private List <Node> FollowSegment(CountryLineSegment seg)
{
List <Node> result = new List <Node>();
Node trapezoidNode = SearchGraph.Search(seg);
Trapezoid currentTrapezoid = (Trapezoid)trapezoidNode.Value;
result.Add(trapezoidNode);
while (seg.Point2.x > currentTrapezoid.RightPoint.x)
{
if (seg.isAbove(currentTrapezoid.RightPoint) == 1)
{
// rightp is above segment
currentTrapezoid = currentTrapezoid.LowerRightNeighbor;
}
else
{
// rightp is below segment
currentTrapezoid = currentTrapezoid.UpperRightNeighbor;
}
if (currentTrapezoid == null || !(currentTrapezoid.AssocNode.Value is Trapezoid))
{
Debug.Log("This shouldn't happen... (trapezoid is null or linking is broken)");
break;
}
result.Add(currentTrapezoid.AssocNode);
}
return(result);
}
/// <summary>
/// Updates old trapezoids to new trapezoids cut by input segment.
/// Requires seg.Point1.x < seg.Point2.x and no intersections
/// </summary>
/// <param name="oldTrapezoids"></param>
/// <param name="seg"></param>
/// <returns></returns>
public List <Trapezoid> Update(ref List <Node> oldTrapezoids, CountryLineSegment seg)
{
List <Trapezoid> newTrapezoids = new List <Trapezoid>();
// trapezoids storing 'not fully computed' top and bottom trapezoids
Trapezoid top = null;
Trapezoid bottom = null;
if (oldTrapezoids.Count == 1)
{
// only one intersected trapezoid
Trapezoid old = (Trapezoid)oldTrapezoids[0].Value;
// temporary trapezoids
Trapezoid left = null;
Trapezoid right = null;
top = new Trapezoid(old.Top, seg, seg.Point1, seg.Point2, null, null, null, null);
bottom = new Trapezoid(seg, old.Bottom, seg.Point1, seg.Point2, null, null, null, null);
newTrapezoids.Add(top);
newTrapezoids.Add(bottom);
if (old.LeftPoint.x < seg.Point1.x)
{
// there exists a 'left' trapezoid
left = new Trapezoid(old.Top, old.Bottom, old.LeftPoint, seg.Point1, old.UpperLeftNeighbor, old.LowerLeftNeighbor, top, bottom);
top.UpperLeftNeighbor = left;
top.LowerLeftNeighbor = left;
bottom.UpperLeftNeighbor = left;
bottom.LowerLeftNeighbor = left;
// update old's neighbors
if (old.LowerLeftNeighbor != null)
{
if (old.LowerLeftNeighbor.UpperRightNeighbor == old)
{
old.LowerLeftNeighbor.UpperRightNeighbor = left;
}
if (old.LowerLeftNeighbor.LowerRightNeighbor == old)
{
old.LowerLeftNeighbor.LowerRightNeighbor = left;
}
}
if (old.UpperLeftNeighbor != null)
{
if (old.UpperLeftNeighbor.UpperRightNeighbor == old)
{
old.UpperLeftNeighbor.UpperRightNeighbor = left;
}
if (old.UpperLeftNeighbor.LowerRightNeighbor == old)
{
old.UpperLeftNeighbor.LowerRightNeighbor = left;
}
}
// add created trapezoid
newTrapezoids.Add(left);
}
else
{
// since we assume there are no two points with the same x,
// we know that seg starts on old.leftp now
if (old.Bottom.isAbove(seg.Point1) == 1 && old.Top.isAbove(seg.Point1) == -1)
{
// seg starts in 'middle'
top.UpperLeftNeighbor = old.UpperLeftNeighbor;
top.LowerLeftNeighbor = old.UpperLeftNeighbor;
bottom.UpperLeftNeighbor = old.LowerLeftNeighbor;
