public static VCircleEvent CircleCheckDataNode(VDataNode n, double ys)
{
VDataNode l = VNode.LeftDataNode(n);
VDataNode r = VNode.RightDataNode(n);
if (l == null || r == null || l.DataPoint == r.DataPoint || l.DataPoint == n.DataPoint || n.DataPoint == r.DataPoint)
{
return(null);
}
if (MathTools.ccw(l.DataPoint[0], l.DataPoint[1], n.DataPoint[0], n.DataPoint[1], r.DataPoint[0], r.DataPoint[1], false) <= 0)
{
return(null);
}
Vector Center = Fortune.CircumCircleCenter(l.DataPoint, n.DataPoint, r.DataPoint);
VCircleEvent VC = new VCircleEvent();
VC.NodeN = n;
VC.NodeL = l;
VC.NodeR = r;
VC.Center = Center;
VC.Valid = true;
if (VC.Y > ys || Math.Abs(VC.Y - ys) < 1e-10)
{
return(VC);
}
return(null);
}
public static VNode ProcessCircleEvent(VCircleEvent e, VNode Root, VoronoiGraph VG, double ys, out VDataNode[] CircleCheckList)
{
VDataNode a, b, c;
VEdgeNode eu, eo;
b = e.NodeN;
a = VNode.LeftDataNode(b);
c = VNode.RightDataNode(b);
if (a == null || b.Parent == null || c == null || !a.DataPoint.Equals(e.NodeL.DataPoint) || !c.DataPoint.Equals(e.NodeR.DataPoint))
{
CircleCheckList = new VDataNode[] {};
return(Root); // Abbruch da sich der Graph verändert hat
}
eu = (VEdgeNode)b.Parent;
CircleCheckList = new VDataNode[] { a, c };
//1. Create the new Vertex
Vector VNew = new Vector(e.Center[0], e.Center[1]);
// VNew[0] = Fortune.ParabolicCut(a.DataPoint[0],a.DataPoint[1],c.DataPoint[0],c.DataPoint[1],ys);
// VNew[1] = (ys + a.DataPoint[1])/2 - 1/(2*(ys-a.DataPoint[1]))*(VNew[0]-a.DataPoint[0])*(VNew[0]-a.DataPoint[0]);
VG.Vertices.Add(VNew);
//2. Find out if a or c are in a distand part of the tree (the other is then b's sibling) and assign the new vertex
if (eu.Left == b) // c is sibling
{
eo = VNode.EdgeToRightDataNode(a);
// replace eu by eu's Right
eu.Parent.Replace(eu, eu.Right);
}
else // a is sibling
{
eo = VNode.EdgeToRightDataNode(b);
// replace eu by eu's Left
eu.Parent.Replace(eu, eu.Left);
}
eu.Edge.AddVertex(VNew);
// ///////////////////// uncertain
// if(eo==eu)
// return Root;
// /////////////////////
//complete & cleanup eo
eo.Edge.AddVertex(VNew);
//while(eo.Edge.VVertexB == Fortune.VVUnkown)
//{
// eo.Flipped = !eo.Flipped;
// eo.Edge.AddVertex(Fortune.VVInfinite);
//}
//if(eo.Flipped)
//{
// Vector T = eo.Edge.LeftData;
// eo.Edge.LeftData = eo.Edge.RightData;
// eo.Edge.RightData = T;
//}
//2. Replace eo by new Edge
VoronoiEdge VE = new VoronoiEdge();
VE.LeftData = a.DataPoint;
VE.RightData = c.DataPoint;
VE.AddVertex(VNew);
VG.Edges.Add(VE);
VEdgeNode VEN = new VEdgeNode(VE, false);
VEN.Left = eo.Left;
VEN.Right = eo.Right;
if (eo.Parent == null)
{
return(VEN);
}
eo.Parent.Replace(eo, VEN);
return(Root);
}