/// <summary>
/// Circles the check data node.
/// </summary>
/// <returns>
/// The check data node.
/// </returns>
/// <param name='n'>
/// N.
/// </param>
/// <param name='ys'>
/// Ys.
/// </param>
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.X, l.DataPoint.Y, n.DataPoint.X, n.DataPoint.Y, r.DataPoint.X, r.DataPoint.Y, false) <= 0)
{
return(null);
}
Vector2D 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)
{
return(VC);
}
return(null);
}
/// <summary>
/// Processes the circle event.
/// </summary>
/// <returns>
/// The circle event.
/// </returns>
/// <param name='e'>
/// E.
/// </param>
/// <param name='Root'>
/// Root.
/// </param>
/// <param name='VG'>
/// V.
/// </param>
/// <param name='ys'>
/// Ys.
/// </param>
/// <param name='CircleCheckList'>
/// Circle check list.
/// </param>
public static VNode ProcessCircleEvent(VCircleEvent e, VNode Root, VoronoiGraph VG, double ys, out VDataNode[] CircleCheckList)
{
VDataNode a;
VDataNode b;
VDataNode c;
VEdgeNode eu;
VEdgeNode 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 ver 0/00ndert hat
}
eu = b.Parent as VEdgeNode;
CircleCheckList = new VDataNode[] { a, c };
//1. Create the new Vertex
Vector2D VNew = new Vector2D(e.Center.X, e.Center.Y);
VG.Vertizes.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);
eo.Edge.AddVertex(VNew);
//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);
}
