/// <summary>
///
/// </summary>
/// <param name="de"></param>
public void ComputeDepths(DirectedEdge de)
{
int edgeIndex = FindIndex(de);
int startDepth = de.GetDepth(Positions.Left);
int targetLastDepth = de.GetDepth(Positions.Right);
// compute the depths from this edge up to the end of the edge array
int nextDepth = ComputeDepths(edgeIndex + 1, edgeList.Count, startDepth);
// compute the depths for the initial part of the array
int lastDepth = ComputeDepths(0, edgeIndex, nextDepth);
if (lastDepth != targetLastDepth)
throw new TopologyException("depth mismatch at " + de.Coordinate);
}
/// <summary>
///
/// </summary>
/// <param name="de"></param>
public void ComputeDepths(DirectedEdge de)
{
int edgeIndex = FindIndex(de);
int startDepth = de.GetDepth(Positions.Left);
int targetLastDepth = de.GetDepth(Positions.Right);
// compute the depths from this edge up to the end of the edge array
int nextDepth = ComputeDepths(edgeIndex + 1, edgeList.Count, startDepth);
// compute the depths for the initial part of the array
int lastDepth = ComputeDepths(0, edgeIndex, nextDepth);
if (lastDepth != targetLastDepth)
{
throw new TopologyException("depth mismatch at " + de.Coordinate);
}
}
/// <summary>
/// Compute the DirectedEdge depths for a subsequence of the edge array.
/// </summary>
/// <returns>The last depth assigned (from the R side of the last edge visited).</returns>
private int ComputeDepths(int startIndex, int endIndex, int startDepth)
{
int currDepth = startDepth;
for (int i = startIndex; i < endIndex; i++)
{
DirectedEdge nextDe = (DirectedEdge)edgeList[i];
nextDe.SetEdgeDepths(Positions.Right, currDepth);
currDepth = nextDe.GetDepth(Positions.Left);
}
return(currDepth);
}
/// <summary>
/// Finds all non-horizontal segments intersecting the stabbing line
/// in the input dirEdge.
/// The stabbing line is the ray to the right of stabbingRayLeftPt.
/// </summary>
/// <param name="stabbingRayLeftPt">The left-hand origin of the stabbing line.</param>
/// <param name="dirEdge"></param>
/// <param name="stabbedSegments">The current list of DepthSegments intersecting the stabbing line.</param>
private void FindStabbedSegments(ICoordinate stabbingRayLeftPt, DirectedEdge dirEdge, IList stabbedSegments)
{
ICoordinate[] pts = dirEdge.Edge.Coordinates;
for (int i = 0; i < pts.Length - 1; i++)
{
seg.P0 = pts[i];
seg.P1 = pts[i + 1];
// ensure segment always points upwards
if (seg.P0.Y > seg.P1.Y)
seg.Reverse();
// skip segment if it is left of the stabbing line
double maxx = Math.Max(seg.P0.X, seg.P1.X);
if (maxx < stabbingRayLeftPt.X) continue;
// skip horizontal segments (there will be a non-horizontal one carrying the same depth info
if (seg.IsHorizontal) continue;
// skip if segment is above or below stabbing line
if (stabbingRayLeftPt.Y < seg.P0.Y || stabbingRayLeftPt.Y > seg.P1.Y) continue;
// skip if stabbing ray is right of the segment
if (CGAlgorithms.ComputeOrientation(seg.P0, seg.P1, stabbingRayLeftPt) == CGAlgorithms.Right) continue;
// stabbing line cuts this segment, so record it
int depth = dirEdge.GetDepth(Positions.Left);
// if segment direction was flipped, use RHS depth instead
if (! seg.P0.Equals(pts[i]))
depth = dirEdge.GetDepth(Positions.Right);
DepthSegment ds = new DepthSegment(seg, depth);
stabbedSegments.Add(ds);
}
}
/// <summary>
///
/// </summary>
/// <param name="de"></param>
private void CopySymDepths(DirectedEdge de)
{
DirectedEdge sym = de.Sym;
sym.SetDepth(Positions.Left, de.GetDepth(Positions.Right));
sym.SetDepth(Positions.Right, de.GetDepth(Positions.Left));
}