/// <summary>
/// construct EdgeSpan from a list of edges of mesh
/// </summary>
public static EdgeSpan FromEdges(DMesh3 mesh, IList <int> edges)
{
int[] Edges = new int[edges.Count];
for (int i = 0; i < Edges.Length; ++i)
{
Edges[i] = edges[i];
}
int[] Vertices = new int[Edges.Length + 1];
Index2i start_ev = mesh.GetEdgeV(Edges[0]);
Index2i prev_ev = start_ev;
if (Edges.Length > 1)
{
for (int i = 1; i < Edges.Length; ++i)
{
Index2i next_ev = mesh.GetEdgeV(Edges[i]);
Vertices[i] = IndexUtil.find_shared_edge_v(ref prev_ev, ref next_ev);
prev_ev = next_ev;
}
Vertices[0] = IndexUtil.find_edge_other_v(ref start_ev, Vertices[1]);
Vertices[Vertices.Length - 1] = IndexUtil.find_edge_other_v(prev_ev, Vertices[Vertices.Length - 2]);
}
else
{
Vertices[0] = start_ev[0]; Vertices[1] = start_ev[1];
}
return(new EdgeSpan(mesh, Vertices, Edges, false));
}
void find_cut_paths(HashSet <int> CutEdges)
{
Spans = new List <EdgeSpan>();
Loops = new List <EdgeLoop>();
// [TODO] what about if vert appears more than twice in list? we should check for that!
var Remaining = new HashSet <int>(CutEdges);
while (Remaining.Count > 0)
{
int start_edge = Remaining.First();
Remaining.Remove(start_edge);
Index2i start_edge_v = Mesh.GetEdgeV(start_edge);
bool isLoop;
List <int> forwardSpan = walk_edge_span_forward(Mesh, start_edge, start_edge_v.a, Remaining, out isLoop);
if (isLoop == false)
{
List <int> backwardSpan = walk_edge_span_forward(Mesh, start_edge, start_edge_v.b, Remaining, out isLoop);
if (isLoop)
{
throw new Exception("find_cut_paths: how did this possibly happen?!?");
}
if (backwardSpan.Count > 1)
{
backwardSpan.Reverse();
backwardSpan.RemoveAt(backwardSpan.Count - 1);
backwardSpan.AddRange(forwardSpan);
Index2i start_ev = Mesh.GetEdgeV(backwardSpan[0]);
Index2i end_ev = Mesh.GetEdgeV(backwardSpan[backwardSpan.Count - 1]);
// [RMS] >2 check here catches two-edge span case, where we do have shared vert but
// can never be loop unless we have duplicate edge (!)
isLoop = backwardSpan.Count > 2 && IndexUtil.find_shared_edge_v(ref start_ev, ref end_ev) != DMesh3.InvalidID;
forwardSpan = backwardSpan;
}
}
if (isLoop)
{
var loop = EdgeLoop.FromEdges(Mesh, forwardSpan);
Util.gDevAssert(loop.CheckValidity());
Loops.Add(loop);
}
else
{
var span = EdgeSpan.FromEdges(Mesh, forwardSpan);
Util.gDevAssert(span.CheckValidity());
Spans.Add(span);
}
}
}
/// <summary>
/// construct EdgeLoop from a list of edges of mesh
/// </summary>
public static EdgeLoop FromEdges(DMesh3 mesh, IList <int> edges)
{
int[] Edges = new int[edges.Count];
for (int i = 0; i < Edges.Length; ++i)
{
Edges[i] = edges[i];
}
int[] Vertices = new int[Edges.Length];
Index2i start_ev = mesh.GetEdgeV(Edges[0]);
Index2i prev_ev = start_ev;
for (int i = 1; i < Edges.Length; ++i)
{
Index2i next_ev = mesh.GetEdgeV(Edges[i % Edges.Length]);
Vertices[i] = IndexUtil.find_shared_edge_v(ref prev_ev, ref next_ev);
prev_ev = next_ev;
}
Vertices[0] = IndexUtil.find_edge_other_v(ref start_ev, Vertices[1]);
return(new EdgeLoop(mesh, Vertices, Edges, false));
}
