private void fortunesAlgorithm()
{
Site newSite, bottomSite, topSite, tempSite;
Vertex v, vertex;
Vector2 newintstar;
LR leftRight;
Halfedge lbnd, rbnd, llbnd, rrbnd, bisector;
Edge edge;
Rect dataBounds = _sites.getSitesBounds();
int sqrt_nsites = (int)(Mathf.Sqrt(_sites.length + 4));
HalfedgePriorityQueue heap = new HalfedgePriorityQueue(dataBounds.y, dataBounds.height, sqrt_nsites);
EdgeList edgeList = new EdgeList(dataBounds.x, dataBounds.width, sqrt_nsites);
List<Halfedge> halfEdges = new List<Halfedge> ();
List<Vertex> vertices = new List<Vertex>();
Site bottomMostSite = _sites.next();
newSite = _sites.next();
for (;;)
{
if (heap.empty() == false)
{
newintstar = heap.min();
}
if (newSite != null
&& (heap.empty() || compareByYThenX(newSite, newintstar) < 0))
{
/* new site is smallest */
//trace("smallest: new site " + newSite);
// Step 8:
lbnd = edgeList.edgelistLeftNeighbor(newSite.Coord); // the Halfedge just to the left of newSite
//trace("lbnd: " + lbnd);
rbnd = lbnd.edgeListRightNeighbor; // the Halfedge just to the right
//trace("rbnd: " + rbnd);
bottomSite = rightRegion(lbnd,bottomMostSite); // this is the same as leftRegion(rbnd)
// this Site determines the region containing the new site
//trace("new Site is in region of existing site: " + bottomSite);
// Step 9:
edge = Edge.createBisectingEdge(bottomSite, newSite);
//trace("new edge: " + edge);
_edges.Add(edge);
bisector = Halfedge.create(edge, LR.LEFT);
halfEdges.Add(bisector);
// inserting two Halfedges into edgeList constitutes Step 10:
// insert bisector to the right of lbnd:
edgeList.insert(lbnd, bisector);
// first half of Step 11:
if ((vertex = Vertex.intersect(lbnd, bisector)) != null)
{
vertices.Add(vertex);
heap.remove(lbnd);
lbnd.vertex = vertex;
lbnd.ystar = vertex.y + newSite.dist(vertex);
heap.insert(lbnd);
}
lbnd = bisector;
bisector = Halfedge.create(edge, LR.RIGHT);
halfEdges.Add(bisector);
// second Halfedge for Step 10:
// insert bisector to the right of lbnd:
edgeList.insert(lbnd, bisector);
// second half of Step 11:
if ((vertex = Vertex.intersect(bisector, rbnd)) != null)
{
vertices.Add(vertex);
bisector.vertex = vertex;
bisector.ystar = vertex.y + newSite.dist(vertex);
heap.insert(bisector);
}
newSite = _sites.next();
}
else if (heap.empty() == false)
{
/* intersection is smallest */
lbnd = heap.extractMin();
llbnd = lbnd.edgeListLeftNeighbor;
rbnd = lbnd.edgeListRightNeighbor;
rrbnd = rbnd.edgeListRightNeighbor;
bottomSite = leftRegion(lbnd,bottomMostSite);
topSite = rightRegion(rbnd,bottomMostSite);
// these three sites define a Delaunay triangle
// (not actually using these for anything...)
//_triangles.push(new Triangle(bottomSite, topSite, rightRegion(lbnd)));
v = lbnd.vertex;
v.setIndex();
lbnd.edge.setVertex(lbnd.leftRight, v);
rbnd.edge.setVertex(rbnd.leftRight, v);
edgeList.remove(lbnd);
heap.remove(rbnd);
edgeList.remove(rbnd);
leftRight = LR.LEFT;
if (bottomSite.y > topSite.y)
{
tempSite = bottomSite; bottomSite = topSite; topSite = tempSite; leftRight = LR.RIGHT;
}
edge = Edge.createBisectingEdge(bottomSite, topSite);
_edges.Add(edge);
bisector = Halfedge.create(edge, leftRight);
halfEdges.Add(bisector);
edgeList.insert(llbnd, bisector);
edge.setVertex(LR.other(leftRight), v);
if ((vertex = Vertex.intersect(llbnd, bisector)) != null)
{
vertices.Add(vertex);
heap.remove(llbnd);
llbnd.vertex = vertex;
llbnd.ystar = vertex.y + bottomSite.dist(vertex);
heap.insert(llbnd);
}
if ((vertex = Vertex.intersect(bisector, rrbnd)) != null)
{
vertices.Add(vertex);
bisector.vertex = vertex;
bisector.ystar = vertex.y + bottomSite.dist(vertex);
heap.insert(bisector);
}
}
else
{
break;
}
}
// heap should be empty now
heap.dispose();
edgeList.dispose();
// foreach (Halfedge halfEdge in halfEdges)
// {
// halfEdge.reallyDispose();
// }
halfEdges.Clear();// = 0;
// we need the vertices to clip the edges
foreach (Edge edge1 in _edges)
{
edge1.clipVertices(_plotBounds);
}
// but we don't actually ever use them again!
// foreach (vertex in vertices)
// {
// vertex.dispose();
// }
vertices.Clear();// = 0;
}
