1 /* 2 * Copyright (c) 2006-2009 Erin Catto http://www.box2d.org 3 * 4 * This software is provided 'as-is', without any express or implied 5 * warranty. In no event will the authors be held liable for any damages 6 * arising from the use of this software. 7 * Permission is granted to anyone to use this software for any purpose, 8 * including commercial applications, and to alter it and redistribute it 9 * freely, subject to the following restrictions: 10 * 1. The origin of this software must not be misrepresented; you must not 11 * claim that you wrote the original software. If you use this software 12 * in a product, an acknowledgment in the product documentation would be 13 * appreciated but is not required. 14 * 2. Altered source versions must be plainly marked as such, and must not be 15 * misrepresented as being the original software. 16 * 3. This notice may not be removed or altered from any source distribution. 17 */ 18 19 #ifndef B2_BLOCK_ALLOCATOR_H 20 #define B2_BLOCK_ALLOCATOR_H 21 22 #include <Box2D/Common/b2Settings.h> 23 24 const int32 b2_chunkSize = 16 * 1024; 25 const int32 b2_maxBlockSize = 640; 26 const int32 b2_blockSizes = 14; 27 const int32 b2_chunkArrayIncrement = 128; 28 29 struct b2Block; 30 struct b2Chunk; 31 32 /// This is a small object allocator used for allocating small 33 /// objects that persist for more than one time step. 34 /// See: http://www.codeproject.com/useritems/Small_Block_Allocator.asp 35 class b2BlockAllocator 36 { 37 public: 38 b2BlockAllocator(); 39 ~b2BlockAllocator(); 40 41 /// Allocate memory. This will use b2Alloc if the size is larger than b2_maxBlockSize. 42 void* Allocate(int32 size); 43 44 /// Free memory. This will use b2Free if the size is larger than b2_maxBlockSize. 45 void Free(void* p, int32 size); 46 47 void Clear(); 48 49 private: 50 51 b2Chunk* m_chunks; 52 int32 m_chunkCount; 53 int32 m_chunkSpace; 54 55 b2Block* m_freeLists[b2_blockSizes]; 56 57 static int32 s_blockSizes[b2_blockSizes]; 58 static uint8 s_blockSizeLookup[b2_maxBlockSize + 1]; 59 static bool s_blockSizeLookupInitialized; 60 }; 61 62 #endif 63