/// <summary>
/// Find and mark L edges which are "covered" by the result area (if any).
/// L edges at nodes which also have A edges can be checked by checking
/// their depth at that node.
/// L edges at nodes which do not have A edges can be checked by doing a
/// point-in-polygon test with the previously computed result areas.
/// </summary>
private void FindCoveredLineEdges()
{
// first set covered for all L edges at nodes which have A edges too
for (IEnumerator nodeit = op.Graph.Nodes.GetEnumerator(); nodeit.MoveNext();)
{
Node node = (Node)nodeit.Current;
((DirectedEdgeStar)node.Edges).FindCoveredLineEdges();
}
// For all L edges which weren't handled by the above,
// use a point-in-poly test to determine whether they are covered
for (IEnumerator it = op.Graph.EdgeEnds.GetEnumerator(); it.MoveNext();)
{
DirectedEdge de = (DirectedEdge)it.Current;
Edge e = de.Edge;
if (de.LineEdge && !e.CoveredSet)
{
bool isCovered = op.IsCoveredByA(de.Coordinate);
e.Covered = isCovered;
}
}
}
