bool CheckForNewEdgeEvents(BeachLineArc arc)
{
if (arc != null)
{
// Check left and right edge of this arc for intersections.
BeachLineEdge leftEdge = arc.LeftEdge;
BeachLineEdge rightEdge = arc.RightEdge;
if (leftEdge != null && rightEdge != null)
{
// Check for edge intersection
Vector2 intersection;
if (leftEdge.CheckIntersection(rightEdge, out intersection))
{
// These edges intersect. We need to add a new edge event.
// This event may invalidate a previous one. Search for an existing event for this arc.
foreach (VoronoiEvent e in events)
{
if (e is EdgeEvent)
{
EdgeEvent edgeEvent = e as EdgeEvent;
if (edgeEvent.LeftEdge == leftEdge && edgeEvent.RightEdge == rightEdge)
{
e.Invalidate();
}
}
}
events.Add(new EdgeEvent(intersection, arc, leftEdge, rightEdge));
events.Sort();
return(true);
}
}
}
return(false);
}
public List <BeachLineEdge> Squeeze(out BeachLineEdge newEdge)
{
// These are the output edges
BeachLineEdge leftEdge = (BeachLineEdge)Prev;
BeachLineEdge rightEdge = (BeachLineEdge)Next;
BeachLineArc leftArc = (BeachLineArc)leftEdge.Prev;
BeachLineArc rightArc = (BeachLineArc)rightEdge.Next;
// Create new edge
// To create it, we need the intersection point of the two output edges plus the
// focuses of the two arcs.
Vector2 intersection;
leftEdge.CheckIntersection(rightEdge, out intersection);
Vector2 focus1 = leftArc.Focus;
Vector2 focus2 = rightArc.Focus;
Vector2 perpendicular = focus2 - focus1;
Vector2 newEdgeDirection = new Vector2(perpendicular.y, -perpendicular.x);
if (Vector2.Dot(leftEdge.Direction.normalized + rightEdge.Direction.normalized, -newEdgeDirection) > 0)
//if (newEdgeDirection.y < 0)
{
newEdgeDirection = -newEdgeDirection;
}
newEdge = new BeachLineEdge(intersection, newEdgeDirection.normalized);
BeachLineEdge edgeToReplace = leftEdge == Parent ? rightEdge : leftEdge;
//newEdge.SetLeftArc(LeftArc);
//newEdge.SetRightArc(RightArc);
// Replace other edge with new edge
edgeToReplace.ReplaceWithSingleNode(newEdge);
// Replace parent with sibling
BeachLineElement sibling = Sibling;
sibling.SetParent(null);
bool iAmLeftChild = this == Parent.LeftChild;
if (iAmLeftChild)
{
Parent.SetRightChild(null);
}
else
{
Parent.SetLeftChild(null);
}
BeachLineElement parentsParent = Parent.Parent;
bool parentIsLeftChild = Parent == parentsParent.LeftChild;
if (parentIsLeftChild)
{
parentsParent.SetLeftChild(sibling);
}
else
{
parentsParent.SetRightChild(sibling);
}
sibling.SetParent(parentsParent);
//Parent.ReplaceWith(Sibling);
//Parent.SetLeftChild(null);
//Parent.SetRightChild(null);
// Set next/prev for altered nodes
leftArc.SetNext(newEdge);
newEdge.SetPrev(leftArc);
newEdge.SetNext(rightArc);
rightArc.SetPrev(newEdge);
// Remove this node from tree
SetParent(null);
SetLeftChild(null);
SetRightChild(null);
SetNext(null);
SetPrev(null);
leftEdge.SetParent(null);
leftEdge.SetLeftChild(null);
leftEdge.SetRightChild(null);
leftEdge.SetNext(null);
leftEdge.SetPrev(null);
rightEdge.SetParent(null);
rightEdge.SetLeftChild(null);
rightEdge.SetRightChild(null);
rightEdge.SetNext(null);
rightEdge.SetPrev(null);
leftEdge.SetEndpoint(intersection);
rightEdge.SetEndpoint(intersection);
List <BeachLineEdge> outputList = new List <BeachLineEdge>
{
leftEdge,
rightEdge
};
return(outputList);
}