00001 /* 00002 * Copyright (c) 2006-2009 Erin Catto http://www.gphysics.com 00003 * 00004 * This software is provided 'as-is', without any express or implied 00005 * warranty. In no event will the authors be held liable for any damages 00006 * arising from the use of this software. 00007 * Permission is granted to anyone to use this software for any purpose, 00008 * including commercial applications, and to alter it and redistribute it 00009 * freely, subject to the following restrictions: 00010 * 1. The origin of this software must not be misrepresented; you must not 00011 * claim that you wrote the original software. If you use this software 00012 * in a product, an acknowledgment in the product documentation would be 00013 * appreciated but is not required. 00014 * 2. Altered source versions must be plainly marked as such, and must not be 00015 * misrepresented as being the original software. 00016 * 3. This notice may not be removed or altered from any source distribution. 00017 */ 00018 00019 #ifndef B2_BLOCK_ALLOCATOR_H 00020 #define B2_BLOCK_ALLOCATOR_H 00021 00022 #include <Box2D/Common/b2Settings.h> 00023 00024 const int32 b2_chunkSize = 4096; 00025 const int32 b2_maxBlockSize = 640; 00026 const int32 b2_blockSizes = 14; 00027 const int32 b2_chunkArrayIncrement = 128; 00028 00029 struct b2Block; 00030 struct b2Chunk; 00031 00032 // This is a small object allocator used for allocating small 00033 // objects that persist for more than one time step. 00034 // See: http://www.codeproject.com/useritems/Small_Block_Allocator.asp 00035 class b2BlockAllocator 00036 { 00037 public: 00038 b2BlockAllocator(); 00039 ~b2BlockAllocator(); 00040 00041 void* Allocate(int32 size); 00042 void Free(void* p, int32 size); 00043 00044 void Clear(); 00045 00046 private: 00047 00048 b2Chunk* m_chunks; 00049 int32 m_chunkCount; 00050 int32 m_chunkSpace; 00051 00052 b2Block* m_freeLists[b2_blockSizes]; 00053 00054 static int32 s_blockSizes[b2_blockSizes]; 00055 static uint8 s_blockSizeLookup[b2_maxBlockSize + 1]; 00056 static bool s_blockSizeLookupInitialized; 00057 }; 00058 00059 #endif