CVertexBuffer Class Reference

CVertexBuffer: encapsulation of backend buffers, also supplying some additional functionality for sharing buffers between multiple objects. More...

#include <VertexBuffer.h>

Classes
struct	VBChunk

Public Member Functions
	CVertexBuffer (Renderer::Backend::IDevice *device, const char *name, const size_t vertexSize, const Renderer::Backend::IBuffer::Type type, const uint32_t usage)
	CVertexBuffer (Renderer::Backend::IDevice *device, const char *name, const size_t vertexSize, const Renderer::Backend::IBuffer::Type type, const uint32_t usage, const size_t maximumBufferSize)
	~CVertexBuffer ()
void	UploadIfNeeded (Renderer::Backend::IDeviceCommandContext *deviceCommandContext)
void	PrepareForRendering (VBChunk *chunk)
	Make the vertex data available for the next usage. More...
void	UpdateChunkVertices (VBChunk *chunk, void *data)
	Update vertex data for given chunk. Transfers the provided data to the actual OpenGL vertex buffer. More...
size_t	GetVertexSize () const
size_t	GetBytesReserved () const
size_t	GetBytesAllocated () const
bool	CompatibleVertexType (const size_t vertexSize, const Renderer::Backend::IBuffer::Type type, const uint32_t usage) const
	Returns true if this vertex buffer is compatible with the specified vertex type and intended usage. More...
void	DumpStatus () const
Renderer::Backend::IBuffer *	GetBuffer ()

Static Public Member Functions
static bool	UseStreaming (const uint32_t usage)
	Given the usage flags of a buffer that has been (or will be) allocated: More...

Private Member Functions
	NONCOPYABLE (CVertexBuffer)
VBChunk *	Allocate (const size_t vertexSize, const size_t numberOfVertices, const Renderer::Backend::IBuffer::Type type, const uint32_t usage, void *backingStore)
	Try to allocate a buffer of given number of vertices (each of given size), and with the given type - return null if no free chunks available. More...
void	Release (VBChunk *chunk)
	Return given chunk to this buffer. More...

Private Attributes
size_t	m_VertexSize
	Vertex size of this vertex buffer. More...
size_t	m_MaxVertices
	Number of vertices of above size in this buffer. More...
std::vector< VBChunk * >	m_FreeList
	List of free chunks in this buffer. More...
std::vector< VBChunk * >	m_AllocList
	List of allocated chunks. More...
size_t	m_FreeVertices
	Available free vertices - total of all free vertices in the free list. More...
std::unique_ptr< Renderer::Backend::IBuffer >	m_Buffer
bool	m_HasNeededChunks

Friends
class	CVertexBufferManager

Detailed Description

CVertexBuffer: encapsulation of backend buffers, also supplying some additional functionality for sharing buffers between multiple objects.

The class can be used in two modes, depending on the usage parameter:

Static buffer: Call Allocate() with backingStore = nullptr. Then call UpdateChunkVertices() with any pointer - the data will be immediately copied to the buffer. This should be used for vertex data that rarely changes.

Dynamic buffer: Call Allocate() with backingStore pointing at some memory that will remain valid for the lifetime of the CVertexBuffer. This should be used for vertex data that may change every frame. Rendering is expected to occur in two phases:

• "Prepare" phase: If this chunk is going to be used for rendering during the next rendering phase, you must call PrepareForRendering(). If the vertex data in backingStore has been modified since the last uploading phase, you must call UpdateChunkVertices().
• "Upload" phase: UploadedIfNeeded() can be called (multiple times). The vertex data will be uploaded to the GPU if necessary. It is okay to have multiple prepare/upload cycles per frame (though slightly less efficient), but they must occur sequentially.

