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 btUnionFind::~btUnionFind()
19 {
20 Free();
21 }
22
23 btUnionFind::btUnionFind()
24 {
25 }
26
27 void btUnionFind::allocate(int N)
28 {
29 m_elements.resize(N);
30 }
31 void btUnionFind::Free()
32 {
33 m_elements.clear();
34 }
35
36 void btUnionFind::reset(int N)
37 {
38 allocate(N);
39
40 for (int i = 0; i < N; i++)
41 {
42 m_elements[i].m_id = i;
43 m_elements[i].m_sz = 1;
44 }
45 }
46
47 class btUnionFindElementSortPredicate
48 {
49 public:
50 bool operator()(const btElement& lhs, const btElement& rhs) const
51 {
52 return lhs.m_id < rhs.m_id;
53 }
54 };
55
58 void btUnionFind::sortIslands()
59 {
60 //first store the original body index, and islandId
61 int numElements = m_elements.size();
62
63 for (int i = 0; i < numElements; i++)
64 {
65 m_elements[i].m_id = find(i);
66 #ifndef STATIC_SIMULATION_ISLAND_OPTIMIZATION
67 m_elements[i].m_sz = i;
68 #endif //STATIC_SIMULATION_ISLAND_OPTIMIZATION
69 }
70
71 // Sort the vector using predicate and std::sort
72 //std::sort(m_elements.begin(), m_elements.end(), btUnionFindElementSortPredicate);
73 m_elements.quickSort(btUnionFindElementSortPredicate());
74 }
btAlignedObjectArray::quickSort
void quickSort(const L &CompareFunc)
Definition: btAlignedObjectArray.h:341
btUnionFind::reset
void reset(int N)
Definition: btUnionFind.cpp:36
btAlignedObjectArray::clear
void clear()
clear the array, deallocated memory. Generally it is better to use array.resize(0),...
Definition: btAlignedObjectArray.h:176
btUnionFindElementSortPredicate
Definition: btUnionFind.cpp:48
btUnionFind::sortIslands
void sortIslands()
this is a special operation, destroying the content of btUnionFind.
Definition: btUnionFind.cpp:58
btUnionFind::Free
void Free()
Definition: btUnionFind.cpp:31
btUnionFind::btUnionFind
btUnionFind()
Definition: btUnionFind.cpp:23
btAlignedObjectArray::resize
void resize(int newsize, const T &fillData=T())
Definition: btAlignedObjectArray.h:203
btUnionFindElementSortPredicate::operator()
bool operator()(const btElement &lhs, const btElement &rhs) const
Definition: btUnionFind.cpp:50
btElement::m_id
int m_id
Definition: btUnionFind.h:28
btElement
Definition: btUnionFind.h:27
btUnionFind::~btUnionFind
~btUnionFind()
Definition: btUnionFind.cpp:18
btUnionFind::allocate
void allocate(int N)
Definition: btUnionFind.cpp:27
btUnionFind::m_elements
btAlignedObjectArray< btElement > m_elements
Definition: btUnionFind.h:38
btUnionFind.h
btUnionFind::find
int find(int p, int q)
Definition: btUnionFind.h:71
btAlignedObjectArray::size
int size() const
return the number of elements in the array
Definition: btAlignedObjectArray.h:142