/// <summary>
/// Triangulate simple polygon with holes
/// </summary>
public static void Triangulate(DTSweepContext tcx)
{
tcx.CreateAdvancingFront();
Sweep(tcx);
FixupConstrainedEdges(tcx);
// Finalize triangulation
if (tcx.TriangulationMode == TriangulationMode.Polygon)
{
FinalizationPolygon(tcx);
}
else
{
FinalizationConvexHull(tcx);
if (tcx.TriangulationMode == TriangulationMode.Constrained)
{
// work in progress. When it's done, call FinalizationConstraints INSTEAD of tcx.FinalizeTriangulation
//FinalizationConstraints(tcx);
tcx.FinalizeTriangulation();
}
else
{
tcx.FinalizeTriangulation();
}
}
tcx.Done();
}
/// <summary>
/// Triangulate simple polygon with holes
/// </summary>
public static void Triangulate(DTSweepContext tcx)
{
tcx.CreateAdvancingFront();
Sweep(tcx);
FixupConstrainedEdges(tcx);
// Finalize triangulation
if (tcx.TriangulationMode == TriangulationMode.Polygon)
{
FinalizationPolygon(tcx);
}
else
{
FinalizationConvexHull(tcx);
if (tcx.TriangulationMode == TriangulationMode.Constrained)
{
// work in progress. When it's done, call FinalizationConstraints INSTEAD of tcx.FinalizeTriangulation
//FinalizationConstraints(tcx);
tcx.FinalizeTriangulation();
}
else
{
tcx.FinalizeTriangulation();
}
}
tcx.Done();
}
/// <summary>
/// If this is a Delaunay Triangulation of a pointset we need to fill so the triangle mesh gets a ConvexHull
/// </summary>
private static void FinalizationConvexHull(DTSweepContext tcx)
{
AdvancingFrontNode n1, n2, n3;
DelaunayTriangle t1;
TriangulationPoint first, p1;
n1 = tcx.Front.Head.Next;
n2 = n1.Next;
n3 = n2.Next;
first = n1.Point;
TurnAdvancingFrontConvex(tcx, n1, n2);
n1 = tcx.Front.Tail.Prev;
if (n1.Triangle.Contains(n1.Next.Point) && n1.Triangle.Contains(n1.Prev.Point))
{
t1 = n1.Triangle.NeighborAcrossFrom(n1.Point);
RotateTrianglePair(n1.Triangle, n1.Point, t1, t1.OppositePoint(n1.Triangle, n1.Point));
tcx.MapTriangleToNodes(n1.Triangle);
tcx.MapTriangleToNodes(t1);
}
n1 = tcx.Front.Head.Next;
if (n1.Triangle.Contains(n1.Prev.Point) && n1.Triangle.Contains(n1.Next.Point))
{
t1 = n1.Triangle.NeighborAcrossFrom(n1.Point);
RotateTrianglePair(n1.Triangle, n1.Point, t1, t1.OppositePoint(n1.Triangle, n1.Point));
tcx.MapTriangleToNodes(n1.Triangle);
tcx.MapTriangleToNodes(t1);
}
// TODO: implement ConvexHull for lower right and left boundary
// Lower right boundary
first = tcx.Front.Head.Point;
n2 = tcx.Front.Tail.Prev;
t1 = n2.Triangle;
p1 = n2.Point;
do
{
tcx.RemoveFromList(t1);
p1 = t1.PointCCWFrom(p1);
if (p1 == first)
{
break;
}
t1 = t1.NeighborCCWFrom(p1);
} while (true);
// Lower left boundary
first = tcx.Front.Head.Next.Point;
p1 = t1.PointCWFrom(tcx.Front.Head.Point);
t1 = t1.NeighborCWFrom(tcx.Front.Head.Point);
do
{
tcx.RemoveFromList(t1);
p1 = t1.PointCCWFrom(p1);
t1 = t1.NeighborCCWFrom(p1);
} while (p1 != first);
tcx.FinalizeTriangulation();
}
/// <summary>
/// If this is a Delaunay Triangulation of a pointset we need to fill so the triangle mesh gets a ConvexHull
/// </summary>
private static void FinalizationConvexHull(DTSweepContext tcx)
{
AdvancingFrontNode n1, n2, n3;
DelaunayTriangle t1;
TriangulationPoint first, p1;
n1 = tcx.Front.Head.Next;
n2 = n1.Next;
n3 = n2.Next;
first = n1.Point;
TurnAdvancingFrontConvex(tcx, n1, n2);
n1 = tcx.Front.Tail.Prev;
if (n1.Triangle.Contains(n1.Next.Point) && n1.Triangle.Contains(n1.Prev.Point))
{
t1 = n1.Triangle.NeighborAcrossFrom(n1.Point);
RotateTrianglePair(n1.Triangle, n1.Point, t1, t1.OppositePoint(n1.Triangle, n1.Point));
tcx.MapTriangleToNodes(n1.Triangle);
tcx.MapTriangleToNodes(t1);
}
n1 = tcx.Front.Head.Next;
if (n1.Triangle.Contains(n1.Prev.Point) && n1.Triangle.Contains(n1.Next.Point))
{
t1 = n1.Triangle.NeighborAcrossFrom(n1.Point);
RotateTrianglePair(n1.Triangle, n1.Point, t1, t1.OppositePoint(n1.Triangle, n1.Point));
tcx.MapTriangleToNodes(n1.Triangle);
tcx.MapTriangleToNodes(t1);
}
// TODO: implement ConvexHull for lower right and left boundary
// Lower right boundary
first = tcx.Front.Head.Point;
n2 = tcx.Front.Tail.Prev;
t1 = n2.Triangle;
p1 = n2.Point;
do
{
tcx.RemoveFromList(t1);
p1 = t1.PointCCWFrom(p1);
if (p1 == first) break;
t1 = t1.NeighborCCWFrom(p1);
} while (true);
// Lower left boundary
first = tcx.Front.Head.Next.Point;
p1 = t1.PointCWFrom(tcx.Front.Head.Point);
t1 = t1.NeighborCWFrom(tcx.Front.Head.Point);
do
{
tcx.RemoveFromList(t1);
p1 = t1.PointCCWFrom(p1);
t1 = t1.NeighborCCWFrom(p1);
} while (p1 != first);
tcx.FinalizeTriangulation();
}