bottom.LowerLeftNeighbor = old.LowerLeftNeighbor;
// update old's neighbors
if (old.LowerLeftNeighbor != null)
{
if (old.LowerLeftNeighbor.UpperRightNeighbor == old)
{
old.LowerLeftNeighbor.UpperRightNeighbor = bottom;
}
if (old.LowerLeftNeighbor.LowerRightNeighbor == old)
{
old.LowerLeftNeighbor.LowerRightNeighbor = bottom;
}
}
if (old.UpperLeftNeighbor != null)
{
if (old.UpperLeftNeighbor.UpperRightNeighbor == old)
{
old.UpperLeftNeighbor.UpperRightNeighbor = top;
}
if (old.UpperLeftNeighbor.LowerRightNeighbor == old)
{
old.UpperLeftNeighbor.LowerRightNeighbor = top;
}
}
}
else if (old.Bottom.isAbove(seg.Point1) == 1)
{
// seg starts on 'old.top'
bottom.UpperLeftNeighbor = old.UpperLeftNeighbor;
bottom.LowerLeftNeighbor = old.LowerLeftNeighbor;
// update old's neighbors
if (old.LowerLeftNeighbor != null)
{
if (old.LowerLeftNeighbor.UpperRightNeighbor == old)
{
old.LowerLeftNeighbor.UpperRightNeighbor = bottom;
}
if (old.LowerLeftNeighbor.LowerRightNeighbor == old)
{
old.LowerLeftNeighbor.LowerRightNeighbor = bottom;
}
}
if (old.UpperLeftNeighbor != null)
{
if (old.UpperLeftNeighbor.UpperRightNeighbor == old)
{
old.UpperLeftNeighbor.UpperRightNeighbor = bottom;
}
if (old.UpperLeftNeighbor.LowerRightNeighbor == old)
{
old.UpperLeftNeighbor.LowerRightNeighbor = bottom;
}
}
}
else
{
// seg starts on 'old.bottom'
top.UpperLeftNeighbor = old.UpperLeftNeighbor;
top.LowerLeftNeighbor = old.LowerLeftNeighbor;
// update old's neighbors
if (old.LowerLeftNeighbor != null)
{
if (old.LowerLeftNeighbor.UpperRightNeighbor == old)
{
old.LowerLeftNeighbor.UpperRightNeighbor = top;
}
if (old.LowerLeftNeighbor.LowerRightNeighbor == old)
{
old.LowerLeftNeighbor.LowerRightNeighbor = top;
}
}
if (old.UpperLeftNeighbor != null)
{
if (old.UpperLeftNeighbor.UpperRightNeighbor == old)
{
old.UpperLeftNeighbor.UpperRightNeighbor = top;
}
if (old.UpperLeftNeighbor.LowerRightNeighbor == old)
{
old.UpperLeftNeighbor.LowerRightNeighbor = top;
}
}
}
}
if (seg.Point2.x < old.RightPoint.x)
{
// there exists a 'right' trapezoid
right = new Trapezoid(old.Top, old.Bottom, seg.Point2, old.RightPoint, top, bottom, old.UpperRightNeighbor, old.LowerRightNeighbor);
top.UpperRightNeighbor = right;
top.LowerRightNeighbor = right;
bottom.UpperRightNeighbor = right;
bottom.LowerRightNeighbor = right;
// update old's neighbors
if (old.LowerRightNeighbor != null)
{
if (old.LowerRightNeighbor.UpperLeftNeighbor == old)
{
old.LowerRightNeighbor.UpperLeftNeighbor = right;
}
if (old.LowerRightNeighbor.LowerLeftNeighbor == old)
{
old.LowerRightNeighbor.LowerLeftNeighbor = right;
}
}
if (old.UpperRightNeighbor != null)
{
if (old.UpperRightNeighbor.UpperLeftNeighbor == old)
{
old.UpperRightNeighbor.UpperLeftNeighbor = right;
}
if (old.UpperRightNeighbor.LowerLeftNeighbor == old)
{
old.UpperRightNeighbor.LowerLeftNeighbor = right;
}
}
if (old.LowerLeftNeighbor != null)
{
if (old.LowerLeftNeighbor.UpperRightNeighbor == old)
