/// <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(); }