhs) const { VMA_HEAVY_ASSERT(m_pList == rhs.m_pList); return m_pItem != rhs.m_pItem; }

        const_iterator operator++(int) { const_iterator result = *this; ++* this; return result; }
        const_iterator operator--(int) { const_iterator result = *this; --* this; return result; }

        const_iterator& operator++() { VMA_HEAVY_ASSERT(m_pItem != VMA_NULL); m_pItem = m_pItem->pNext; return *this; }
        const_iterator& operator--();

    private:
        const VmaRawList<T>* m_pList;
        const VmaListItem<T>* m_pItem;

        const_iterator(const VmaRawList<T>* pList, const VmaListItem<T>* pItem) : m_pList(pList), m_pItem(pItem) {}
    };
    class const_reverse_iterator
    {
        friend class VmaList<T, AllocatorT>;
    public:
        const_reverse_iterator() : m_pList(VMA_NULL), m_pItem(VMA_NULL) {}
        const_reverse_iterator(const reverse_iterator& src) : m_pList(src.m_pList), m_pItem(src.m_pItem) {}
        const_reverse_iterator(const iterator& src) : m_pList(src.m_pList), m_pItem(src.m_pItem) {}

        reverse_iterator drop_const() { return { const_cast<VmaRawList<T>*>(m_pList), const_cast<VmaListItem<T>*>(m_pItem) }; }

        const T& operator*() const { VMA_HEAVY_ASSERT(m_pItem != VMA_NULL); return m_pItem->Value; }
        const T* operator->() const { VMA_HEAVY_ASSERT(m_pItem != VMA_NULL); return &m_pItem->Value; }

        bool operator==(const const_reverse_iterator& rhs) const { VMA_HEAVY_ASSERT(m_pList == rhs.m_pList); return m_pItem == rhs.m_pItem; }
        bool operator!=(const const_reverse_iterator& rhs) const { VMA_HEAVY_ASSERT(m_pList == rhs.m_pList); return m_pItem != rhs.m_pItem; }

        const_reverse_iterator operator++(int) { const_reverse_iterator result = *this; ++* this; return result; }
        const_reverse_iterator operator--(int) { const_reverse_iterator result = *this; --* this; return result; }

        const_reverse_iterator& operator++() { VMA_HEAVY_ASSERT(m_pItem != VMA_NULL); m_pItem = m_pItem->pPrev; return *this; }
        const_reverse_iterator& operator--();

    private:
        const VmaRawList<T>* m_pList;
        const VmaListItem<T>* m_pItem;

        const_reverse_iterator(const VmaRawList<T>* pList, const VmaListItem<T>* pItem) : m_pList(pList), m_pItem(pItem) {}
    };

    VmaList(const AllocatorT& allocator) : m_RawList(allocator.m_pCallbacks) {}

    bool empty() const { return m_RawList.IsEmpty(); }
    size_t size() const { return m_RawList.GetCount(); }

    iterator begin() { return iterator(&m_RawList, m_RawList.Front()); }
    iterator end() { return iterator(&m_RawList, VMA_NULL); }

    const_iterator cbegin() const { return const_iterator(&m_RawList, m_RawList.Front()); }
    const_iterator cend() const { return const_iterator(&m_RawList, VMA_NULL); }

    const_iterator begin() const { return cbegin(); }
    const_iterator end() const { return cend(); }

    reverse_iterator rbegin() { return reverse_iterator(&m_RawList, m_RawList.Back()); }
    reverse_iterator rend() { return reverse_iterator(&m_RawList, VMA_NULL); }

    const_reverse_iterator crbegin() const { return const_reverse_iterator(&m_RawList, m_RawList.Back()); }
    const_reverse_iterator crend() const { return const_reverse_iterator(&m_RawList, VMA_NULL); }

    const_reverse_iterator rbegin() const { return crbegin(); }
    const_reverse_iterator rend() const { return crend(); }

    void push_back(const T& value) { m_RawList.PushBack(value); }
    iterator insert(iterator it, const T& value) { return iterator(&m_RawList, m_RawList.InsertBefore(it.m_pItem, value)); }

    void clear() { m_RawList.Clear(); }
    void erase(iterator it) { m_RawList.Remove(it.m_pItem); }

private:
    VmaRawList<T> m_RawList;
};

#ifndef _VMA_LIST_FUNCTIONS
template<typename T, typename AllocatorT>
typename VmaList<T, AllocatorT>::iterator& VmaList<T, AllocatorT>::iterator::operator--()
{
    if (m_pItem != VMA_NULL)
    {
        m_pItem = m_pItem->pPrev;
    }
    else
    {
        VMA_HEAVY_ASSERT(!m_pList->IsEmpty());
        m_pItem = m_pList->Back();
    }
    return *this;
}

template<typename T, typename AllocatorT>
typename VmaList<T, AllocatorT>::reverse_iterator& VmaList<T, AllocatorT>::reverse_iterator::operator--()
{
    if (m_pItem != VMA_NULL)
    {
        m_pItem = m_pItem->pNext;
    }
    else
    {
        VMA_HEAVY_ASSERT(!m_pList->IsEmpty());
        m_pItem = m_pList->Front();
    }
    return *this;
}

template<typename T, typename AllocatorT>
typename VmaList<T, AllocatorT>::const_iterator& VmaList<T, AllocatorT>::const_iterator::operator--()
{
    if (m_pItem != VMA_NULL)
    {
        m_pItem = m_pItem->pPrev;
    }
    else
    {
        VMA_HEAVY_ASSERT(!m_pList->IsEmpty());
        m_pItem = m_pList->Back();
    }
    return *this;
}

template<typename T, typename AllocatorT>
typename VmaList<T, AllocatorT>::const_reverse_iterator& VmaList<T, AllocatorT>::const_reverse_iterator::operator--()
{
    if (m_pItem != VMA_NULL)
    {
        m_pItem = m_pItem->pNext;
    }
    else
    {
        VMA_HEAVY_ASSERT(!m_pList->IsEmpty());
        m_pItem = m_pList->Back();
    }
    return *this;
}
#endif // _VMA_LIST_FUNCTIONS
#endif // _VMA_LIST