{
old.LowerLeftNeighbor.UpperRightNeighbor = right;
}
if (old.LowerLeftNeighbor.LowerRightNeighbor == old)
{
old.LowerLeftNeighbor.LowerRightNeighbor = right;
}
}
if (old.UpperLeftNeighbor != null)
{
if (old.UpperLeftNeighbor.UpperRightNeighbor == old)
{
old.UpperLeftNeighbor.UpperRightNeighbor = right;
}
if (old.UpperLeftNeighbor.LowerRightNeighbor == old)
{
old.UpperLeftNeighbor.LowerRightNeighbor = right;
}
}
// add created trapezoid
newTrapezoids.Add(right);
}
else
{
if (old.Bottom.isAbove(seg.Point2) == 1 && old.Top.isAbove(seg.Point2) == -1)
{
// seg ends in 'middle''
top.UpperRightNeighbor = old.UpperRightNeighbor;
top.LowerRightNeighbor = old.UpperRightNeighbor;
bottom.UpperRightNeighbor = old.LowerRightNeighbor;
bottom.LowerRightNeighbor = old.LowerRightNeighbor;
// update old's neighbors
if (old.LowerRightNeighbor != null)
{
old.LowerRightNeighbor.UpperLeftNeighbor = bottom;
old.LowerRightNeighbor.LowerLeftNeighbor = bottom;
}
if (old.UpperRightNeighbor != null)
{
old.UpperRightNeighbor.UpperLeftNeighbor = top;
old.UpperRightNeighbor.LowerLeftNeighbor = top;
}
}
else if (old.Bottom.isAbove(seg.Point2) == 1)
{
// seg ends on 'old.top'
bottom.UpperRightNeighbor = old.UpperRightNeighbor;
bottom.LowerRightNeighbor = old.LowerRightNeighbor;
// update old's neighbors
if (old.LowerRightNeighbor != null)
{
if (old.LowerRightNeighbor.UpperLeftNeighbor == old)
{
old.LowerRightNeighbor.UpperLeftNeighbor = bottom;
}
if (old.LowerRightNeighbor.LowerLeftNeighbor == old)
{
old.LowerRightNeighbor.LowerLeftNeighbor = bottom;
}
}
if (old.UpperRightNeighbor != null)
{
if (old.UpperRightNeighbor.UpperLeftNeighbor == old)
{
old.UpperRightNeighbor.UpperLeftNeighbor = bottom;
}
if (old.UpperRightNeighbor.LowerLeftNeighbor == old)
{
old.UpperRightNeighbor.LowerLeftNeighbor = bottom;
}
}
}
else
{
// seg ends on 'old.bottom'
top.UpperRightNeighbor = old.UpperRightNeighbor;
top.LowerRightNeighbor = old.LowerRightNeighbor;
// update old's neighbors
if (old.LowerRightNeighbor != null)
{
if (old.LowerRightNeighbor.UpperLeftNeighbor == old)
{
old.LowerRightNeighbor.UpperLeftNeighbor = top;
}
if (old.LowerRightNeighbor.LowerLeftNeighbor == old)
{
old.LowerRightNeighbor.LowerLeftNeighbor = top;
}
}
if (old.UpperRightNeighbor != null)
{
if (old.UpperRightNeighbor.UpperLeftNeighbor == old)
{
old.UpperRightNeighbor.UpperLeftNeighbor = top;
}
if (old.UpperRightNeighbor.LowerLeftNeighbor == old)
{
old.UpperRightNeighbor.LowerLeftNeighbor = top;
}
}
}
}
Node segNode = new Node(seg);
segNode.LeftChild = top.AssocNode;
segNode.RightChild = bottom.AssocNode;
if (left != null)
{
// replace trapezoid node by (left) segment point node
oldTrapezoids[0].Value = seg.Point1;
oldTrapezoids[0].LeftChild = left.AssocNode;
oldTrapezoids[0].RightChild = segNode;
}
if (right != null)
{
if (left != null)
{
// add appropriate children
oldTrapezoids[0].RightChild = new Node(seg.Point2)
{
LeftChild = segNode,
