Bullet Collision Detection & Physics Library
btTriangleMesh.cpp
Go to the documentation of this file.
1 /*
2 Bullet Continuous Collision Detection and Physics Library
3 Copyright (c) 2003-2009 Erwin Coumans http://bulletphysics.org
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 
17 #include "btTriangleMesh.h"
18 
19 
20 
21 btTriangleMesh::btTriangleMesh (bool use32bitIndices,bool use4componentVertices)
22 :m_use32bitIndices(use32bitIndices),
23 m_use4componentVertices(use4componentVertices),
24 m_weldingThreshold(0.0)
25 {
26  btIndexedMesh meshIndex;
27  meshIndex.m_numTriangles = 0;
28  meshIndex.m_numVertices = 0;
29  meshIndex.m_indexType = PHY_INTEGER;
30  meshIndex.m_triangleIndexBase = 0;
31  meshIndex.m_triangleIndexStride = 3*sizeof(int);
32  meshIndex.m_vertexBase = 0;
33  meshIndex.m_vertexStride = sizeof(btVector3);
34  m_indexedMeshes.push_back(meshIndex);
35 
37  {
38  m_indexedMeshes[0].m_numTriangles = m_32bitIndices.size()/3;
39  m_indexedMeshes[0].m_triangleIndexBase = 0;
40  m_indexedMeshes[0].m_indexType = PHY_INTEGER;
41  m_indexedMeshes[0].m_triangleIndexStride = 3*sizeof(int);
42  } else
43  {
44  m_indexedMeshes[0].m_numTriangles = m_16bitIndices.size()/3;
45  m_indexedMeshes[0].m_triangleIndexBase = 0;
46  m_indexedMeshes[0].m_indexType = PHY_SHORT;
47  m_indexedMeshes[0].m_triangleIndexStride = 3*sizeof(short int);
48  }
49 
51  {
52  m_indexedMeshes[0].m_numVertices = m_4componentVertices.size();
53  m_indexedMeshes[0].m_vertexBase = 0;
54  m_indexedMeshes[0].m_vertexStride = sizeof(btVector3);
55  } else
56  {
57  m_indexedMeshes[0].m_numVertices = m_3componentVertices.size()/3;
58  m_indexedMeshes[0].m_vertexBase = 0;
59  m_indexedMeshes[0].m_vertexStride = 3*sizeof(btScalar);
60  }
61 
62 
63 }
64 
65 void btTriangleMesh::addIndex(int index)
66 {
68  {
70  m_indexedMeshes[0].m_triangleIndexBase = (unsigned char*) &m_32bitIndices[0];
71  } else
72  {
74  m_indexedMeshes[0].m_triangleIndexBase = (unsigned char*) &m_16bitIndices[0];
75  }
76 }
77 
78 void btTriangleMesh::addTriangleIndices(int index1, int index2, int index3 )
79 {
80  m_indexedMeshes[0].m_numTriangles++;
81  addIndex( index1 );
82  addIndex( index2 );
83  addIndex( index3 );
84 }
85 
86 int btTriangleMesh::findOrAddVertex(const btVector3& vertex, bool removeDuplicateVertices)
87 {
88  //return index of new/existing vertex
91  {
92  if (removeDuplicateVertices)
93  {
94  for (int i=0;i< m_4componentVertices.size();i++)
95  {
96  if ((m_4componentVertices[i]-vertex).length2() <= m_weldingThreshold)
97  {
98  return i;
99  }
100  }
101  }
102  m_indexedMeshes[0].m_numVertices++;
104  m_indexedMeshes[0].m_vertexBase = (unsigned char*)&m_4componentVertices[0];
105 
106  return m_4componentVertices.size()-1;
107 
108  } else
109  {
110 
111  if (removeDuplicateVertices)
112  {
113  for (int i=0;i< m_3componentVertices.size();i+=3)
114  {
116  if ((vtx-vertex).length2() <= m_weldingThreshold)
117  {
118  return i/3;
119  }
120  }
121  }
125  m_indexedMeshes[0].m_numVertices++;
126  m_indexedMeshes[0].m_vertexBase = (unsigned char*)&m_3componentVertices[0];
127  return (m_3componentVertices.size()/3)-1;
128  }
129 
130 }
131 
132 void btTriangleMesh::addTriangle(const btVector3& vertex0,const btVector3& vertex1,const btVector3& vertex2,bool removeDuplicateVertices)
133 {
134  m_indexedMeshes[0].m_numTriangles++;
135  addIndex(findOrAddVertex(vertex0,removeDuplicateVertices));
136  addIndex(findOrAddVertex(vertex1,removeDuplicateVertices));
137  addIndex(findOrAddVertex(vertex2,removeDuplicateVertices));
138 }
139 
141 {
142  if (m_use32bitIndices)
143  {
144  return m_32bitIndices.size() / 3;
145  }
146  return m_16bitIndices.size() / 3;
147 }
148 
150 {
152  {
153  m_4componentVertices.reserve(numverts);
154  } else
155  {
156  m_3componentVertices.reserve(numverts);
157  }
158 }
159 
161 {
162  if (m_use32bitIndices)
163  {
164  m_32bitIndices.reserve(numindices);
165  } else
166  {
167  m_16bitIndices.reserve(numindices);
168  }
169 }
void push_back(const T &_Val)
The btIndexedMesh indexes a single vertex and index array.
btAlignedObjectArray< btScalar > m_3componentVertices
btAlignedObjectArray< unsigned int > m_32bitIndices
btScalar m_weldingThreshold
PHY_ScalarType m_indexType
const btScalar & getZ() const
Return the z value.
Definition: btVector3.h:577
void addIndex(int index)
addIndex is an internal method, use addTriangle instead
int size() const
return the number of elements in the array
void addTriangleIndices(int index1, int index2, int index3)
Add a triangle using its indices. Make sure the indices are pointing within the vertices array...
bool m_use4componentVertices
const btScalar & getY() const
Return the y value.
Definition: btVector3.h:575
const btScalar & getX() const
Return the x value.
Definition: btVector3.h:573
const unsigned char * m_triangleIndexBase
virtual void preallocateIndices(int numindices)
btAlignedObjectArray< unsigned short int > m_16bitIndices
btTriangleMesh(bool use32bitIndices=true, bool use4componentVertices=true)
int findOrAddVertex(const btVector3 &vertex, bool removeDuplicateVertices)
findOrAddVertex is an internal method, use addTriangle instead
btVector3 can be used to represent 3D points and vectors.
Definition: btVector3.h:83
btAlignedObjectArray< btVector3 > m_4componentVertices
virtual void preallocateVertices(int numverts)
void addTriangle(const btVector3 &vertex0, const btVector3 &vertex1, const btVector3 &vertex2, bool removeDuplicateVertices=false)
By default addTriangle won&#39;t search for duplicate vertices, because the search is very slow for large...
int getNumTriangles() const
float btScalar
The btScalar type abstracts floating point numbers, to easily switch between double and single floati...
Definition: btScalar.h:292
const unsigned char * m_vertexBase