#ifndef _VMA_INTRUSIVE_LINKED_LIST
/*
Expected interface of ItemTypeTraits:
struct MyItemTypeTraits
{
    typedef MyItem ItemType;
    static ItemType* GetPrev(const ItemType* item) { return item->myPrevPtr; }
    static ItemType* GetNext(const ItemType* item) { return item->myNextPtr; }
    static ItemType*& AccessPrev(ItemType* item) { return item->myPrevPtr; }
    static ItemType*& AccessNext(ItemType* item) { return item->myNextPtr; }
};
*/
template<typename ItemTypeTraits>
class VmaIntrusiveLinkedList
{
public:
    typedef typename ItemTypeTraits::ItemType ItemType;
    static ItemType* GetPrev(const ItemType* item) { return ItemTypeTraits::GetPrev(item); }
    static ItemType* GetNext(const ItemType* item) { return ItemTypeTraits::GetNext(item); }

    // Movable, not copyable.
    VmaIntrusiveLinkedList() = default;
    VmaIntrusiveLinkedList(VmaIntrusiveLinkedList && src);
    VmaIntrusiveLinkedList(const VmaIntrusiveLinkedList&) = delete;
    VmaIntrusiveLinkedList& operator=(VmaIntrusiveLinkedList&& src);
    VmaIntrusiveLinkedList& operator=(const VmaIntrusiveLinkedList&) = delete;
    ~VmaIntrusiveLinkedList() { VMA_HEAVY_ASSERT(IsEmpty()); }
    
    size_t GetCount() const { return m_Count; }
    bool IsEmpty() const { return m_Count == 0; }
    ItemType* Front() { return m_Front; }
    ItemType* Back() { return m_Back; }
    const ItemType* Front() const { return m_Front; }
    const ItemType* Back() const { return m_Back; }

    void PushBack(ItemType* item);
    void PushFront(ItemType* item);
    ItemType* PopBack();
    ItemType* PopFront();

    // MyItem can be null - it means PushBack.
    void InsertBefore(ItemType* existingItem, ItemType* newItem);
    // MyItem can be null - it means PushFront.
    void InsertAfter(ItemType* existingItem, ItemType* newItem);
    void Remove(ItemType* item);
    void RemoveAll();

private:
    ItemType* m_Front = VMA_NULL;
    ItemType* m_Back = VMA_NULL;
    size_t m_Count = 0;
};

#ifndef _VMA_INTRUSIVE_LINKED_LIST_FUNCTIONS
template<typename ItemTypeTraits>
VmaIntrusiveLinkedList<ItemTypeTraits>::VmaIntrusiveLinkedList(VmaIntrusiveLinkedList&& src)
    : m_Front(src.m_Front), m_Back(src.m_Back), m_Count(src.m_Count)
{
    src.m_Front = src.m_Back = VMA_NULL;
    src.m_Count = 0;
}

template<typename ItemTypeTraits>
VmaIntrusiveLinkedList<ItemTypeTraits>& VmaIntrusiveLinkedList<ItemTypeTraits>::operator=(VmaIntrusiveLinkedList&& src)
{
    if (&src != this)
    {
        VMA_HEAVY_ASSERT(IsEmpty());
        m_Front = src.m_Front;
        m_Back = src.m_Back;
        m_Count = src.m_Count;
        src.m_Front = src.m_Back = VMA_NULL;
        src.m_Count = 0;
    }
    return *this;
}

template<typename ItemTypeTraits>
void VmaIntrusiveLinkedList<ItemTypeTraits>::PushBack(ItemType* item)
{
    VMA_HEAVY_ASSERT(ItemTypeTraits::GetPrev(item) == VMA_NULL && ItemTypeTraits::GetNext(item) == VMA_NULL);
    if (IsEmpty())
    {
        m_Front = item;
        m_Back = item;
        m_Count = 1;
    }
    else
    {
        ItemTypeTraits::AccessPrev(item) = m_Back;
        ItemTypeTraits::AccessNext(m_Back) = item;
        m_Back = item;
        ++m_Count;
    }
}

template<typename ItemTypeTraits>
void VmaIntrusiveLinkedList<ItemTypeTraits>::PushFront(ItemType* item)
{
    VMA_HEAVY_ASSERT(ItemTypeTraits::GetPrev(item) == VMA_NULL && ItemTypeTraits::GetNext(item) == VMA_NULL);
    if (IsEmpty())
    {
        m_Front = item;
        m_Back = item;
        m_Count = 1;
    }
    else
    {
        ItemTypeTraits::AccessNext(item) = m_Front;
        ItemTypeTraits::AccessPrev(m_Front) = item;
        m_Front = item;
        ++m_Count;
    }
}

template<typename ItemTypeTraits>
typename VmaIntrusiveLinkedList<ItemTypeTraits>::ItemType* VmaIntrusiveLinkedList<ItemTypeTraits>::PopBack()
{
    VMA_HEAVY_ASSERT(m_Count > 0);
    ItemType* const backItem = m_Back;
    ItemType* const prevItem = ItemTypeTraits::GetPrev(backItem);
    if (prevItem != VMA_NULL)
    {
        ItemTypeTraits::AccessNext(prevItem) = VMA_NULL;
    }
    m_Back = prevItem;
    --m_Count;
    ItemTypeTraits::AccessPrev(backItem) = VMA_NULL;
    ItemTypeTraits::AccessNext(backItem) = VMA_NULL;
    return backItem;
}

template<typename ItemTypeTraits>
typename VmaIntrusiveLinkedList<ItemTypeTraits>::ItemType* VmaIntrusiveLinkedList<ItemTypeTraits>::PopFront()
{
    VMA_HEAVY_ASSERT(m_Count > 0);
    ItemType* const frontItem = m_Front;
    ItemType* const nextItem = ItemTypeTraits::GetNext(frontItem);
    if (nextItem != VMA_NULL)
    {
        ItemTypeTraits::AccessPrev(nextItem) = VMA_NULL;
    }
    m_Front = nextItem;
    --m_Count;
    ItemTypeTraits::AccessPrev(frontItem) = VMA_NULL;
    ItemTypeTraits::AccessNext(frontItem) = VMA_NULL;
    return frontItem;
}

template<typename ItemTypeTraits>
void VmaIntrusiveLinkedList<ItemTypeTraits>::InsertBefore(ItemType* existingItem, ItemType* newItem)
{
    VMA_HEAVY_ASSERT(newItem != VMA_NULL && ItemTypeTraits::GetPrev(newItem) == VMA_NULL && ItemTypeTraits::GetNext(newItem) == VMA_NULL);
    if (existingItem != VMA_NULL)
    {
        ItemType* const prevItem = ItemTypeTraits::GetPrev(existingItem);
        ItemTypeTraits::AccessPrev(newItem) = prevItem;
        ItemTypeTraits::AccessNext(newItem) = existingItem;
        ItemTypeTraits::AccessPrev(existingItem) = newItem;
        if (prevItem != VMA_NULL)
        {
            ItemTypeTraits::AccessNext(prevItem) = newItem;
        }
        else
        {
            VMA_HEAVY_ASSERT(m_Front == existingItem);
            m_Front = newItem;
        }
        ++m_Count;
    }
    else
        PushBack(newItem);
}

