void Triangulation::calculate_boundaries()
{
_VERBOSE("Triangulation::calculate_boundaries");
get_neighbors(); // Ensure _neighbors has been created.
// Create set of all boundary TriEdges, which are those which do not
// have a neighbor triangle.
typedef std::set<TriEdge> BoundaryEdges;
BoundaryEdges boundary_edges;
for (int tri = 0; tri < _ntri; ++tri) {
if (!is_masked(tri)) {
for (int edge = 0; edge < 3; ++edge) {
if (get_neighbor(tri, edge) == -1) {
boundary_edges.insert(TriEdge(tri, edge));
}
}
}
}
// Take any boundary edge and follow the boundary until return to start
// point, removing edges from boundary_edges as they are used. At the same
// time, initialise the _tri_edge_to_boundary_map.
while (!boundary_edges.empty()) {
// Start of new boundary.
BoundaryEdges::iterator it = boundary_edges.begin();
int tri = it->tri;
int edge = it->edge;
_boundaries.push_back(Boundary());
Boundary& boundary = _boundaries.back();
while (true) {
boundary.push_back(TriEdge(tri, edge));
boundary_edges.erase(it);
_tri_edge_to_boundary_map[TriEdge(tri, edge)] =
BoundaryEdge(_boundaries.size()-1, boundary.size()-1);
// Move to next edge of current triangle.
edge = (edge+1) % 3;
// Find start point index of boundary edge.
int point = get_triangle_point(tri, edge);
// Find next TriEdge by traversing neighbors until find one
// without a neighbor.
while (get_neighbor(tri, edge) != -1) {
tri = get_neighbor(tri, edge);
edge = get_edge_in_triangle(tri, point);
}
if (TriEdge(tri,edge) == boundary.front())
break; // Reached beginning of this boundary, so finished it.
else
it = boundary_edges.find(TriEdge(tri, edge));
}
}
}
BOOL Close()
{
while (true){
//Find an open boundary and close it by a new facet.
cHALF_EDGE *boundaryHalfEdge = BoundaryEdge();
if(boundaryHalfEdge == NULL)
break;
if (!CloseHole(boundaryHalfEdge))
return false;
}
return true;
}
INT BoundaryLength() {
cHALF_EDGE *boundaryEdge = BoundaryEdge();
INT length = 0;
if(boundaryEdge) {
cHALF_EDGE *loopingHe = boundaryEdge;
do {
length++;
loopingHe = loopingHe->Next();
} while(boundaryEdge != loopingHe);
}
return length;
}
BOOL IsClosed() {
return BoundaryEdge() ? false : true ;
}
