public HalfEdge Init(Edge edge, Side? side)
{
Edge = edge;
LeftOrRight = side;
NextInPriorityQueue = null;
Vertex = null;
return this;
}
public void ReallyDispose()
{
EdgeListLeftNeighbor = null;
EdgeListRightNeighbor = null;
NextInPriorityQueue = null;
Edge = null;
LeftOrRight = null;
Vertex = null;
pool.Push(this);
}
public static Vertex Intersect(HalfEdge halfEdge0, HalfEdge halfEdge1)
{
Edge edge;
HalfEdge halfEdge;
var edge0 = halfEdge0.Edge;
var edge1 = halfEdge1.Edge;
if (edge0 == null || edge1 == null)
{
return null;
}
if (edge0.RightSite == edge1.RightSite)
{
return null;
}
var determinant = edge0.A * edge1.B - edge0.B * edge1.A;
if (-1.0e-10 < determinant && determinant < 1.0e-10)
{
// the edges are parallel
return null;
}
var intersectionX = (edge0.C * edge1.B - edge1.C * edge0.B) / determinant;
var intersectionY = (edge1.C * edge0.A - edge0.C * edge1.A) / determinant;
if (Voronoi.CompareByYThenX(edge0.RightSite, edge1.RightSite) < 0)
{
halfEdge = halfEdge0;
edge = edge0;
}
else
{
halfEdge = halfEdge1;
edge = edge1;
}
var rightOfSite = intersectionX >= edge.RightSite.X;
if ((rightOfSite && halfEdge.LeftOrRight == Side.Left) || (!rightOfSite && halfEdge.LeftOrRight == Side.Right))
return null;
return Create(intersectionX, intersectionY);
}
public void Insert(HalfEdge halfEdge)
{
HalfEdge next;
var insertionBucket = Bucket(halfEdge);
if (insertionBucket < minBucket)
{
minBucket = insertionBucket;
}
var previous = hash[insertionBucket];
while ((next = previous.NextInPriorityQueue) != null
&& (halfEdge.YStar > next.YStar || (halfEdge.YStar == next.YStar && halfEdge.Vertex.X > next.Vertex.X)))
{
previous = next;
}
halfEdge.NextInPriorityQueue = previous.NextInPriorityQueue;
previous.NextInPriorityQueue = halfEdge;
count++;
}
public void Dispose()
{
var halfEdge = LeftEnd;
while (halfEdge != RightEnd)
{
var prevHalfEdge = halfEdge;
halfEdge = halfEdge.EdgeListRightNeighbor;
prevHalfEdge.Dispose();
}
LeftEnd = null;
RightEnd.Dispose();
RightEnd = null;
int i;
//todo: might not be needed
for (i = 0; i < hashSize; ++i)
{
hash[i] = null;
}
hash = null;
}
public void Remove(HalfEdge halfEdge)
{
halfEdge.EdgeListLeftNeighbor.EdgeListRightNeighbor = halfEdge.EdgeListRightNeighbor;
halfEdge.EdgeListRightNeighbor.EdgeListLeftNeighbor = halfEdge.EdgeListLeftNeighbor;
halfEdge.Edge = Edge.Deleted;
halfEdge.EdgeListLeftNeighbor = halfEdge.EdgeListRightNeighbor = null;
}
public void Insert(HalfEdge lb, HalfEdge newHalfEdge)
{
newHalfEdge.EdgeListLeftNeighbor = lb;
newHalfEdge.EdgeListRightNeighbor = lb.EdgeListRightNeighbor;
lb.EdgeListRightNeighbor.EdgeListLeftNeighbor = newHalfEdge;
lb.EdgeListRightNeighbor = newHalfEdge;
}
private static Site RightRegion(HalfEdge halfEdge, Site bottomMostSite)
{
var edge = halfEdge.Edge;
return edge == null ? bottomMostSite : edge.Site(SideHelper.Other((Side)halfEdge.LeftOrRight));
}
public void Remove(HalfEdge halfEdge)
{
HalfEdge previous;
var removalBucket = Bucket(halfEdge);
if (halfEdge.Vertex == null) return;
previous = hash[removalBucket];
while (previous.NextInPriorityQueue != halfEdge)
{
previous = previous.NextInPriorityQueue;
}
previous.NextInPriorityQueue = halfEdge.NextInPriorityQueue;
count--;
halfEdge.Vertex = null;
halfEdge.NextInPriorityQueue = null;
halfEdge.Dispose();
}
private int Bucket(HalfEdge halfEdge)
{
var theBucket = (int)((halfEdge.YStar - yMin) / deltaY * hashSize);
if (theBucket < 0)
theBucket = 0;
if (theBucket >= hashSize)
theBucket = hashSize - 1;
return theBucket;
}
