Bullet Collision Detection & Physics Library: btPoolAllocator.h Source File

Bullet Collision Detection & Physics Library

btPoolAllocator.h
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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
16 #ifndef _BT_POOL_ALLOCATOR_H
17 #define _BT_POOL_ALLOCATOR_H
18
19 #include "btScalar.h"
20 #include "btAlignedAllocator.h"
21 #include "btThreads.h"
22
24 class btPoolAllocator
25 {
26 int m_elemSize;
27 int m_maxElements;
28 int m_freeCount;
29 void* m_firstFree;
30 unsigned char* m_pool;
31 btSpinMutex m_mutex; // only used if BT_THREADSAFE
32
33 public:
34
35 btPoolAllocator(int elemSize, int maxElements)
36 :m_elemSize(elemSize),
37 m_maxElements(maxElements)
38 {
39 m_pool = (unsigned char*) btAlignedAlloc( static_cast<unsigned int>(m_elemSize*m_maxElements),16);
40
41 unsigned char* p = m_pool;
42 m_firstFree = p;
43 m_freeCount = m_maxElements;
44 int count = m_maxElements;
45 while (--count) {
46 *(void**)p = (p + m_elemSize);
47 p += m_elemSize;
48 }
49 *(void**)p = 0;
50 }
51
52 ~btPoolAllocator()
53 {
54 btAlignedFree( m_pool);
55 }
56
57 int getFreeCount() const
58 {
59 return m_freeCount;
60 }
61
62 int getUsedCount() const
63 {
64 return m_maxElements - m_freeCount;
65 }
66
67 int getMaxCount() const
68 {
69 return m_maxElements;
70 }
71
72 void* allocate(int size)
73 {
74 // release mode fix
75 (void)size;
76 btMutexLock(&m_mutex);
77 btAssert(!size || size<=m_elemSize);
78 //btAssert(m_freeCount>0); // should return null if all full
79 void* result = m_firstFree;
80 if (NULL != m_firstFree)
81 {
82 m_firstFree = *(void**)m_firstFree;
83 --m_freeCount;
84 }
85 btMutexUnlock(&m_mutex);
86 return result;
87 }
88
89 bool validPtr(void* ptr)
90 {
91 if (ptr) {
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
100 void freeMemory(void* ptr)
101 {
102 if (ptr) {
103 btAssert((unsigned char*)ptr >= m_pool && (unsigned char*)ptr < m_pool + m_maxElements * m_elemSize);
104
105 btMutexLock(&m_mutex);
106 *(void**)ptr = m_firstFree;
107 m_firstFree = ptr;
108 ++m_freeCount;
109 btMutexUnlock(&m_mutex);
110 }
111 }
112
113 int getElementSize() const
114 {
115 return m_elemSize;
116 }
117
118 unsigned char* getPoolAddress()
119 {
120 return m_pool;
121 }
122
123 const unsigned char* getPoolAddress() const
124 {
125 return m_pool;
126 }
127
128 };
129
130 #endif //_BT_POOL_ALLOCATOR_H
btPoolAllocator::m_mutex
btSpinMutex m_mutex
Definition: btPoolAllocator.h:31
btMutexLock
void btMutexLock(btSpinMutex *)
Definition: btThreads.h:69
btPoolAllocator::m_firstFree
void * m_firstFree
Definition: btPoolAllocator.h:29
btPoolAllocator::m_elemSize
int m_elemSize
Definition: btPoolAllocator.h:26
size
static DBVT_INLINE btScalar size(const btDbvtVolume &a)
Definition: btDbvt.cpp:52
btAssert
#define btAssert(x)
Definition: btScalar.h:114
btSpinMutex
btSpinMutex – lightweight spin-mutex implemented with atomic ops, never puts a thread to sleep beca...
Definition: btThreads.h:28
btAlignedAllocator.h
btPoolAllocator::getPoolAddress
unsigned char * getPoolAddress()
Definition: btPoolAllocator.h:118
btPoolAllocator::validPtr
bool validPtr(void *ptr)
Definition: btPoolAllocator.h:89
btPoolAllocator::m_maxElements
int m_maxElements
Definition: btPoolAllocator.h:27
btAlignedFree
#define btAlignedFree(ptr)
Definition: btAlignedAllocator.h:48
btPoolAllocator::getUsedCount
int getUsedCount() const
Definition: btPoolAllocator.h:62
btPoolAllocator::btPoolAllocator
btPoolAllocator(int elemSize, int maxElements)
Definition: btPoolAllocator.h:35
btMutexUnlock
void btMutexUnlock(btSpinMutex *)
Definition: btThreads.h:70
btPoolAllocator::getMaxCount
int getMaxCount() const
Definition: btPoolAllocator.h:67
btThreads.h
btPoolAllocator::getElementSize
int getElementSize() const
Definition: btPoolAllocator.h:113
btPoolAllocator::allocate
void * allocate(int size)
Definition: btPoolAllocator.h:72
btPoolAllocator
The btPoolAllocator class allows to efficiently allocate a large pool of objects, instead of dynamica...
Definition: btPoolAllocator.h:24
btPoolAllocator::getFreeCount
int getFreeCount() const
Definition: btPoolAllocator.h:57
btAlignedAlloc
#define btAlignedAlloc(size, alignment)
Definition: btAlignedAllocator.h:47
btPoolAllocator::getPoolAddress
const unsigned char * getPoolAddress() const
Definition: btPoolAllocator.h:123
btPoolAllocator::freeMemory
void freeMemory(void *ptr)
Definition: btPoolAllocator.h:100
btPoolAllocator::m_pool
unsigned char * m_pool
Definition: btPoolAllocator.h:30
btPoolAllocator::~btPoolAllocator
~btPoolAllocator()
Definition: btPoolAllocator.h:52
btScalar.h
btPoolAllocator::m_freeCount
int m_freeCount
Definition: btPoolAllocator.h:28