template<typename ItemTypeTraits>
void VmaIntrusiveLinkedList<ItemTypeTraits>::InsertAfter(ItemType* existingItem, ItemType* newItem)
{
    VMA_HEAVY_ASSERT(newItem != VMA_NULL && ItemTypeTraits::GetPrev(newItem) == VMA_NULL && ItemTypeTraits::GetNext(newItem) == VMA_NULL);
    if (existingItem != VMA_NULL)
    {
        ItemType* const nextItem = ItemTypeTraits::GetNext(existingItem);
        ItemTypeTraits::AccessNext(newItem) = nextItem;
        ItemTypeTraits::AccessPrev(newItem) = existingItem;
        ItemTypeTraits::AccessNext(existingItem) = newItem;
        if (nextItem != VMA_NULL)
        {
            ItemTypeTraits::AccessPrev(nextItem) = newItem;
        }
        else
        {
            VMA_HEAVY_ASSERT(m_Back == existingItem);
            m_Back = newItem;
        }
        ++m_Count;
    }
    else
        return PushFront(newItem);
}

template<typename ItemTypeTraits>
void VmaIntrusiveLinkedList<ItemTypeTraits>::Remove(ItemType* item)
{
    VMA_HEAVY_ASSERT(item != VMA_NULL && m_Count > 0);
    if (ItemTypeTraits::GetPrev(item) != VMA_NULL)
    {
        ItemTypeTraits::AccessNext(ItemTypeTraits::AccessPrev(item)) = ItemTypeTraits::GetNext(item);
    }
    else
    {
        VMA_HEAVY_ASSERT(m_Front == item);
        m_Front = ItemTypeTraits::GetNext(item);
    }

    if (ItemTypeTraits::GetNext(item) != VMA_NULL)
    {
        ItemTypeTraits::AccessPrev(ItemTypeTraits::AccessNext(item)) = ItemTypeTraits::GetPrev(item);
    }
    else
    {
        VMA_HEAVY_ASSERT(m_Back == item);
        m_Back = ItemTypeTraits::GetPrev(item);
    }
    ItemTypeTraits::AccessPrev(item) = VMA_NULL;
    ItemTypeTraits::AccessNext(item) = VMA_NULL;
    --m_Count;
}

template<typename ItemTypeTraits>
void VmaIntrusiveLinkedList<ItemTypeTraits>::RemoveAll()
{
    if (!IsEmpty())
    {
        ItemType* item = m_Back;
        while (item != VMA_NULL)
        {
            ItemType* const prevItem = ItemTypeTraits::AccessPrev(item);
            ItemTypeTraits::AccessPrev(item) = VMA_NULL;
            ItemTypeTraits::AccessNext(item) = VMA_NULL;
            item = prevItem;
        }
        m_Front = VMA_NULL;
        m_Back = VMA_NULL;
        m_Count = 0;
    }
}
#endif // _VMA_INTRUSIVE_LINKED_LIST_FUNCTIONS
#endif // _VMA_INTRUSIVE_LINKED_LIST

// Unused in this version.
#if 0

#ifndef _VMA_PAIR
template<typename T1, typename T2>
struct VmaPair
{
    T1 first;
    T2 second;

    VmaPair() : first(), second() {}
    VmaPair(const T1& firstSrc, const T2& secondSrc) : first(firstSrc), second(secondSrc) {}
};

template<typename FirstT, typename SecondT>
struct VmaPairFirstLess
{
    bool operator()(const VmaPair<FirstT, SecondT>& lhs, const VmaPair<FirstT, SecondT>& rhs) const
    {
        return lhs.first < rhs.first;
    }
    bool operator()(const VmaPair<FirstT, SecondT>& lhs, const FirstT& rhsFirst) const
    {
        return lhs.first < rhsFirst;
    }
};
#endif // _VMA_PAIR

#ifndef _VMA_MAP
/* Class compatible with subset of interface of std::unordered_map.
KeyT, ValueT must be POD because they will be stored in VmaVector.
*/
template<typename KeyT, typename ValueT>
class VmaMap
{
public:
    typedef VmaPair<KeyT, ValueT> PairType;
    typedef PairType* iterator;

    VmaMap(const VmaStlAllocator<PairType>& allocator) : m_Vector(allocator) {}

    iterator begin() { return m_Vector.begin(); }
    iterator end() { return m_Vector.end(); }
    size_t size() { return m_Vector.size(); }

    void insert(const PairType& pair);
    iterator find(const KeyT& key);
    void erase(iterator it);

private:
    VmaVector< PairType, VmaStlAllocator<PairType>> m_Vector;
};

#ifndef _VMA_MAP_FUNCTIONS
template<typename KeyT, typename ValueT>
void VmaMap<KeyT, ValueT>::insert(const PairType& pair)
{
    const size_t indexToInsert = VmaBinaryFindFirstNotLess(
        m_Vector.data(),
        m_Vector.data() + m_Vector.size(),
        pair,
        VmaPairFirstLess<KeyT, ValueT>()) - m_Vector.data();
    VmaVectorInsert(m_Vector, indexToInsert, pair);
}

template<typename KeyT, typename ValueT>
VmaPair<KeyT, ValueT>* VmaMap<KeyT, ValueT>::find(const KeyT& key)
{
    PairType* it = VmaBinaryFindFirstNotLess(
        m_Vector.data(),
        m_Vector.data() + m_Vector.size(),
        key,
        VmaPairFirstLess<KeyT, ValueT>());
    if ((it != m_Vector.end()) && (it->first == key))
    {
        return it;
    }
    else
    {
        return m_Vector.end();
    }
}

template<typename KeyT, typename ValueT>
void VmaMap<KeyT, ValueT>::erase(iterator it)
{
    VmaVectorRemove(m_Vector, it - m_Vector.begin());
}
#endif // _VMA_MAP_FUNCTIONS
#endif // _VMA_MAP

