Bullet Collision Detection & Physics Library: btUnionFind.cpp Source File

Bullet Collision Detection & Physics Library

btUnionFind.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
16 #include "btUnionFind.h"
17
18
19
20 btUnionFind::~btUnionFind()
21 {
22 Free();
23
24 }
25
26 btUnionFind::btUnionFind()
27 {
28
29 }
30
31 void btUnionFind::allocate(int N)
32 {
33 m_elements.resize(N);
34 }
35 void btUnionFind::Free()
36 {
37 m_elements.clear();
38 }
39
40
41 void btUnionFind::reset(int N)
42 {
43 allocate(N);
44
45 for (int i = 0; i < N; i++)
46 {
47 m_elements[i].m_id = i; m_elements[i].m_sz = 1;
48 }
49 }
50
51
52 class btUnionFindElementSortPredicate
53 {
54 public:
55
56 bool operator() ( const btElement& lhs, const btElement& rhs ) const
57 {
58 return lhs.m_id < rhs.m_id;
59 }
60 };
61
64 void btUnionFind::sortIslands()
65 {
66
67 //first store the original body index, and islandId
68 int numElements = m_elements.size();
69
70 for (int i=0;i<numElements;i++)
71 {
72 m_elements[i].m_id = find(i);
73 #ifndef STATIC_SIMULATION_ISLAND_OPTIMIZATION
74 m_elements[i].m_sz = i;
75 #endif //STATIC_SIMULATION_ISLAND_OPTIMIZATION
76 }
77
78 // Sort the vector using predicate and std::sort
79 //std::sort(m_elements.begin(), m_elements.end(), btUnionFindElementSortPredicate);
80 m_elements.quickSort(btUnionFindElementSortPredicate());
81
82 }
btUnionFind::sortIslands
void sortIslands()
this is a special operation, destroying the content of btUnionFind.
Definition: btUnionFind.cpp:64
btUnionFind::find
int find(int p, int q)
Definition: btUnionFind.h:76
btUnionFind.h
btUnionFind::reset
void reset(int N)
Definition: btUnionFind.cpp:41
btUnionFind::Free
void Free()
Definition: btUnionFind.cpp:35
btAlignedObjectArray::clear
void clear()
clear the array, deallocated memory. Generally it is better to use array.resize(0), to reduce performance overhead of run-time memory (de)allocations.
Definition: btAlignedObjectArray.h:190
btUnionFind::btUnionFind
btUnionFind()
Definition: btUnionFind.cpp:26
btUnionFind::~btUnionFind
~btUnionFind()
Definition: btUnionFind.cpp:20
btAlignedObjectArray::size
int size() const
return the number of elements in the array
Definition: btAlignedObjectArray.h:155
btAlignedObjectArray::resize
void resize(int newsize, const T &fillData=T())
Definition: btAlignedObjectArray.h:218
btElement::m_id
int m_id
Definition: btUnionFind.h:28
btUnionFind::m_elements
btAlignedObjectArray< btElement > m_elements
Definition: btUnionFind.h:38
btAlignedObjectArray::quickSort
void quickSort(const L &CompareFunc)
Definition: btAlignedObjectArray.h:363
btUnionFindElementSortPredicate
Definition: btUnionFind.cpp:52
btElement
Definition: btUnionFind.h:26
btUnionFind::allocate
void allocate(int N)
Definition: btUnionFind.cpp:31