Blender  V3.3
btHashedSimplePairCache.cpp
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1 /*
2 Bullet Continuous Collision Detection and Physics Library
3 Copyright (c) 2003-2006 Erwin Coumans http://continuousphysics.com/Bullet/
4 
5 This software is provided 'as-is', without any express or implied warranty.
6 In no event will the authors be held liable for any damages 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 freely,
9 subject to the following restrictions:
10 
11 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.
12 2. Altered source versions must be plainly marked as such, and must not be misrepresented as being the original software.
13 3. This notice may not be removed or altered from any source distribution.
14 */
15 
17 
18 #include <stdio.h>
19 
20 #ifdef BT_DEBUG_COLLISION_PAIRS
21 int gOverlappingSimplePairs = 0;
22 int gRemoveSimplePairs = 0;
23 int gAddedSimplePairs = 0;
24 int gFindSimplePairs = 0;
25 #endif //BT_DEBUG_COLLISION_PAIRS
26 
28 {
29  int initialAllocatedSize = 2;
30  m_overlappingPairArray.reserve(initialAllocatedSize);
31  growTables();
32 }
33 
35 {
36 }
37 
39 {
40  m_overlappingPairArray.clear();
42  m_next.clear();
43 
44  int initialAllocatedSize = 2;
45  m_overlappingPairArray.reserve(initialAllocatedSize);
46  growTables();
47 }
48 
50 {
51 #ifdef BT_DEBUG_COLLISION_PAIRS
52  gFindSimplePairs++;
53 #endif
54 
55  /*if (indexA > indexB)
56  btSwap(indexA, indexB);*/
57 
58  int hash = static_cast<int>(getHash(static_cast<unsigned int>(indexA), static_cast<unsigned int>(indexB)) & (m_overlappingPairArray.capacity() - 1));
59 
60  if (hash >= m_hashTable.size())
61  {
62  return NULL;
63  }
64 
65  int index = m_hashTable[hash];
66  while (index != BT_SIMPLE_NULL_PAIR && equalsPair(m_overlappingPairArray[index], indexA, indexB) == false)
67  {
68  index = m_next[index];
69  }
70 
71  if (index == BT_SIMPLE_NULL_PAIR)
72  {
73  return NULL;
74  }
75 
76  btAssert(index < m_overlappingPairArray.size());
77 
78  return &m_overlappingPairArray[index];
79 }
80 
81 //#include <stdio.h>
82 
83 void btHashedSimplePairCache::growTables()
84 {
85  int newCapacity = m_overlappingPairArray.capacity();
86 
87  if (m_hashTable.size() < newCapacity)
88  {
89  //grow hashtable and next table
90  int curHashtableSize = m_hashTable.size();
91 
92  m_hashTable.resize(newCapacity);
93  m_next.resize(newCapacity);
94 
95  int i;
96 
97  for (i = 0; i < newCapacity; ++i)
98  {
100  }
101  for (i = 0; i < newCapacity; ++i)
102  {
104  }
105 
106  for (i = 0; i < curHashtableSize; i++)
107  {
108  const btSimplePair& pair = m_overlappingPairArray[i];
109  int indexA = pair.m_indexA;
110  int indexB = pair.m_indexB;
111 
112  int hashValue = static_cast<int>(getHash(static_cast<unsigned int>(indexA), static_cast<unsigned int>(indexB)) & (m_overlappingPairArray.capacity() - 1)); // New hash value with new mask
113  m_next[i] = m_hashTable[hashValue];
114  m_hashTable[hashValue] = i;
115  }
116  }
117 }
118 
119 btSimplePair* btHashedSimplePairCache::internalAddPair(int indexA, int indexB)
120 {
121  int hash = static_cast<int>(getHash(static_cast<unsigned int>(indexA), static_cast<unsigned int>(indexB)) & (m_overlappingPairArray.capacity() - 1)); // New hash value with new mask
122 
123  btSimplePair* pair = internalFindPair(indexA, indexB, hash);
124  if (pair != NULL)
125  {
126  return pair;
127  }
128 
129  int count = m_overlappingPairArray.size();
130  int oldCapacity = m_overlappingPairArray.capacity();
131  void* mem = &m_overlappingPairArray.expandNonInitializing();
132 
133  int newCapacity = m_overlappingPairArray.capacity();
134 
135  if (oldCapacity < newCapacity)
136  {
137  growTables();
138  //hash with new capacity
139  hash = static_cast<int>(getHash(static_cast<unsigned int>(indexA), static_cast<unsigned int>(indexB)) & (m_overlappingPairArray.capacity() - 1));
140  }
141 
142  pair = new (mem) btSimplePair(indexA, indexB);
143 
144  pair->m_userPointer = 0;
145 
148 
149  return pair;
150 }
151 
153 {
154 #ifdef BT_DEBUG_COLLISION_PAIRS
155  gRemoveSimplePairs++;
156 #endif
157 
158  /*if (indexA > indexB)
159  btSwap(indexA, indexB);*/
160 
161  int hash = static_cast<int>(getHash(static_cast<unsigned int>(indexA), static_cast<unsigned int>(indexB)) & (m_overlappingPairArray.capacity() - 1));
162 
163  btSimplePair* pair = internalFindPair(indexA, indexB, hash);
164  if (pair == NULL)
165  {
166  return 0;
167  }
168 
169  void* userData = pair->m_userPointer;
170 
171  int pairIndex = int(pair - &m_overlappingPairArray[0]);
172  btAssert(pairIndex < m_overlappingPairArray.size());
173 
174  // Remove the pair from the hash table.