#endif // #if 0

#if !defined(_VMA_STRING_BUILDER) && VMA_STATS_STRING_ENABLED
class VmaStringBuilder
{
public:
    VmaStringBuilder(const VkAllocationCallbacks* allocationCallbacks) : m_Data(VmaStlAllocator<char>(allocationCallbacks)) {}
    ~VmaStringBuilder() = default;

    size_t GetLength() const { return m_Data.size(); }
    const char* GetData() const { return m_Data.data(); }
    void AddNewLine() { Add('\n'); }
    void Add(char ch) { m_Data.push_back(ch); }

    void Add(const char* pStr);
    void AddNumber(uint32_t num);
    void AddNumber(uint64_t num);
    void AddPointer(const void* ptr);

private:
    VmaVector<char, VmaStlAllocator<char>> m_Data;
};

#ifndef _VMA_STRING_BUILDER_FUNCTIONS
void VmaStringBuilder::Add(const char* pStr)
{
    const size_t strLen = strlen(pStr);
    if (strLen > 0)
    {
        const size_t oldCount = m_Data.size();
        m_Data.resize(oldCount + strLen);
        memcpy(m_Data.data() + oldCount, pStr, strLen);
    }
}

void VmaStringBuilder::AddNumber(uint32_t num)
{
    char buf[11];
    buf[10] = '\0';
    char* p = &buf[10];
    do
    {
        *--p = '0' + (num % 10);
        num /= 10;
    } while (num);
    Add(p);
}

void VmaStringBuilder::AddNumber(uint64_t num)
{
    char buf[21];
    buf[20] = '\0';
    char* p = &buf[20];
    do
    {
        *--p = '0' + (num % 10);
        num /= 10;
    } while (num);
    Add(p);
}

void VmaStringBuilder::AddPointer(const void* ptr)
{
    char buf[21];
    VmaPtrToStr(buf, sizeof(buf), ptr);
    Add(buf);
}
#endif //_VMA_STRING_BUILDER_FUNCTIONS
#endif // _VMA_STRING_BUILDER

#if !defined(_VMA_JSON_WRITER) && VMA_STATS_STRING_ENABLED
/*
Allows to conveniently build a correct JSON document to be written to the
VmaStringBuilder passed to the constructor.
*/
class VmaJsonWriter
{
    VMA_CLASS_NO_COPY(VmaJsonWriter)
public:
    // sb - string builder to write the document to. Must remain alive for the whole lifetime of this object.
    VmaJsonWriter(const VkAllocationCallbacks* pAllocationCallbacks, VmaStringBuilder& sb);
    ~VmaJsonWriter();

    // Begins object by writing "{".
    // Inside an object, you must call pairs of WriteString and a value, e.g.:
    // j.BeginObject(true); j.WriteString("A"); j.WriteNumber(1); j.WriteString("B"); j.WriteNumber(2); j.EndObject();
    // Will write: { "A": 1, "B": 2 }
    void BeginObject(bool singleLine = false);
    // Ends object by writing "}".
    void EndObject();

    // Begins array by writing "[".
    // Inside an array, you can write a sequence of any values.
    void BeginArray(bool singleLine = false);
    // Ends array by writing "[".
    void EndArray();

    // Writes a string value inside "".
    // pStr can contain any ANSI characters, including '"', new line etc. - they will be properly escaped.
    void WriteString(const char* pStr);
    
    // Begins writing a string value.
    // Call BeginString, ContinueString, ContinueString, ..., EndString instead of
    // WriteString to conveniently build the string content incrementally, made of
    // parts including numbers.
    void BeginString(const char* pStr = VMA_NULL);
    // Posts next part of an open string.
    void ContinueString(const char* pStr);
    // Posts next part of an open string. The number is converted to decimal characters.
    void ContinueString(uint32_t n);
    void ContinueString(uint64_t n);
    void ContinueString_Size(size_t n);
    // Posts next part of an open string. Pointer value is converted to characters
    // using "%p" formatting - shown as hexadecimal number, e.g.: 000000081276Ad00
    void ContinueString_Pointer(const void* ptr);
    // Ends writing a string value by writing '"'.
    void EndString(const char* pStr = VMA_NULL);

    // Writes a number value.
    void WriteNumber(uint32_t n);
    void WriteNumber(uint64_t n);
    void WriteSize(size_t n);
    // Writes a boolean value - false or true.
    void WriteBool(bool b);
    // Writes a null value.
    void WriteNull();

private:
    enum COLLECTION_TYPE
    {
        COLLECTION_TYPE_OBJECT,
        COLLECTION_TYPE_ARRAY,
    };
    struct StackItem
    {
        COLLECTION_TYPE type;
        uint32_t valueCount;
        bool singleLineMode;
    };

    static const char* const INDENT;

    VmaStringBuilder& m_SB;
    VmaVector< StackItem, VmaStlAllocator<StackItem> > m_Stack;
    bool m_InsideString;

    // Write size_t for less than 64bits
    void WriteSize(size_t n, std::integral_constant<bool, false>) { m_SB.AddNumber(static_cast<uint32_t>(n)); }
    // Write size_t for 64bits
    void WriteSize(size_t n, std::integral_constant<bool, true>) { m_SB.AddNumber(static_cast<uint64_t>(n)); }

    void BeginValue(bool isString);
    void WriteIndent(bool oneLess = false);
};
const char* const VmaJsonWriter::INDENT = "  ";

#ifndef _VMA_JSON_WRITER_FUNCTIONS
VmaJsonWriter::VmaJsonWriter(const VkAllocationCallbacks* pAllocationCallbacks, VmaStringBuilder& sb)
    : m_SB(sb),
    m_Stack(VmaStlAllocator<StackItem>(pAllocationCallbacks)),
    m_InsideString(false) {}

VmaJsonWriter::~VmaJsonWriter()
{
    VMA_ASSERT(!m_InsideString);
    VMA_ASSERT(m_Stack.empty());
}

void VmaJsonWriter::BeginObject(bool singleLine)
{
    VMA_ASSERT(!m_InsideString);

    BeginValue(false);
    m_SB.Add('{');

    StackItem item;
    item.type = COLLECTION_TYPE_OBJECT;
    item.valueCount = 0;
    item.singleLineMode = singleLine;
    m_Stack.push_back(item);
}

void VmaJsonWriter::EndObject()
{
    VMA_ASSERT(!m_InsideString);

    WriteIndent(true);
    m_SB.Add('}');