RightChild = right.AssocNode
};
}
else
{
oldTrapezoids[0].Value = seg.Point2;
oldTrapezoids[0].LeftChild = segNode;
oldTrapezoids[0].RightChild = right.AssocNode;
}
}
if (left == null && right == null)
{
oldTrapezoids[0].Value = seg;
oldTrapezoids[0].LeftChild = top.AssocNode;
oldTrapezoids[0].RightChild = bottom.AssocNode;
}
return(newTrapezoids);
}
for (int c = 0; c < oldTrapezoids.Count; c++)
{
if (c == 0)
{
// first trapezoid
Trapezoid old = (Trapezoid)oldTrapezoids[c].Value;
// temporary trapezoids
Trapezoid left = null;
top = new Trapezoid(old.Top, seg, seg.Point1, Vector2.one, null, null, null, null);
bottom = new Trapezoid(seg, old.Bottom, seg.Point1, Vector2.one, null, null, null, null);
newTrapezoids.Add(top);
newTrapezoids.Add(bottom);
if (old.LeftPoint.x < seg.Point1.x)
{
// there exists a 'left' trapezoid
left = new Trapezoid(old.Top, old.Bottom, old.LeftPoint, seg.Point1, old.UpperLeftNeighbor, old.LowerLeftNeighbor, top, bottom);
top.UpperLeftNeighbor = left;
top.LowerLeftNeighbor = left;
bottom.UpperLeftNeighbor = left;
bottom.LowerLeftNeighbor = left;
// update old's neighbors
if (old.LowerLeftNeighbor != null)
{
if (old.LowerLeftNeighbor.UpperRightNeighbor == old)
{
old.LowerLeftNeighbor.UpperRightNeighbor = left;
}
if (old.LowerLeftNeighbor.LowerRightNeighbor == old)
{
old.LowerLeftNeighbor.LowerRightNeighbor = left;
}
}
if (old.UpperLeftNeighbor != null)
{
if (old.UpperLeftNeighbor.UpperRightNeighbor == old)
{
old.UpperLeftNeighbor.UpperRightNeighbor = left;
}
if (old.UpperLeftNeighbor.LowerRightNeighbor == old)
{
old.UpperLeftNeighbor.LowerRightNeighbor = left;
}
}
// add created trapezoid
newTrapezoids.Add(left);
}
else
{
// since we assume there are no two points with the same x,
// we know that seg starts on old.leftp now
if (old.Bottom.isAbove(seg.Point1) == 1 && old.Top.isAbove(seg.Point1) == -1)
{
// seg starts in 'middle'
top.UpperLeftNeighbor = old.UpperLeftNeighbor;
top.LowerLeftNeighbor = old.UpperLeftNeighbor;
bottom.UpperLeftNeighbor = old.LowerLeftNeighbor;
bottom.LowerLeftNeighbor = old.LowerLeftNeighbor;
// update old's neighbors
if (old.LowerLeftNeighbor != null)
{
old.LowerLeftNeighbor.UpperRightNeighbor = bottom;
old.LowerLeftNeighbor.LowerRightNeighbor = bottom;
}
if (old.UpperLeftNeighbor != null)
{
old.UpperLeftNeighbor.UpperRightNeighbor = top;
old.UpperLeftNeighbor.LowerRightNeighbor = top;
}
}
else if (old.Bottom.isAbove(seg.Point1) == 1)
{
// seg starts on 'old.top'
bottom.UpperLeftNeighbor = old.UpperLeftNeighbor;
bottom.LowerLeftNeighbor = old.LowerLeftNeighbor;
// update old's neighbors
if (old.LowerLeftNeighbor != null)
{
if (old.LowerLeftNeighbor.UpperRightNeighbor == old)
{
old.LowerLeftNeighbor.UpperRightNeighbor = bottom;
}
if (old.LowerLeftNeighbor.LowerRightNeighbor == old)
{
old.LowerLeftNeighbor.LowerRightNeighbor = bottom;
}
}
if (old.UpperLeftNeighbor != null)
{
if (old.UpperLeftNeighbor.UpperRightNeighbor == old)
{
