public void Split(BeachLineArc newArc)
{
float splitX = newArc.Focus.x;
float sweepLine = newArc.Focus.y;
BeachLineArc newLeftArc = new BeachLineArc(this);
BeachLineArc newRightArc = new BeachLineArc(this);
Vector2 splitPoint = new Vector2(splitX, y(splitX));
Vector2 edgeDirection = Tangent(splitX);
// Make edgeDirection always point in the positive x direction
edgeDirection = edgeDirection.x < 0 ? -edgeDirection : edgeDirection;
BeachLineEdge newLeftEdge = new BeachLineEdge(splitPoint, -edgeDirection);
BeachLineEdge newRightEdge = new BeachLineEdge(splitPoint, edgeDirection);
newLeftEdge.SetLeftChild(newLeftArc);
newLeftEdge.SetRightChild(newRightEdge);
newLeftEdge.SetParent(Parent);
newRightEdge.SetLeftChild(newArc);
newRightEdge.SetRightChild(newRightArc);
newRightEdge.SetParent(newLeftEdge);
newLeftArc.SetParent(newLeftEdge);
newRightArc.SetParent(newRightEdge);
newArc.SetParent(newRightEdge);
// Change next and prev links
BeachLineEdge prevEdge = (BeachLineEdge)Prev;
BeachLineEdge nextEdge = (BeachLineEdge)Next;
LinkRemove();
if (prevEdge != null)
{
prevEdge.LinkInsertAfter(newLeftArc);
}
else
{
// newLeftArc is going to be the new start of the list
if (nextEdge != null)
{
newLeftArc.SetNext(nextEdge);
nextEdge.SetPrev(newLeftArc);
}
}
newLeftArc.LinkInsertAfter(newLeftEdge)
.LinkInsertAfter(newArc)
.LinkInsertAfter(newRightEdge)
.LinkInsertAfter(newRightArc);
//if (nextEdge != null)
//{
// newRightArc.SetNext(nextEdge);
// nextEdge.SetPrev(newRightArc);
//}
BeachLineElement parent = Parent;
if (parent == null)
{
// This is root. Replace this with left edge.
BeachLineRoot.SetRoot(newLeftEdge);
}
else
{
// Set parent to point to new construct
if (parent.LeftChild == this)
{
parent.SetLeftChild(newLeftEdge);
}
else if (parent.RightChild == this)
{
parent.SetRightChild(newLeftEdge);
}
else
{
Debug.LogError("Error in Split - couldn't find child in parent.");
}
}
// We can now remove this node
//SetLeftArc(null);
//SetRightArc(null);
//SetLeftEdge(null);
//SetRightEdge(null);
SetLeftChild(null);
SetRightChild(null);
SetParent(null);
}
// Use this for initialization
void Start()
{
leftArc.LinkInsertAfter(leftEdge).LinkInsertAfter(newArc).LinkInsertAfter(rightEdge).LinkInsertAfter(rightArc);
}