    VMA_ASSERT(!m_Stack.empty() && m_Stack.back().type == COLLECTION_TYPE_OBJECT);
    m_Stack.pop_back();
}

void VmaJsonWriter::BeginArray(bool singleLine)
{
    VMA_ASSERT(!m_InsideString);

    BeginValue(false);
    m_SB.Add('[');

    StackItem item;
    item.type = COLLECTION_TYPE_ARRAY;
    item.valueCount = 0;
    item.singleLineMode = singleLine;
    m_Stack.push_back(item);
}

void VmaJsonWriter::EndArray()
{
    VMA_ASSERT(!m_InsideString);

    WriteIndent(true);
    m_SB.Add(']');

    VMA_ASSERT(!m_Stack.empty() && m_Stack.back().type == COLLECTION_TYPE_ARRAY);
    m_Stack.pop_back();
}

void VmaJsonWriter::WriteString(const char* pStr)
{
    BeginString(pStr);
    EndString();
}

void VmaJsonWriter::BeginString(const char* pStr)
{
    VMA_ASSERT(!m_InsideString);

    BeginValue(true);
    m_SB.Add('"');
    m_InsideString = true;
    if (pStr != VMA_NULL && pStr[0] != '\0')
    {
        ContinueString(pStr);
    }
}

void VmaJsonWriter::ContinueString(const char* pStr)
{
    VMA_ASSERT(m_InsideString);

    const size_t strLen = strlen(pStr);
    for (size_t i = 0; i < strLen; ++i)
    {
        char ch = pStr[i];
        if (ch == '\\')
        {
            m_SB.Add("\\\\");
        }
        else if (ch == '"')
        {
            m_SB.Add("\\\"");
        }
        else if (ch >= 32)
        {
            m_SB.Add(ch);
        }
        else switch (ch)
        {
        case '\b':
            m_SB.Add("\\b");
            break;
        case '\f':
            m_SB.Add("\\f");
            break;
        case '\n':
            m_SB.Add("\\n");
            break;
        case '\r':
            m_SB.Add("\\r");
            break;
        case '\t':
            m_SB.Add("\\t");
            break;
        default:
            VMA_ASSERT(0 && "Character not currently supported.");
            break;
        }
    }
}

void VmaJsonWriter::ContinueString(uint32_t n)
{
    VMA_ASSERT(m_InsideString);
    m_SB.AddNumber(n);
}

void VmaJsonWriter::ContinueString(uint64_t n)
{
    VMA_ASSERT(m_InsideString);
    m_SB.AddNumber(n);
}

void VmaJsonWriter::ContinueString_Size(size_t n)
{
    VMA_ASSERT(m_InsideString);
    // Fix for AppleClang incorrect type casting
    // TODO: Change to if constexpr when C++17 used as minimal standard
    WriteSize(n, std::is_same<size_t, uint64_t>{});
}

void VmaJsonWriter::ContinueString_Pointer(const void* ptr)
{
    VMA_ASSERT(m_InsideString);
    m_SB.AddPointer(ptr);
}

void VmaJsonWriter::EndString(const char* pStr)
{
    VMA_ASSERT(m_InsideString);
    if (pStr != VMA_NULL && pStr[0] != '\0')
    {
        ContinueString(pStr);
    }
    m_SB.Add('"');
    m_InsideString = false;
}

void VmaJsonWriter::WriteNumber(uint32_t n)
{
    VMA_ASSERT(!m_InsideString);
    BeginValue(false);
    m_SB.AddNumber(n);
}

void VmaJsonWriter::WriteNumber(uint64_t n)
{
    VMA_ASSERT(!m_InsideString);
    BeginValue(false);
    m_SB.AddNumber(n);
}

void VmaJsonWriter::WriteSize(size_t n)
{
    VMA_ASSERT(!m_InsideString);
    BeginValue(false);
    // Fix for AppleClang incorrect type casting
    // TODO: Change to if constexpr when C++17 used as minimal standard
    WriteSize(n, std::is_same<size_t, uint64_t>{});
}

void VmaJsonWriter::WriteBool(bool b)
{
    VMA_ASSERT(!m_InsideString);
    BeginValue(false);
    m_SB.Add(b ? "true" : "false");
}

void VmaJsonWriter::WriteNull()
{
    VMA_ASSERT(!m_InsideString);
    BeginValue(false);
    m_SB.Add("null");
}

void VmaJsonWriter::BeginValue(bool isString)
{
    if (!m_Stack.empty())
    {
        StackItem& currItem = m_Stack.back();
        if (currItem.type == COLLECTION_TYPE_OBJECT &&
            currItem.valueCount % 2 == 0)
        {
            VMA_ASSERT(isString);
        }

        if (currItem.type == COLLECTION_TYPE_OBJECT &&
            currItem.valueCount % 2 != 0)
        {
            m_SB.Add(": ");
        }
        else if (currItem.valueCount > 0)
        {
            m_SB.Add(", ");
            WriteIndent();
        }
        else
        {
            WriteIndent();
        }
        ++currItem.valueCount;
    }
}

void VmaJsonWriter::WriteIndent(bool oneLess)
{
    if (!m_Stack.empty() && !m_Stack.back().singleLineMode)
    {
        m_SB.AddNewLine();

        size_t count = m_Stack.size();
        if (count > 0 && oneLess)
        {
            --count;
        }
        for (size_t i = 0; i < count; ++i)
        {
            m_SB.Add(INDENT);
        }
    }
}
#endif // _VMA_JSON_WRITER_FUNCTIONS

static void VmaPrintDetailedStatistics(VmaJsonWriter& json, const VmaDetailedStatistics& stat)
{
    json.BeginObject();

    json.WriteString("BlockCount");
    json.WriteNumber(stat.statistics.blockCount);
    json.WriteString("BlockBytes");
    json.WriteNumber(stat.statistics.blockBytes);
    json.WriteString("AllocationCount");
    json.WriteNumber(stat.statistics.allocationCount);
    json.WriteString("AllocationBytes");
    json.WriteNumber(stat.statistics.allocationBytes);
    json.WriteString("UnusedRangeCount");
    json.WriteNumber(stat.unusedRangeCount);

    if (stat.statistics.allocationCount > 1)
    {
        json.WriteString("AllocationSizeMin");
        json.WriteNumber(stat.allocationSizeMin);
        json.WriteString("AllocationSizeMax");
        json.WriteNumber(stat.allocationSizeMax);
    }
    if (stat.unusedRangeCount > 1)
    {
        json.WriteString("UnusedRangeSizeMin");
        json.WriteNumber(stat.unusedRangeSizeMin);
        json.WriteString("UnusedRangeSizeMax");
        json.WriteNumber(stat.unusedRangeSizeMax);
    }
    json.EndObject();
}
#endif // _VMA_JSON_WRITER