Constructor & Destructor Documentation

CVertexBuffer() [1/2]

CVertexBuffer::CVertexBuffer	(	Renderer::Backend::IDevice *	device,
		const char *	name,
		const size_t	vertexSize,
		const Renderer::Backend::IBuffer::Type	type,
		const uint32_t	usage
	)

CVertexBuffer() [2/2]

CVertexBuffer::CVertexBuffer	(	Renderer::Backend::IDevice *	device,
		const char *	name,
		const size_t	vertexSize,
		const Renderer::Backend::IBuffer::Type	type,
		const uint32_t	usage,
		const size_t	maximumBufferSize
	)

~CVertexBuffer()

CVertexBuffer::~CVertexBuffer

(

)

Member Function Documentation

Allocate()

CVertexBuffer::VBChunk * CVertexBuffer::Allocate ( const size_t  vertexSize, const size_t  numberOfVertices, const Renderer::Backend::IBuffer::Type  type, const uint32_t  usage, void *  backingStore  )

private

Try to allocate a buffer of given number of vertices (each of given size), and with the given type - return null if no free chunks available.

CompatibleVertexType()

bool CVertexBuffer::CompatibleVertexType	(	const size_t	vertexSize,
		const Renderer::Backend::IBuffer::Type	type,
		const uint32_t	usage
	)		const

Returns true if this vertex buffer is compatible with the specified vertex type and intended usage.

DumpStatus()

void CVertexBuffer::DumpStatus

(

)

const

GetBuffer()

Renderer::Backend::IBuffer * CVertexBuffer::GetBuffer ( )

inline

GetBytesAllocated()

size_t CVertexBuffer::GetBytesAllocated

(

)

const

GetBytesReserved()

size_t CVertexBuffer::GetBytesReserved

(

)

const

GetVertexSize()

size_t CVertexBuffer::GetVertexSize ( ) const

inline

NONCOPYABLE()

CVertexBuffer::NONCOPYABLE ( CVertexBuffer  )

private

PrepareForRendering()

void CVertexBuffer::PrepareForRendering

(

VBChunk *

chunk

)

Make the vertex data available for the next usage.

Release()

void CVertexBuffer::Release ( VBChunk *  chunk )

private

Return given chunk to this buffer.

UpdateChunkVertices()

void CVertexBuffer::UpdateChunkVertices	(	VBChunk *	chunk,
		void *	data
	)

Update vertex data for given chunk. Transfers the provided data to the actual OpenGL vertex buffer.

UploadIfNeeded()

void CVertexBuffer::UploadIfNeeded

(

Renderer::Backend::IDeviceCommandContext *

deviceCommandContext

)

UseStreaming()

bool CVertexBuffer::UseStreaming ( const uint32_t  usage )

static

Given the usage flags of a buffer that has been (or will be) allocated:

If true, we assume the buffer is going to be modified on every frame, so we will re-upload the entire buffer every frame using glMapBuffer. This requires the buffer's owner to hold onto its backing store.

If false, we assume it will change rarely, and use direct upload to update it incrementally. The backing store can be freed to save memory.

Friends And Related Function Documentation

CVertexBufferManager

friend class CVertexBufferManager

friend

Member Data Documentation

m_AllocList

std::vector<VBChunk*> CVertexBuffer::m_AllocList

private

List of allocated chunks.

m_Buffer

std::unique_ptr<Renderer::Backend::IBuffer> CVertexBuffer::m_Buffer

private

m_FreeList

std::vector<VBChunk*> CVertexBuffer::m_FreeList

private

List of free chunks in this buffer.

m_FreeVertices

size_t CVertexBuffer::m_FreeVertices

private

Available free vertices - total of all free vertices in the free list.

m_HasNeededChunks

bool CVertexBuffer::m_HasNeededChunks

private

m_MaxVertices

size_t CVertexBuffer::m_MaxVertices

private

Number of vertices of above size in this buffer.

m_VertexSize

size_t CVertexBuffer::m_VertexSize

private

Vertex size of this vertex buffer.

---

The documentation for this class was generated from the following files:

• /home/docker/jenkins/workspace/technical-docs/source/renderer/VertexBuffer.h
• /home/docker/jenkins/workspace/technical-docs/source/renderer/VertexBuffer.cpp