old.UpperLeftNeighbor.UpperRightNeighbor = bottom;
}
if (old.UpperLeftNeighbor.LowerRightNeighbor == old)
{
old.UpperLeftNeighbor.LowerRightNeighbor = bottom;
}
}
}
else
{
// seg starts on 'old.bottom'
top.UpperLeftNeighbor = old.UpperLeftNeighbor;
top.LowerLeftNeighbor = old.LowerLeftNeighbor;
// update old's neighbors
if (old.LowerLeftNeighbor != null)
{
if (old.LowerLeftNeighbor.UpperRightNeighbor == old)
{
old.LowerLeftNeighbor.UpperRightNeighbor = top;
}
if (old.LowerLeftNeighbor.LowerRightNeighbor == old)
{
old.LowerLeftNeighbor.LowerRightNeighbor = top;
}
}
if (old.UpperLeftNeighbor != null)
{
if (old.UpperLeftNeighbor.UpperRightNeighbor == old)
{
old.UpperLeftNeighbor.UpperRightNeighbor = top;
}
if (old.UpperLeftNeighbor.LowerRightNeighbor == old)
{
old.UpperLeftNeighbor.LowerRightNeighbor = top;
}
}
}
}
if (left != null)
{
// replace trapezoid node by (left) segment point node
Node segNode = new Node(seg)
{
LeftChild = top.AssocNode,
RightChild = bottom.AssocNode
};
oldTrapezoids[c].Value = seg.Point1;
oldTrapezoids[c].LeftChild = left.AssocNode;
oldTrapezoids[c].RightChild = segNode;
}
else
{
// replace trapezoid node by segment node
oldTrapezoids[c].Value = seg;
oldTrapezoids[c].LeftChild = top.AssocNode;
oldTrapezoids[c].RightChild = bottom.AssocNode;
}
}
else if (c == oldTrapezoids.Count - 1)
{
Trapezoid old = (Trapezoid)oldTrapezoids[c].Value;
Trapezoid right = null;
// 'finish' last top/bottom
if (seg.isAbove(old.LeftPoint) == 1)
{
// old leftp is above segment ==> 'top' is finished
Trapezoid newTop = new Trapezoid(old.Top, seg, old.LeftPoint, seg.Point2, top, top, null, null);
if (old.UpperLeftNeighbor != old.LowerLeftNeighbor)
{
newTop.UpperLeftNeighbor = old.UpperLeftNeighbor;
}
top.RightPoint = old.LeftPoint;
top.LowerRightNeighbor = newTop;
if (old.UpperLeftNeighbor.UpperRightNeighbor == old.UpperLeftNeighbor.LowerRightNeighbor)
{
top.UpperRightNeighbor = newTop;
// update old neighbors
old.UpperLeftNeighbor.UpperRightNeighbor = newTop;
old.UpperLeftNeighbor.LowerRightNeighbor = newTop;
}
else
{
// account for splitting into 'lower' trapezoid
top.UpperRightNeighbor = old.UpperLeftNeighbor.UpperRightNeighbor;
old.LowerLeftNeighbor.UpperRightNeighbor.UpperLeftNeighbor = top;
old.LowerLeftNeighbor.UpperRightNeighbor.LowerLeftNeighbor = top;
}
// add new top
top = newTop;
newTrapezoids.Add(top);
// end trapezoid, so add rightp to 'bottom'
bottom.RightPoint = seg.Point2;
}
else
{
// old leftp is below segment ==> 'bottom' is finished
Trapezoid newBottom = new Trapezoid(seg, old.Bottom, old.LeftPoint, seg.Point2, bottom, bottom, null, null);
if (old.UpperLeftNeighbor != old.LowerLeftNeighbor)
{
newBottom.LowerLeftNeighbor = old.LowerLeftNeighbor;
}
bottom.RightPoint = old.LeftPoint;
bottom.UpperRightNeighbor = newBottom;
if (old.LowerLeftNeighbor.LowerRightNeighbor == old.LowerLeftNeighbor.UpperRightNeighbor)
{
bottom.LowerRightNeighbor = newBottom;
// update old neighbors
