public int CompareTo(Site s1)
{
var returnValue = Voronoi.CompareByYThenX(this, s1);
int tempIndex;
switch (returnValue)
{
case -1:
if (SiteIndex > s1.SiteIndex)
{
tempIndex = SiteIndex;
SiteIndex = s1.SiteIndex;
s1.SiteIndex = tempIndex;
}
break;
case 1:
if (s1.SiteIndex > SiteIndex)
{
tempIndex = s1.SiteIndex;
s1.SiteIndex = SiteIndex;
SiteIndex = tempIndex;
}
break;
}
return(returnValue);
}
public int CompareTo(object obj)
{
var s2 = (Site)obj;
var returnValue = Voronoi.CompareByYThenX(this, s2);
// swap _siteIndex values if necessary to match new ordering:
int tempIndex;
switch (returnValue)
{
case -1:
if (SiteIndex > s2.SiteIndex)
{
tempIndex = SiteIndex;
SiteIndex = s2.SiteIndex;
s2.SiteIndex = tempIndex;
}
break;
case 1:
if (s2.SiteIndex > SiteIndex)
{
tempIndex = s2.SiteIndex;
s2.SiteIndex = SiteIndex;
SiteIndex = tempIndex;
}
break;
}
return(returnValue);
}
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));
}
