void CMesh::Simplify(int iVertices2Remain, float fMaxError, bool bConsiderMaterials)
{
TEdge *pEdge;
bool bRemoveSecond;
m_bConsiderMaterials = bConsiderMaterials;
if (!m_arrCollapses.m_iCount) {
InitOutputs();
InitBorders();
}
InitEdgeEvaluation();
while (m_hashVertices.m_iCount > iVertices2Remain) {
if (!SelectEdge(pEdge, bRemoveSecond, fMaxError))
break;
RecordCollapse(pEdge, bRemoveSecond);
CollapseEdge(pEdge, bRemoveSecond);
// CheckEdges();
}
}
////////////////////////////////////////////////////////////////////////
// MergeVertices
/// merges two vertices and restructures the adjacent elements.
void MergeVertices(Grid& grid, Vertex* v1, Vertex* v2)
{
// make sure that GRIDOPT_VERTEXCENTRIC_INTERCONNECTION is enabled
if(grid.num_edges() && (!grid.option_is_enabled(VRTOPT_STORE_ASSOCIATED_EDGES))) {
LOG(" WARNING in MergeVertices: autoenabling VRTOPT_STORE_ASSOCIATED_EDGES\n");
grid.enable_options(VRTOPT_STORE_ASSOCIATED_EDGES);
}
if(grid.num_faces() && (!grid.option_is_enabled(VRTOPT_STORE_ASSOCIATED_FACES))) {
LOG(" WARNING in MergeVertices: autoenabling VRTOPT_STORE_ASSOCIATED_FACES\n");
grid.enable_options(VRTOPT_STORE_ASSOCIATED_FACES);
}
if(grid.num_volumes() && (!grid.option_is_enabled(VRTOPT_STORE_ASSOCIATED_VOLUMES))) {
LOG(" WARNING in MergeVertices: autoenabling VRTOPT_STORE_ASSOCIATED_VOLUMES\n");
grid.enable_options(VRTOPT_STORE_ASSOCIATED_VOLUMES);
}
Edge* conEdge = grid.get_edge(v1, v2);
if(conEdge) {
// perform an edge-collapse on conEdge
CollapseEdge(grid, conEdge, v1);
}
else {
// notify the grid, that the two vertices will be merged
grid.objects_will_be_merged(v1, v1, v2);
// we have to check if there are elements that connect the vertices.
// We have to delete those.
EraseConnectingElements(grid, v1, v2);
// create new edges for each edge that is connected with v2.
// avoid double edges
if(grid.num_edges() > 0)
{
EdgeDescriptor ed;
Grid::AssociatedEdgeIterator iterEnd = grid.associated_edges_end(v2);
for(Grid::AssociatedEdgeIterator iter = grid.associated_edges_begin(v2); iter != iterEnd; ++iter)
{
Edge* e = *iter;
if(e->vertex(0) == v2)
ed.set_vertices(v1, e->vertex(1));
else
ed.set_vertices(e->vertex(0), v1);
Edge* existingEdge = grid.get_edge(ed);
if(!existingEdge)
grid.create_by_cloning(e, ed, e);
else
grid.objects_will_be_merged(existingEdge, existingEdge, e);
}
}
// create new faces for each face that is connected to v2
// avoid double faces.
if(grid.num_faces() > 0)
{
FaceDescriptor fd;
Grid::AssociatedFaceIterator iterEnd = grid.associated_faces_end(v2);
for(Grid::AssociatedFaceIterator iter = grid.associated_faces_begin(v2); iter != iterEnd; ++iter)
{
Face* f = *iter;
uint numVrts = f->num_vertices();
fd.set_num_vertices(numVrts);
for(uint i = 0; i < numVrts; ++i)
{
if(f->vertex(i) == v2)
fd.set_vertex(i, v1);
else
fd.set_vertex(i, f->vertex(i));
}
Face* existingFace = grid.get_face(fd);
if(!existingFace)
grid.create_by_cloning(f, fd, f);
else
grid.objects_will_be_merged(existingFace, existingFace, f);
}
}
// create new volumes for each volume that is connected to v2
if(grid.num_volumes() > 0)
{
VolumeDescriptor vd;
Grid::AssociatedVolumeIterator iterEnd = grid.associated_volumes_end(v2);
for(Grid::AssociatedVolumeIterator iter = grid.associated_volumes_begin(v2); iter != iterEnd; ++iter)
{
Volume* v = *iter;
uint numVrts = v->num_vertices();
vd.set_num_vertices(numVrts);
for(uint i = 0; i < numVrts; ++i)
{
if(v->vertex(i) == v2)
vd.set_vertex(i, v1);
else
vd.set_vertex(i, v->vertex(i));
}
//assert(!"avoid double volumes! implement FindVolume and use it here.");
grid.create_by_cloning(v, vd, v);
}
}
// new elements have been created. remove the old ones.
// it is sufficient to simply erase v2.
grid.erase(v2);
}
}
