Engine/lib/bullet/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 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
  89         ///@todo: could use acceleration structure for this
  90         if (m_use4componentVertices)
  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++;
 103                 m_4componentVertices.push_back(vertex);
 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                         {
 115                                 btVector3 vtx(m_3componentVertices[i],m_3componentVertices[i+1],m_3componentVertices[i+2]);
 116                                 if ((vtx-vertex).length2() <= m_weldingThreshold)
 117                                 {
 118                                         return i/3;
 119                                 }
 120                         }
 121                 }
 122                 m_3componentVertices.push_back(vertex.getX());
 123                 m_3componentVertices.push_back(vertex.getY());
 124                 m_3componentVertices.push_back(vertex.getZ());
 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
 140 int btTriangleMesh::getNumTriangles() const
 141 {
 142         if (m_use32bitIndices)
 143         {
 144                 return m_32bitIndices.size() / 3;
 145         }
 146         return m_16bitIndices.size() / 3;
 147 }
 148
 149 void btTriangleMesh::preallocateVertices(int numverts)
 150 {
 151         if (m_use4componentVertices)
 152         {
 153                 m_4componentVertices.reserve(numverts);
 154         } else
 155         {
 156                 m_3componentVertices.reserve(numverts);
 157         }
 158 }
 159
 160 void btTriangleMesh::preallocateIndices(int numindices)
 161 {
 162         if (m_use32bitIndices)
 163         {
 164                 m_32bitIndices.reserve(numindices);
 165         } else
 166         {
 167                 m_16bitIndices.reserve(numindices);
 168         }
 169 }