src/BulletCollision/CollisionShapes/btTriangleMesh.cpp

   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
  36         if (m_use32bitIndices)
  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
  50         if (m_use4componentVertices)
  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 {
  67         if (m_use32bitIndices)
  68         {
  69                 m_32bitIndices.push_back(index);
  70                 m_indexedMeshes[0].m_triangleIndexBase = (unsigned char*) &m_32bitIndices[0];
  71         } else
  72         {
  73                 m_16bitIndices.push_back(index);
  74                 m_indexedMeshes[0].m_triangleIndexBase = (unsigned char*) &m_16bitIndices[0];
  75         }
  76 }
  77
  78
  79 int     btTriangleMesh::findOrAddVertex(const btVector3& vertex, bool removeDuplicateVertices)
  80 {
  81         //return index of new/existing vertex
  82         ///@todo: could use acceleration structure for this
  83         if (m_use4componentVertices)
  84         {
  85                 if (removeDuplicateVertices)
  86                         {
  87                         for (int i=0;i< m_4componentVertices.size();i++)
  88                         {
  89                                 if ((m_4componentVertices[i]-vertex).length2() <= m_weldingThreshold)
  90                                 {
  91                                         return i;
  92                                 }
  93                         }
  94                 }
  95                 m_indexedMeshes[0].m_numVertices++;
  96                 m_4componentVertices.push_back(vertex);
  97                 m_indexedMeshes[0].m_vertexBase = (unsigned char*)&m_4componentVertices[0];
  98
  99                 return m_4componentVertices.size()-1;
 100
 101         } else
 102         {
 103
 104                 if (removeDuplicateVertices)
 105                 {
 106                         for (int i=0;i< m_3componentVertices.size();i+=3)
 107                         {
 108                                 btVector3 vtx(m_3componentVertices[i],m_3componentVertices[i+1],m_3componentVertices[i+2]);
 109                                 if ((vtx-vertex).length2() <= m_weldingThreshold)
 110                                 {
 111                                         return i/3;
 112                                 }
 113                         }
 114         }
 115                 m_3componentVertices.push_back((float)vertex.getX());
 116                 m_3componentVertices.push_back((float)vertex.getY());
 117                 m_3componentVertices.push_back((float)vertex.getZ());
 118                 m_indexedMeshes[0].m_numVertices++;
 119                 m_indexedMeshes[0].m_vertexBase = (unsigned char*)&m_3componentVertices[0];
 120                 return (m_3componentVertices.size()/3)-1;
 121         }
 122
 123 }
 124
 125 void    btTriangleMesh::addTriangle(const btVector3& vertex0,const btVector3& vertex1,const btVector3& vertex2,bool removeDuplicateVertices)
 126 {
 127         m_indexedMeshes[0].m_numTriangles++;
 128         addIndex(findOrAddVertex(vertex0,removeDuplicateVertices));
 129         addIndex(findOrAddVertex(vertex1,removeDuplicateVertices));
 130         addIndex(findOrAddVertex(vertex2,removeDuplicateVertices));
 131 }
 132
 133 int btTriangleMesh::getNumTriangles() const
 134 {
 135         if (m_use32bitIndices)
 136         {
 137                 return m_32bitIndices.size() / 3;
 138         }
 139         return m_16bitIndices.size() / 3;
 140 }
 141
 142 void btTriangleMesh::preallocateVertices(int numverts)
 143 {
 144         if (m_use4componentVertices)
 145         {
 146                 m_4componentVertices.reserve(numverts);
 147         } else
 148         {
 149                 m_3componentVertices.reserve(numverts);
 150         }
 151 }
 152
 153 void btTriangleMesh::preallocateIndices(int numindices)
 154 {
 155         if (m_use32bitIndices)
 156         {
 157                 m_32bitIndices.reserve(numindices);
 158         } else
 159         {
 160                 m_16bitIndices.reserve(numindices);
 161         }
 162 }