private void HandleSplitVertex(TVertex vertex)
{
#if DEBUG
int hs = helpers.Count;
#endif
Debug.Assert(GetVertexType(vertex) == VertexType.Split);
// There are no sweep line status modification to be made from above-incident edges
// Add a diagonal from vertex to the helper of the edge directly to the left
EdgeBase rightmostEdge = RightmostEdge(vertex);
KeyValuePair <EdgeBase, TVertex>?directlyLeft = DirectlyLeftOf(rightmostEdge);
if (directlyLeft.HasValue)
{
TVertex helper = directlyLeft.Value.Value;
DiagonalInserterDelegate(mesh, vertex, helper);
helpers[directlyLeft.Value.Key] = vertex;
}
// Add all of the below-indicent edges into the sweep line status (helpers)
// with this vertex as their helper
IEnumerable <EdgeBase> belowEdges = meshUtilities.BelowEdges(vertex);
foreach (EdgeBase edge in belowEdges)
{
helpers[edge] = vertex;
}
#if DEBUG
Debug.Assert(helpers.Count == hs + belowEdges.Count());
#endif
}
/// <summary>
/// Find the edges which are below-indicent to the given vertex and
/// indicent to the face we are triangulating
/// </summary>
/// <param name="vertex"></param>
/// <returns></returns>
private IEnumerable <EdgeBase> BelowEdges(TVertex vertex)
{
return(meshUtilities.BelowEdges(vertex).Where(e => e.Faces.First == face ||
e.Faces.Second == face));
}