#ifndef _VMA_MAPPING_HYSTERESIS

class VmaMappingHysteresis
{
    VMA_CLASS_NO_COPY(VmaMappingHysteresis)
public:
    VmaMappingHysteresis() = default;

    uint32_t GetExtraMapping() const { return m_ExtraMapping; }

    // Call when Map was called.
    // Returns true if switched to extra +1 mapping reference count.
    bool PostMap()
    {
#if VMA_MAPPING_HYSTERESIS_ENABLED
        if(m_ExtraMapping == 0)
        {
            ++m_MajorCounter;
            if(m_MajorCounter >= COUNTER_MIN_EXTRA_MAPPING)
            {
                m_ExtraMapping = 1;
                m_MajorCounter = 0;
                m_MinorCounter = 0;
                return true;
            }
        }
        else // m_ExtraMapping == 1
            PostMinorCounter();
#endif // #if VMA_MAPPING_HYSTERESIS_ENABLED
        return false;
    }

    // Call when Unmap was called.
    void PostUnmap()
    {
#if VMA_MAPPING_HYSTERESIS_ENABLED
        if(m_ExtraMapping == 0)
            ++m_MajorCounter;
        else // m_ExtraMapping == 1
            PostMinorCounter();
#endif // #if VMA_MAPPING_HYSTERESIS_ENABLED
    }

    // Call when allocation was made from the memory block.
    void PostAlloc()
    {
#if VMA_MAPPING_HYSTERESIS_ENABLED
        if(m_ExtraMapping == 1)
            ++m_MajorCounter;
        else // m_ExtraMapping == 0
            PostMinorCounter();
#endif // #if VMA_MAPPING_HYSTERESIS_ENABLED
    }

    // Call when allocation was freed from the memory block.
    // Returns true if switched to extra -1 mapping reference count.
    bool PostFree()
    {
#if VMA_MAPPING_HYSTERESIS_ENABLED
        if(m_ExtraMapping == 1)
        {
            ++m_MajorCounter;
            if(m_MajorCounter >= COUNTER_MIN_EXTRA_MAPPING &&
                m_MajorCounter > m_MinorCounter + 1)
            {
                m_ExtraMapping = 0;
                m_MajorCounter = 0;
                m_MinorCounter = 0;
                return true;
            }
        }
        else // m_ExtraMapping == 0
            PostMinorCounter();
#endif // #if VMA_MAPPING_HYSTERESIS_ENABLED
        return false;
    }

private:
    static const int32_t COUNTER_MIN_EXTRA_MAPPING = 7;

    uint32_t m_MinorCounter = 0;
    uint32_t m_MajorCounter = 0;
    uint32_t m_ExtraMapping = 0; // 0 or 1.

    void PostMinorCounter()
    {
        if(m_MinorCounter < m_MajorCounter)
        {
            ++m_MinorCounter;
        }
        else if(m_MajorCounter > 0)
        {
            --m_MajorCounter;
            --m_MinorCounter;
        }
    }
};

#endif // _VMA_MAPPING_HYSTERESIS

#ifndef _VMA_DEVICE_MEMORY_BLOCK
/*
Represents a single block of device memory (`VkDeviceMemory`) with all the
data about its regions (aka suballocations, #VmaAllocation), assigned and free.

Thread-safety:
- Access to m_pMetadata must be externally synchronized.
- Map, Unmap, Bind* are synchronized internally.
*/
class VmaDeviceMemoryBlock
{
    VMA_CLASS_NO_COPY(VmaDeviceMemoryBlock)
public:
    VmaBlockMetadata* m_pMetadata;

    VmaDeviceMemoryBlock(VmaAllocator hAllocator);
    ~VmaDeviceMemoryBlock();

    // Always call after construction.
    void Init(
        VmaAllocator hAllocator,
        VmaPool hParentPool,
        uint32_t newMemoryTypeIndex,
        VkDeviceMemory newMemory,
        VkDeviceSize newSize,
        uint32_t id,
        uint32_t algorithm,
        VkDeviceSize bufferImageGranularity);
    // Always call before destruction.
    void Destroy(VmaAllocator allocator);

    VmaPool GetParentPool() const { return m_hParentPool; }
    VkDeviceMemory GetDeviceMemory() const { return m_hMemory; }
    uint32_t GetMemoryTypeIndex() const { return m_MemoryTypeIndex; }
    uint32_t GetId() const { return m_Id; }
    void* GetMappedData() const { return m_pMappedData; }
    uint32_t GetMapRefCount() const { return m_MapCount; }

    // Call when allocation/free was made from m_pMetadata.
    // Used for m_MappingHysteresis.
    void PostAlloc() { m_MappingHysteresis.PostAlloc(); }
    void PostFree(VmaAllocator hAllocator);

    // Validates all data structures inside this object. If not valid, returns false.
    bool Validate() const;
    VkResult CheckCorruption(VmaAllocator hAllocator);

    // ppData can be null.
    VkResult Map(VmaAllocator hAllocator, uint32_t count, void** ppData);
    void Unmap(VmaAllocator hAllocator, uint32_t count);

    VkResult WriteMagicValueAfterAllocation(VmaAllocator hAllocator, VkDeviceSize allocOffset, VkDeviceSize allocSize);
    VkResult ValidateMagicValueAfterAllocation(VmaAllocator hAllocator, VkDeviceSize allocOffset, VkDeviceSize allocSize);

    VkResult BindBufferMemory(
        const VmaAllocator hAllocator,
        const VmaAllocation hAllocation,
        VkDeviceSize allocationLocalOffset,
        VkBuffer hBuffer,
        const void* pNext);
    VkResult BindImageMemory(
        const VmaAllocator hAllocator,
        const VmaAllocation hAllocation,
        VkDeviceSize allocationLocalOffset,
        VkImage hImage,
        const void* pNext);

private:
    VmaPool m_hParentPool; // VK_NULL_HANDLE if not belongs to custom pool.
    uint32_t m_MemoryTypeIndex;
    uint32_t m_Id;
    VkDeviceMemory m_hMemory;

