Esempio n. 1
0
        public void MeshClean(Triangle triangle)
        {
            List <Triangle> triangles = new List <Triangle>();

            triangles.Add(triangle);

            while (triangles.Count != 0)
            {
                int      last = triangles.Count - 1;
                Triangle t    = triangles[last];
                triangles.RemoveAt(last);

                if (t != null && !t.IsInterior())
                {
                    t.IsInterior(true);
                    _triangles.Add(t);
                    for (int i = 0; i < 3; i++)
                    {
                        if (!t.ConstrainedEdge[i])
                        {
                            triangles.Add(t.GetNeighbor(i));
                        }
                    }
                }
            }
        }
Esempio n. 2
0
 public void MapTriangleToNodes(Triangle t)
 {
     for (int i = 0; i < 3; i++)
     {
         if (t.GetNeighbor(i) == null)
         {
             Node n = Front.LocatePoint(t.PointCW(t.Points[i]));
             if (n != null)
             {
                 n.Triangle = t;
             }
         }
     }
 }
Esempio n. 3
0
        private bool IsEdgeSideOfTriangle(Triangle triangle, TriPoint ep, TriPoint eq)
        {
            int index = triangle.EdgeIndex(ep, eq);

            if (index != -1)
            {
                triangle.MarkConstrainedEdge(index);
                Triangle t = triangle.GetNeighbor(index);
                if (t != null)
                {
                    t.MarkConstrainedEdge(ep, eq);
                }

                return(true);
            }

            return(false);
        }
Esempio n. 4
0
        private bool Legalize(SweepContext tcx, Triangle t)
        {
            // To legalize a triangle we start by finding if any of the three edges
            // violate the Delaunay condition
            for (int i = 0; i < 3; i++)
            {
                if (t.DelaunayEdge[i])
                {
                    continue;
                }

                Triangle ot = t.GetNeighbor(i);

                if (ot != null)
                {
                    TriPoint p  = t.Points[i];
                    TriPoint op = ot.OppositePoint(t, p);
                    int      oi = ot.Index(op);

                    // If this is a Constrained Edge or a Delaunay Edge(only during recursive legalization)
                    // then we should not try to legalize
                    if (ot.ConstrainedEdge[oi] || ot.DelaunayEdge[oi])
                    {
                        t.ConstrainedEdge[i] = ot.ConstrainedEdge[oi];
                        continue;
                    }

                    bool inside = Incircle(p, t.PointCCW(p), t.PointCW(p), op);

                    if (inside)
                    {
                        // Lets mark this shared edge as Delaunay
                        t.DelaunayEdge[i]   = true;
                        ot.DelaunayEdge[oi] = true;

                        // Lets rotate shared edge one vertex CW to legalize it
                        RotateTrianglePair(t, p, ot, op);

                        // We now got one valid Delaunay Edge shared by two triangles
                        // This gives us 4 new edges to check for Delaunay

                        // Make sure that triangle to node mapping is done only one time for a specific triangle
                        bool not_legalized = !Legalize(tcx, t);
                        if (not_legalized)
                        {
                            tcx.MapTriangleToNodes(t);
                        }

                        not_legalized = !Legalize(tcx, ot);
                        if (not_legalized)
                        {
                            tcx.MapTriangleToNodes(ot);
                        }

                        // Reset the Delaunay edges, since they only are valid Delaunay edges
                        // until we add a new triangle or point.
                        // XXX: need to think about this. Can these edges be tried after we
                        //      return to previous recursive level?
                        t.DelaunayEdge[i]   = false;
                        ot.DelaunayEdge[oi] = false;

                        // If triangle have been legalized no need to check the other edges since
                        // the recursive legalization will handles those so we can end here.
                        return(true);
                    }
                }
            }

            return(false);
        }