1 /* 2 Copyright (c) 2003-2006 Gino van den Bergen / Erwin Coumans http://continuousphysics.com/Bullet/ 3 4 This software is provided 'as-is', without any express or implied warranty. 5 In no event will the authors be held liable for any damages arising from the use of this software. 6 Permission is granted to anyone to use this software for any purpose, 7 including commercial applications, and to alter it and redistribute it freely, 8 subject to the following restrictions: 9 10 1. The origin of this software must not be misrepresented; you must not claim that you wrote the original software. If you use this software in a product, an acknowledgment in the product documentation would be appreciated but is not required. 11 2. Altered source versions must be plainly marked as such, and must not be misrepresented as being the original software. 12 3. This notice may not be removed or altered from any source distribution. 13 */ 14 15 #ifndef _BT_POOL_ALLOCATOR_H 16 #define _BT_POOL_ALLOCATOR_H 17 18 #include "btScalar.h" 19 #include "btAlignedAllocator.h" 20 #include "btThreads.h" 21 22 ///The btPoolAllocator class allows to efficiently allocate a large pool of objects, instead of dynamically allocating them separately. 23 class btPoolAllocator 24 { 25 int m_elemSize; 26 int m_maxElements; 27 int m_freeCount; 28 void* m_firstFree; 29 unsigned char* m_pool; 30 btSpinMutex m_mutex; // only used if BT_THREADSAFE 31 32 public: btPoolAllocator(int elemSize,int maxElements)33 btPoolAllocator(int elemSize, int maxElements) 34 : m_elemSize(elemSize), 35 m_maxElements(maxElements) 36 { 37 m_pool = (unsigned char*)btAlignedAlloc(static_cast<unsigned int>(m_elemSize * m_maxElements), 16); 38 39 unsigned char* p = m_pool; 40 m_firstFree = p; 41 m_freeCount = m_maxElements; 42 int count = m_maxElements; 43 while (--count) 44 { 45 *(void**)p = (p + m_elemSize); 46 p += m_elemSize; 47 } 48 *(void**)p = 0; 49 } 50 ~btPoolAllocator()51 ~btPoolAllocator() 52 { 53 btAlignedFree(m_pool); 54 } 55 getFreeCount()56 int getFreeCount() const 57 { 58 return m_freeCount; 59 } 60 getUsedCount()61 int getUsedCount() const 62 { 63 return m_maxElements - m_freeCount; 64 } 65 getMaxCount()66 int getMaxCount() const 67 { 68 return m_maxElements; 69 } 70 allocate(int size)71 void* allocate(int size) 72 { 73 // release mode fix 74 (void)size; 75 btMutexLock(&m_mutex); 76 btAssert(!size || size <= m_elemSize); 77 //btAssert(m_freeCount>0); // should return null if all full 78 void* result = m_firstFree; 79 if (NULL != m_firstFree) 80 { 81 m_firstFree = *(void**)m_firstFree; 82 --m_freeCount; 83 } 84 btMutexUnlock(&m_mutex); 85 return result; 86 } 87 validPtr(void * ptr)88 bool validPtr(void* ptr) 89 { 90 if (ptr) 91 { 92 if (((unsigned char*)ptr >= m_pool && (unsigned char*)ptr < m_pool + m_maxElements * m_elemSize)) 93 { 94 return true; 95 } 96 } 97 return false; 98 } 99 freeMemory(void * ptr)100 void freeMemory(void* ptr) 101 { 102 if (ptr) 103 { 104 btAssert((unsigned char*)ptr >= m_pool && (unsigned char*)ptr < m_pool + m_maxElements * m_elemSize); 105 106 btMutexLock(&m_mutex); 107 *(void**)ptr = m_firstFree; 108 m_firstFree = ptr; 109 ++m_freeCount; 110 btMutexUnlock(&m_mutex); 111 } 112 } 113 getElementSize()114 int getElementSize() const 115 { 116 return m_elemSize; 117 } 118 getPoolAddress()119 unsigned char* getPoolAddress() 120 { 121 return m_pool; 122 } 123 getPoolAddress()124 const unsigned char* getPoolAddress() const 125 { 126 return m_pool; 127 } 128 }; 129 130 #endif //_BT_POOL_ALLOCATOR_H 131