public void ReplaceWithSingleNode(BeachLineElement newNode)
{
if (Parent != null)
{
newNode.SetParent(Parent);
if (Parent.LeftChild == this)
{
Parent.SetLeftChild(newNode);
}
else
{
Parent.SetRightChild(newNode);
}
}
else
{
// This is the root node
mBeachLine.SetRoot(newNode);
}
if (LeftChild != null)
{
newNode.SetLeftChild(LeftChild);
LeftChild.SetParent(newNode);
}
if (RightChild != null)
{
newNode.SetRightChild(RightChild);
RightChild.SetParent(newNode);
}
mParent = null;
mLeftChild = null;
mRightChild = null;
}
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);
}
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);
}