/// <summary>
/// Tries to find an already existing halfedge for the given vertices
/// </summary>
/// <param name="origin"></param>
/// <param name="target"></param>
/// <param name="result">The matching halfedge, or null</param>
/// <returns>true on success, false on failure</returns>
public static bool TryGetHalfEdge(Vertex origin, Vertex target, out HalfEdge result)
{
result = null;
if (origin.Outgoing == null)
{
return(false);
}
// get vertex ring iterator around origin
var iterator = new VertexEdgeRingIterator(origin);
var outgoing = iterator.GetOutgoingEnumerator();
foreach (var edge in iterator.GetOutgoingEnumerator())
{
if (edge.Target != target)
{
continue;
}
result = edge;
return(true);
}
return(false);
}
internal static bool TryShiftOutgoing(Vertex vertex)
{
try
{
var iter =
new VertexEdgeRingIterator(vertex)
.GetOutgoingEnumerator()
.Where(e => !EdgeLinker.IsDummyPairEdge(e)) // Only shift to a valid edge
.ToArray();
if (iter.Length <= 1)
{
vertex.Outgoing = null;
return(false);
}
vertex.Outgoing = iter[1];
return(true);
}
catch (Exception)
{
// TODO: evaluate exception, or even better, fix it
vertex.Outgoing = null;
return(false);
}
}