    /*
    Protects access to m_hMemory so it is not used by multiple threads simultaneously, e.g. vkMapMemory, vkBindBufferMemory.
    Also protects m_MapCount, m_pMappedData.
    Allocations, deallocations, any change in m_pMetadata is protected by parent's VmaBlockVector::m_Mutex.
    */
    VMA_MUTEX m_MapAndBindMutex;
    VmaMappingHysteresis m_MappingHysteresis;
    uint32_t m_MapCount;
    void* m_pMappedData;
};
#endif // _VMA_DEVICE_MEMORY_BLOCK

#ifndef _VMA_ALLOCATION_T
struct VmaAllocation_T
{
    friend struct VmaDedicatedAllocationListItemTraits;

    enum FLAGS
    {
        FLAG_PERSISTENT_MAP   = 0x01,
        FLAG_MAPPING_ALLOWED  = 0x02,
    };

public:
    enum ALLOCATION_TYPE
    {
        ALLOCATION_TYPE_NONE,
        ALLOCATION_TYPE_BLOCK,
        ALLOCATION_TYPE_DEDICATED,
    };

    // This struct is allocated using VmaPoolAllocator.
    VmaAllocation_T(bool mappingAllowed);
    ~VmaAllocation_T();

    void InitBlockAllocation(
        VmaDeviceMemoryBlock* block,
        VmaAllocHandle allocHandle,
        VkDeviceSize alignment,
        VkDeviceSize size,
        uint32_t memoryTypeIndex,
        VmaSuballocationType suballocationType,
        bool mapped);
    // pMappedData not null means allocation is created with MAPPED flag.
    void InitDedicatedAllocation(
        VmaPool hParentPool,
        uint32_t memoryTypeIndex,
        VkDeviceMemory hMemory,
        VmaSuballocationType suballocationType,
        void* pMappedData,
        VkDeviceSize size);

    ALLOCATION_TYPE GetType() const { return (ALLOCATION_TYPE)m_Type; }
    VkDeviceSize GetAlignment() const { return m_Alignment; }
    VkDeviceSize GetSize() const { return m_Size; }
    void* GetUserData() const { return m_pUserData; }
    const char* GetName() const { return m_pName; }
    VmaSuballocationType GetSuballocationType() const { return (VmaSuballocationType)m_SuballocationType; }

    VmaDeviceMemoryBlock* GetBlock() const { VMA_ASSERT(m_Type == ALLOCATION_TYPE_BLOCK); return m_BlockAllocation.m_Block; }
    uint32_t GetMemoryTypeIndex() const { return m_MemoryTypeIndex; }
    bool IsPersistentMap() const { return (m_Flags & FLAG_PERSISTENT_MAP) != 0; }
    bool IsMappingAllowed() const { return (m_Flags & FLAG_MAPPING_ALLOWED) != 0; }

    void SetUserData(VmaAllocator hAllocator, void* pUserData) { m_pUserData = pUserData; }
    void SetName(VmaAllocator hAllocator, const char* pName);
    void FreeName(VmaAllocator hAllocator);
    uint8_t SwapBlockAllocation(VmaAllocator hAllocator, VmaAllocation allocation);
    VmaAllocHandle GetAllocHandle() const;
    VkDeviceSize GetOffset() const;
    VmaPool GetParentPool() const;
    VkDeviceMemory GetMemory() const;
    void* GetMappedData() const;

    void BlockAllocMap();
    void BlockAllocUnmap();
    VkResult DedicatedAllocMap(VmaAllocator hAllocator, void** ppData);
    void DedicatedAllocUnmap(VmaAllocator hAllocator);

#if VMA_STATS_STRING_ENABLED
    uint32_t GetBufferImageUsage() const { return m_BufferImageUsage; }

    void InitBufferImageUsage(uint32_t bufferImageUsage);
    void PrintParameters(class VmaJsonWriter& json) const;
#endif

private:
    // Allocation out of VmaDeviceMemoryBlock.
    struct BlockAllocation
    {
        VmaDeviceMemoryBlock* m_Block;
        VmaAllocHandle m_AllocHandle;
    };
    // Allocation for an object that has its own private VkDeviceMemory.
    struct DedicatedAllocation
    {
        VmaPool m_hParentPool; // VK_NULL_HANDLE if not belongs to custom pool.
        VkDeviceMemory m_hMemory;
        void* m_pMappedData; // Not null means memory is mapped.
        VmaAllocation_T* m_Prev;
        VmaAllocation_T* m_Next;
    };
    union
    {
        // Allocation out of VmaDeviceMemoryBlock.
        BlockAllocation m_BlockAllocation;
        // Allocation for an object that has its own private VkDeviceMemory.
        DedicatedAllocation m_DedicatedAllocation;
    };

    VkDeviceSize m_Alignment;
    VkDeviceSize m_Size;
    void* m_pUserData;
    char* m_pName;
    uint32_t m_MemoryTypeIndex;
    uint8_t m_Type; // ALLOCATION_TYPE
    uint8_t m_SuballocationType; // VmaSuballocationType
    // Reference counter for vmaMapMemory()/vmaUnmapMemory().
    uint8_t m_MapCount;
    uint8_t m_Flags; // enum FLAGS
#if VMA_STATS_STRING_ENABLED
    uint32_t m_BufferImageUsage; // 0 if unknown.
#endif
};
#endif // _VMA_ALLOCATION_T

#ifndef _VMA_DEDICATED_ALLOCATION_LIST_ITEM_TRAITS
struct VmaDedicatedAllocationListItemTraits
{
    typedef VmaAllocation_T ItemType;

    static ItemType* GetPrev(const ItemType* item)
    {
        VMA_HEAVY_ASSERT(item->GetType() == VmaAllocation_T::ALLOCATION_TYPE_DEDICATED);
        return item->m_DedicatedAllocation.m_Prev;
    }
    static ItemType* GetNext(const ItemType* item)
    {
        VMA_HEAVY_ASSERT(item->GetType() == VmaAllocation_T::ALLOCATION_TYPE_DEDICATED);
        return item->m_DedicatedAllocation.m_Next;
    }
    static ItemType*& AccessPrev(ItemType* item)
    {
        VMA_HEAVY_ASSERT(item->GetType() == VmaAllocation_T::ALLOCATION_TYPE_DEDICATED);
        return item->m_DedicatedAllocation.m_Prev;
    }
    static ItemType*& AccessNext(ItemType* item)
    {
        VMA_HEAVY_ASSERT(item->GetType() == VmaAllocation_T::ALLOCATION_TYPE_DEDICATED);
        return item->m_DedicatedAllocation.m_Next;
    }
};
#endif // _VMA_DEDICATED_ALLOCATION_LIST_ITEM_TRAITS

