Exemplo n.º 1
0
 /// <summary>
 /// Exhaustive search to update neighbor pointers
 /// </summary>
 /// <param name="t"></param>
 public void MarkNeighbor(Triangle t)
 {
     if (t.Contains(Points[1], Points[2]))
     {
         _neighbours[0] = t;
         t.MarkNeighbor(Points[1], Points[2], this);
     }
     else if (t.Contains(Points[0], Points[2]))
     {
         _neighbours[1] = t;
         t.MarkNeighbor(Points[0], Points[2], this);
     }
     else if (t.Contains(Points[0], Points[1]))
     {
         _neighbours[2] = t;
         t.MarkNeighbor(Points[0], Points[1], this);
     }
 }
Exemplo n.º 2
0
        private void EdgeEvent(SweepContext tcx, TriPoint ep, TriPoint eq, Triangle triangle, TriPoint point)
        {
            if (IsEdgeSideOfTriangle(triangle, ep, eq))
            {
                return;
            }

            TriPoint p1 = triangle.PointCCW(point);
            Winding  o1 = TriUtil.Orient2d(eq, p1, ep);

            if (o1 == Winding.Collinear)
            {
                if (triangle.Contains(eq, p1))
                {
                    triangle.MarkConstrainedEdge(eq, p1);
                    // We are modifying the constraint maybe it would be better to
                    // not change the given constraint and just keep a variable for the new constraint
                    tcx.EdgeEvent.ConstrainedEdge.Q = p1;
                    triangle = triangle.NeighborAcross(point);
                    EdgeEvent(tcx, ep, p1, triangle, p1);
                }
                else
                {
                    throw new NotSupportedException("EdgeEvent - collinear points not supported");
                }

                return;
            }

            TriPoint p2 = triangle.PointCW(point);
            Winding  o2 = TriUtil.Orient2d(eq, p2, ep);

            if (o2 == Winding.Collinear)
            {
                if (triangle.Contains(eq, p2))
                {
                    triangle.MarkConstrainedEdge(eq, p2);
                    // We are modifying the constraint maybe it would be better to
                    // not change the given constraint and just keep a variable for the new constraint
                    tcx.EdgeEvent.ConstrainedEdge.Q = p2;
                    triangle = triangle.NeighborAcross(point);
                    EdgeEvent(tcx, ep, p2, triangle, p2);
                }
                else
                {
                    throw new NotSupportedException("EdgeEvent - collinear points not supported");
                }

                return;
            }

            if (o1 == o2)
            {
                // Need to decide if we are rotating CW or CCW to get to a triangle
                // that will cross edge
                if (o1 == Winding.CW)
                {
                    triangle = triangle.NeighborCCW(point);
                }
                else
                {
                    triangle = triangle.NeighborCW(point);
                }
                EdgeEvent(tcx, ep, eq, triangle, point);
            }
            else
            {
                // This triangle crosses constraint so lets flippin start!
                FlipEdgeEvent(tcx, ep, eq, triangle, point);
            }
        }