Line data    Source code

       1             : /* Copyright (C) 2022 Wildfire Games.
       2             :  * This file is part of 0 A.D.
       3             :  *
       4             :  * 0 A.D. is free software: you can redistribute it and/or modify
       5             :  * it under the terms of the GNU General Public License as published by
       6             :  * the Free Software Foundation, either version 2 of the License, or
       7             :  * (at your option) any later version.
       8             :  *
       9             :  * 0 A.D. is distributed in the hope that it will be useful,
      10             :  * but WITHOUT ANY WARRANTY; without even the implied warranty of
      11             :  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
      12             :  * GNU General Public License for more details.
      13             :  *
      14             :  * You should have received a copy of the GNU General Public License
      15             :  * along with 0 A.D.  If not, see <http://www.gnu.org/licenses/>.
      16             :  */
      17             : 
      18             : /*
      19             :  * Allocate and destroy CVertexBuffers
      20             :  */
      21             : 
      22             : #ifndef INCLUDED_VERTEXBUFFERMANAGER
      23             : #define INCLUDED_VERTEXBUFFERMANAGER
      24             : 
      25             : #include "lib/types.h"
      26             : #include "renderer/VertexBuffer.h"
      27             : 
      28             : #include <memory>
      29             : #include <utility>
      30             : #include <vector>
      31             : 
      32             : // CVertexBufferManager: owner object for CVertexBuffer objects; acts as
      33             : // 'front end' for their allocation and destruction
      34           2 : class CVertexBufferManager
      35             : {
      36             : public:
      37             :     enum class Group : u32
      38             :     {
      39             :         DEFAULT,
      40             :         TERRAIN,
      41             :         WATER,
      42             :         COUNT
      43             :     };
      44             : 
      45             :     // Helper for automatic VBChunk lifetime management.
      46             :     class Handle
      47             :     {
      48             :     public:
      49          24 :         Handle() = default;
      50             :         Handle(const Handle&) = delete;
      51             :         Handle& operator=(const Handle&) = delete;
      52             : 
      53             :         explicit Handle(CVertexBuffer::VBChunk* chunk);
      54             :         Handle(Handle&& other);
      55             :         Handle& operator=(Handle&& other);
      56             : 
      57          36 :         ~Handle() { Reset(); }
      58             : 
      59         126 :         bool IsValid() const { return m_Chunk != nullptr; }
      60          12 :         explicit operator bool() const { return IsValid(); }
      61          12 :         bool operator!() const { return !static_cast<bool>(*this); }
      62             :         void Reset();
      63             : 
      64           6 :         friend void swap(Handle& lhs, Handle& rhs)
      65             :         {
      66             :             using std::swap;
      67             : 
      68           6 :             swap(lhs.m_Chunk, rhs.m_Chunk);
      69           6 :         }
      70             : 
      71             :         CVertexBuffer::VBChunk& operator*() const { return *m_Chunk; }
      72           6 :         CVertexBuffer::VBChunk* operator->() const { return m_Chunk; }
      73           6 :         CVertexBuffer::VBChunk* Get() const { return m_Chunk; }
      74             : 
      75             :     private:
      76             :         CVertexBuffer::VBChunk* m_Chunk = nullptr;
      77             :     };
      78             : 
      79             :     /**
      80             :      * Try to allocate a vertex buffer of the given size and type.
      81             :      *
      82             :      * @param vertexSize size of each vertex in the buffer
      83             :      * @param numberOfVertices number of vertices in the buffer
      84             :      * @param type buffer type
      85             :      * @param dynamic will be buffer updated frequently or not
      86             :      * @param backingStore if not dynamic, this is nullptr; else for dynamic,
      87             :      *            this must be a copy of the vertex data that remains valid for the
      88             :      *            lifetime of the VBChunk
      89             :      * @return chunk, or empty handle if no free chunks available
      90             :      */
      91             :     Handle AllocateChunk(
      92             :         const size_t vertexSize, const size_t numberOfVertices,
      93             :         const Renderer::Backend::IBuffer::Type type,
      94             :         const bool dynamic, void* backingStore = nullptr, Group group = Group::DEFAULT);
      95             : 
      96             :     /// Returns the given @p chunk to its owning buffer
      97             :     void Release(CVertexBuffer::VBChunk* chunk);
      98             : 
      99             :     size_t GetBytesReserved() const;
     100             :     size_t GetBytesAllocated() const;
     101             : 
     102             :     /// Explicit shutdown of the vertex buffer subsystem; releases all currently-allocated buffers.
     103             :     void Shutdown();
     104             : 
     105             : private:
     106             : 
     107             :     /// List of all known vertex buffers
     108             :     std::vector<std::unique_ptr<CVertexBuffer>> m_Buffers[static_cast<std::size_t>(Group::COUNT)];
     109             : };
     110             : 
     111             : extern CVertexBufferManager g_VBMan;
     112             : 
     113             : #endif