#ifndef _VMA_DEDICATED_ALLOCATION_LIST
/*
Stores linked list of VmaAllocation_T objects.
Thread-safe, synchronized internally.
*/
class VmaDedicatedAllocationList
{
public:
    VmaDedicatedAllocationList() {}
    ~VmaDedicatedAllocationList();

    void Init(bool useMutex) { m_UseMutex = useMutex; }
    bool Validate();

    void AddDetailedStatistics(VmaDetailedStatistics& inoutStats);
    void AddStatistics(VmaStatistics& inoutStats);
#if VMA_STATS_STRING_ENABLED
    // Writes JSON array with the list of allocations.
    void BuildStatsString(VmaJsonWriter& json);
#endif

    bool IsEmpty();
    void Register(VmaAllocation alloc);
    void Unregister(VmaAllocation alloc);

private:
    typedef VmaIntrusiveLinkedList<VmaDedicatedAllocationListItemTraits> DedicatedAllocationLinkedList;

    bool m_UseMutex = true;
    VMA_RW_MUTEX m_Mutex;
    DedicatedAllocationLinkedList m_AllocationList;
};

#ifndef _VMA_DEDICATED_ALLOCATION_LIST_FUNCTIONS

VmaDedicatedAllocationList::~VmaDedicatedAllocationList()
{
    VMA_HEAVY_ASSERT(Validate());

    if (!m_AllocationList.IsEmpty())
    {
        VMA_ASSERT(false && "Unfreed dedicated allocations found!");
    }
}

bool VmaDedicatedAllocationList::Validate()
{
    const size_t declaredCount = m_AllocationList.GetCount();
    size_t actualCount = 0;
    VmaMutexLockRead lock(m_Mutex, m_UseMutex);
    for (VmaAllocation alloc = m_AllocationList.Front();
        alloc != VMA_NULL; alloc = m_AllocationList.GetNext(alloc))
    {
        ++actualCount;
    }
    VMA_VALIDATE(actualCount == declaredCount);

    return true;
}

void VmaDedicatedAllocationList::AddDetailedStatistics(VmaDetailedStatistics& inoutStats)
{
    for(auto* item = m_AllocationList.Front(); item != nullptr; item = DedicatedAllocationLinkedList::GetNext(item))
    {
        const VkDeviceSize size = item->GetSize();
        inoutStats.statistics.blockCount++;
        inoutStats.statistics.blockBytes += size;
        VmaAddDetailedStatisticsAllocation(inoutStats, item->GetSize());
    }
}

void VmaDedicatedAllocationList::AddStatistics(VmaStatistics& inoutStats)
{
    VmaMutexLockRead lock(m_Mutex, m_UseMutex);

    const uint32_t allocCount = (uint32_t)m_AllocationList.GetCount();
    inoutStats.blockCount += allocCount;
    inoutStats.allocationCount += allocCount;

    for(auto* item = m_AllocationList.Front(); item != nullptr; item = DedicatedAllocationLinkedList::GetNext(item))
    {
        const VkDeviceSize size = item->GetSize();
        inoutStats.blockBytes += size;
        inoutStats.allocationBytes += size;
    }
}

#if VMA_STATS_STRING_ENABLED
void VmaDedicatedAllocationList::BuildStatsString(VmaJsonWriter& json)
{
    VmaMutexLockRead lock(m_Mutex, m_UseMutex);
    json.BeginArray();
    for (VmaAllocation alloc = m_AllocationList.Front();
        alloc != VMA_NULL; alloc = m_AllocationList.GetNext(alloc))
    {
        json.BeginObject(true);
        alloc->PrintParameters(json);
        json.EndObject();
    }
    json.EndArray();
}
#endif // VMA_STATS_STRING_ENABLED

bool VmaDedicatedAllocationList::IsEmpty()
{
    VmaMutexLockRead lock(m_Mutex, m_UseMutex);
    return m_AllocationList.IsEmpty();
}

void VmaDedicatedAllocationList::Register(VmaAllocation alloc)
{
    VmaMutexLockWrite lock(m_Mutex, m_UseMutex);
    m_AllocationList.PushBack(alloc);
}

void VmaDedicatedAllocationList::Unregister(VmaAllocation alloc)
{
    VmaMutexLockWrite lock(m_Mutex, m_UseMutex);
    m_AllocationList.Remove(alloc);
}
#endif // _VMA_DEDICATED_ALLOCATION_LIST_FUNCTIONS
#endif // _VMA_DEDICATED_ALLOCATION_LIST

#ifndef _VMA_SUBALLOCATION
/*
Represents a region of VmaDeviceMemoryBlock that is either assigned and returned as
allocated memory block or free.
*/
struct VmaSuballocation
{
    VkDeviceSize offset;
    VkDeviceSize size;
    void* userData;
    VmaSuballocationType type;
};

// Comparator for offsets.
struct VmaSuballocationOffsetLess
{
    bool operator()(const VmaSuballocation& lhs, const VmaSuballocation& rhs) const
    {
        return lhs.offset < rhs.offset;
    }
};

struct VmaSuballocationOffsetGreater
{
    bool operator()(const VmaSuballocation& lhs, const VmaSuballocation& rhs) const
    {
        return lhs.offset > rhs.offset;
    }
};

struct VmaSuballocationItemSizeLess
{
    bool operator()(const VmaSuballocationList::iterator lhs,
        const VmaSuballocationList::iterator rhs) const
    {
        return lhs->size < rhs->size;
    }

    bool operator()(const VmaSuballocationList::iterator lhs,
        VkDeviceSize rhsSize) const
    {
        return lhs->size < rhsSize;
    }
};
#endif // _VMA_SUBALLOCATION

#ifndef _VMA_ALLOCATION_REQUEST
/*
Parameters of planned allocation inside a VmaDeviceMemoryBlock.
item points to a FREE suballocation.
*/
struct VmaAllocationRequest
{
    VmaAllocHandle allocHandle;
    VkDeviceSize size;
    VmaSuballocationList::iterator item;
    void* customData;
    uint64_t algorithmData;
    VmaAllocationRequestType type;
};
#endif // _VMA_ALLOCATION_REQUEST

#ifndef _VMA_BLOCK_METADATA
/*
Data structure used for bookkeeping of allocations and unused ranges of memory
in a single VkDeviceMemory block.
*/
class VmaBlockMetadata
{
public: