public void CheckCircle(BeachArc mid)
{
BeachEdge leftParent = BeachNode.GetLeftParent(mid);
BeachEdge rightParent = BeachNode.GetRightParent(mid);
BeachArc left = BeachNode.GetLeftChild(leftParent);
BeachArc right = BeachNode.GetRightChild(rightParent);
if (left == null || right == null || left.site == right.site)
{
return;
}
Vector2 s = GetEdgeIntersection(leftParent.edge, rightParent.edge);
if (float.IsNaN(s.x) || float.IsNaN(s.y))
{
return;
}
float dx = left.site.pos.x - s.x;
float dy = left.site.pos.y - s.y;
float d = Mathf.Sqrt((dx * dx) + (dy * dy));
if (s.y - d >= sweep)
{
return;
}
VertexEvent ev = new VertexEvent(left, mid, right);
mid.ev = ev;
events.Add(ev);
}
public float GetXOfEdge(BeachEdge n, float y)
{
BeachArc left = BeachNode.GetLeftChild(n);
BeachArc right = BeachNode.GetRightChild(n);
Vector2 p = left.site.pos;
Vector2 r = right.site.pos;
float dp = 2f * (p.y - y);
float a1 = 1f / dp;
float b1 = -2f * p.x / dp;
float c1 = y + dp / 4 + p.x * p.x / dp;
dp = 2f * (r.y - y);
float a2 = 1f / dp;
float b2 = -2f * r.x / dp;
float c2 = sweep + dp / 4 + r.x * r.x / dp;
float a = a1 - a2;
float b = b1 - b2;
float c = c1 - c2;
float disc = b * b - 4 * a * c;
float x1 = (-b + Mathf.Sqrt(disc)) / (2 * a);
float x2 = (-b - Mathf.Sqrt(disc)) / (2 * a);
float xl = Mathf.Min(x1, x2);
float xr = Mathf.Max(x1, x2);
float ry;
if (p.y < r.y)
{
ry = Mathf.Max(x1, x2);
}
else
{
ry = Mathf.Min(x1, x2);
}
return(ry);
/*
* if(p.x < r.x) //going L to R
* {
* if (r.y < p.y)
* return xl;
* else
* return xr;
* }
* else
* {
* if (p.y < r.y)
* return xr;
* else
* return xl;
* }*/
}
public VertexEvent(BeachArc cl, BeachArc cm, BeachArc cr)
{
if (cl == null || cm == null || cr == null)
{
return;
}
arcs = new List <BeachArc>()
{
cl, cm, cr
};
center = CircumcenterPoints(cl.site.pos, cm.site.pos, cr.site.pos);
bottom = new Vector2(center.x, center.y - (cl.site.pos - center).magnitude); //Bottom of the circle
}
public float yCircleCenter; // y-coord of circle, can become cell vertex
/*
* Constructor
*/
public CircleEvent() : base(null, false)
{
arc = null;
x = y = yCircleCenter = 0;
}
public void Insert(Cell c)
{
Vertex start;
Edge edge;
if (root == null)
{
root = new BeachArc(c);
return;
}
if (root.GetType() == typeof(BeachArc) && ((BeachArc)root).site.pos.y - c.pos.y < 1)
{
BeachArc temp = (BeachArc)root;
root = new BeachEdge();
if (c.pos.x < temp.site.pos.x)
{
root.left = new BeachArc(c);
root.right = temp;
}
else
{
root.left = temp;
root.right = new BeachArc(c);
}
start = new Vertex(new Vector2(c.pos.x, GetY(temp.site.pos, c.pos.x)));
diagram.vertices.Add(start);
if (c.pos.x > temp.site.pos.x)
{
edge = new Edge(start, temp.site, c);
((BeachEdge)root).edge = edge;
}
else
{
edge = new Edge(start, c, temp.site);
((BeachEdge)root).edge = edge;
}
diagram.edges.Add(edge);
return;
}
BeachArc par = GetParabolaByX(c.pos.x);
if (par.ev != null) //If hit arc is the center of a triplet, remove it
{
events.Remove(par.ev);
par.ev = null;
}
start = new Vertex(new Vector2(c.pos.x, GetY(par.site.pos, c.pos.x)));
diagram.vertices.Add(start);
Edge left = new Edge(start, par.site, c);
Edge right = new Edge(start, c, par.site);
left.section = right;
diagram.edges.Add(left);
BeachArc p0 = new BeachArc(par.site);
BeachArc p1 = new BeachArc(c);
BeachArc p2 = new BeachArc(par.site);
BeachEdge subroot = new BeachEdge();
subroot.edge = right;
if (par == par.parent.left)
{
par.parent.left = subroot;
}
else
{
par.parent.right = subroot;
}
subroot.right = p2;
subroot.left = new BeachEdge(left);
subroot.left.left = p0;
subroot.left.right = p1;
CheckCircle(p0);
CheckCircle(p2);
}
public void Remove(VertexEvent e)
{
BeachArc mid = e.arcs[1];
BeachEdge leftEdge = BeachNode.GetLeftParent(mid);
BeachEdge rightEdge = BeachNode.GetRightParent(mid);
BeachArc left = BeachNode.GetLeftChild(leftEdge);
BeachArc right = BeachNode.GetRightChild(rightEdge);
if (left.ev != null)
{
events.Remove(left.ev);
left.ev = null;
}
if (right.ev != null)
{
events.Remove(right.ev);
right.ev = null;
}
Vertex end = new Vertex(e.center);
diagram.vertices.Add(end);
leftEdge.edge.end = end;
rightEdge.edge.end = end;
diagram.edges.Add(leftEdge.edge);
diagram.edges.Add(rightEdge.edge);
BeachEdge higher = null;
BeachNode par = mid;
while (par != root)
{
par = par.parent;
if (par == leftEdge)
{
higher = leftEdge;
}
if (par == rightEdge)
{
higher = rightEdge;
}
}
higher.edge = new Edge(end, left.site, right.site);
diagram.edges.Add(higher.edge);
BeachEdge gparent = (BeachEdge)mid.parent.parent;
if (mid.parent.left == mid)
{
if (gparent.left == mid.parent)
{
gparent.left = mid.parent.right;
}
if (gparent.right == mid.parent)
{
gparent.right = mid.parent.right;
}
}
else
{
if (gparent.left == mid.parent)
{
gparent.left = mid.parent.left;
}
if (gparent.right == mid.parent)
{
gparent.right = mid.parent.left;
}
}
CheckCircle(left);
CheckCircle(right);
}