175  int index = m_hashTable[hash];
176  btAssert(index != BT_SIMPLE_NULL_PAIR);
177 
178  int previous = BT_SIMPLE_NULL_PAIR;
179  while (index != pairIndex)
180  {
181  previous = index;
182  index = m_next[index];
183  }
184 
185  if (previous != BT_SIMPLE_NULL_PAIR)
186  {
187  btAssert(m_next[previous] == pairIndex);
188  m_next[previous] = m_next[pairIndex];
189  }
190  else
191  {
192  m_hashTable[hash] = m_next[pairIndex];
193  }
194 
195  // We now move the last pair into spot of the
196  // pair being removed. We need to fix the hash
197  // table indices to support the move.
198 
199  int lastPairIndex = m_overlappingPairArray.size() - 1;
200 
201  // If the removed pair is the last pair, we are done.
202  if (lastPairIndex == pairIndex)
203  {
204  m_overlappingPairArray.pop_back();
205  return userData;
206  }
207 
208  // Remove the last pair from the hash table.
209  const btSimplePair* last = &m_overlappingPairArray[lastPairIndex];
210  /* missing swap here too, Nat. */
211  int lastHash = static_cast<int>(getHash(static_cast<unsigned int>(last->m_indexA), static_cast<unsigned int>(last->m_indexB)) & (m_overlappingPairArray.capacity() - 1));
212 
213  index = m_hashTable[lastHash];
214  btAssert(index != BT_SIMPLE_NULL_PAIR);
215 
216  previous = BT_SIMPLE_NULL_PAIR;
217  while (index != lastPairIndex)
218  {
219  previous = index;
220  index = m_next[index];
221  }
222 
223  if (previous != BT_SIMPLE_NULL_PAIR)
224  {
225  btAssert(m_next[previous] == lastPairIndex);
226  m_next[previous] = m_next[lastPairIndex];
227  }
228  else
229  {
230  m_hashTable[lastHash] = m_next[lastPairIndex];
231  }
232 
233  // Copy the last pair into the remove pair's spot.
234  m_overlappingPairArray[pairIndex] = m_overlappingPairArray[lastPairIndex];
235 
236  // Insert the last pair into the hash table
237  m_next[pairIndex] = m_hashTable[lastHash];
238  m_hashTable[lastHash] = pairIndex;
239 
240  m_overlappingPairArray.pop_back();
241 
242  return userData;
243 }
244 //#include <stdio.h>
const int BT_SIMPLE_NULL_PAIR
#define btAssert(x)
Definition: btScalar.h:295
SIMD_FORCE_INLINE void reserve(int _Count)
SIMD_FORCE_INLINE void clear()
clear the array, deallocated memory. Generally it is better to use array.resize(0),...
SIMD_FORCE_INLINE int capacity() const
return the pre-allocated (reserved) elements, this is at least as large as the total number of elemen...
SIMD_FORCE_INLINE int size() const
return the number of elements in the array
SIMD_FORCE_INLINE void pop_back()
SIMD_FORCE_INLINE void resize(int newsize, const T &fillData=T())
SIMD_FORCE_INLINE T & expandNonInitializing()
btAlignedObjectArray< int > m_hashTable
btAlignedObjectArray< int > m_next
btSimplePair * findPair(int indexA, int indexB)
virtual void * removeOverlappingPair(int indexA, int indexB)
int count
#define hash
Definition: noise.c:153