Method convert_triangles_to_quads

tutorials/common/scenegraph/scenegraph.cpp:1253–1290

  }
  
  Ref<SceneGraph::Node> SceneGraph::convert_triangles_to_quads ( Ref<SceneGraph::TriangleMeshNode> tmesh )
  {
    Ref<SceneGraph::QuadMeshNode> qmesh = new SceneGraph::QuadMeshNode(tmesh->material,tmesh->time_range,0);

    for (auto& p : tmesh->positions)
      qmesh->positions.push_back(p);
    
    qmesh->normals = tmesh->normals;
    qmesh->texcoords = tmesh->texcoords;
    
    for (size_t i=0; i<tmesh->triangles.size(); i++)
    {
      const int a0 = tmesh->triangles[i+0].v0;
      const int a1 = tmesh->triangles[i+0].v1;
      const int a2 = tmesh->triangles[i+0].v2;
      if (i+1 == tmesh->triangles.size()) {
        qmesh->quads.push_back(SceneGraph::QuadMeshNode::Quad(a0,a1,a2,a2));
        continue;
      }
      
      const int b0 = tmesh->triangles[i+1].v0;
      const int b1 = tmesh->triangles[i+1].v1;
      const int b2 = tmesh->triangles[i+1].v2;
      const std::pair<int,int> q = quad_index3(a0,a1,a2,b0,b1,b2);
      const int a3 = q.second;
      if (a3 == -1) {
        qmesh->quads.push_back(SceneGraph::QuadMeshNode::Quad(a0,a1,a2,a2));
        continue;
      }
      
      if      (q.first == -1) qmesh->quads.push_back(SceneGraph::QuadMeshNode::Quad(a1,a2,a3,a0));
      else if (q.first ==  0) qmesh->quads.push_back(SceneGraph::QuadMeshNode::Quad(a3,a1,a2,a0));
      else if (q.first ==  1) qmesh->quads.push_back(SceneGraph::QuadMeshNode::Quad(a0,a1,a3,a2));
      else if (q.first ==  2) qmesh->quads.push_back(SceneGraph::QuadMeshNode::Quad(a1,a2,a3,a0)); 
      i++;
    }
    return qmesh.dynamicCast<SceneGraph::Node>();
  }

  Ref<SceneGraph::Node> SceneGraph::convert_triangles_to_quads(Ref<SceneGraph::Node> node, float prop)
  {