old.LowerLeftNeighbor.LowerRightNeighbor = newBottom;
old.LowerLeftNeighbor.UpperRightNeighbor = newBottom;
}
else
{
// account for splitting into 'higher' trapezoid
bottom.LowerRightNeighbor = old.LowerLeftNeighbor.LowerRightNeighbor;
old.LowerLeftNeighbor.LowerRightNeighbor.UpperLeftNeighbor = bottom;
old.LowerLeftNeighbor.LowerRightNeighbor.LowerLeftNeighbor = bottom;
}
// add new bottom
bottom = newBottom;
newTrapezoids.Add(bottom);
// end trapezoid, so add rightp to 'top'
top.RightPoint = seg.Point2;
}
// last trapezoid
if (seg.Point2.x < old.RightPoint.x)
{
// there exists a 'right' trapezoid
right = new Trapezoid(old.Top, old.Bottom, seg.Point2, old.RightPoint, top, bottom, old.UpperRightNeighbor, old.LowerRightNeighbor);
top.UpperRightNeighbor = right;
top.LowerRightNeighbor = right;
bottom.UpperRightNeighbor = right;
bottom.LowerRightNeighbor = right;
// update old's neighbors
if (old.LowerRightNeighbor != null)
{
if (old.LowerRightNeighbor.UpperLeftNeighbor == old)
{
old.LowerRightNeighbor.UpperLeftNeighbor = right;
}
if (old.LowerRightNeighbor.LowerLeftNeighbor == old)
{
old.LowerRightNeighbor.LowerLeftNeighbor = right;
}
}
if (old.UpperRightNeighbor != null)
{
if (old.UpperRightNeighbor.UpperLeftNeighbor == old)
{
old.UpperRightNeighbor.UpperLeftNeighbor = right;
}
if (old.UpperRightNeighbor.LowerLeftNeighbor == old)
{
old.UpperRightNeighbor.LowerLeftNeighbor = right;
}
}
if (old.LowerLeftNeighbor != null)
{
if (old.LowerLeftNeighbor.UpperRightNeighbor == old)
{
old.LowerLeftNeighbor.UpperRightNeighbor = right;
}
if (old.LowerLeftNeighbor.LowerRightNeighbor == old)
{
old.LowerLeftNeighbor.LowerRightNeighbor = right;
}
}
if (old.UpperLeftNeighbor != null)
{
if (old.UpperLeftNeighbor.UpperRightNeighbor == old)
{
old.UpperLeftNeighbor.UpperRightNeighbor = right;
}
if (old.UpperLeftNeighbor.LowerRightNeighbor == old)
{
old.UpperLeftNeighbor.LowerRightNeighbor = right;
}
}
// add created trapezoid
newTrapezoids.Add(right);
}
else
{
if (old.Bottom.isAbove(seg.Point2) == 1 && old.Top.isAbove(seg.Point2) == -1)
{
// seg ends in 'middle''
top.UpperRightNeighbor = old.UpperRightNeighbor;
top.LowerRightNeighbor = old.UpperRightNeighbor;
bottom.UpperRightNeighbor = old.LowerRightNeighbor;
bottom.LowerRightNeighbor = old.LowerRightNeighbor;
// update old's neighbors
if (old.LowerRightNeighbor != null)
{
if (old.LowerRightNeighbor.UpperLeftNeighbor == old)
{
old.LowerRightNeighbor.UpperLeftNeighbor = bottom;
}
if (old.LowerRightNeighbor.LowerLeftNeighbor == old)
{
old.LowerRightNeighbor.LowerLeftNeighbor = bottom;
}
}
if (old.UpperRightNeighbor != null)
{
if (old.UpperRightNeighbor.UpperLeftNeighbor == old)
{
old.UpperRightNeighbor.UpperLeftNeighbor = top;
}
if (old.UpperRightNeighbor.LowerLeftNeighbor == old)
{
old.UpperRightNeighbor.LowerLeftNeighbor = top;
}
}
}
else if (old.Bottom.isAbove(seg.Point2) == 1)
{
// seg ends on 'old.top'
bottom.UpperRightNeighbor = old.UpperRightNeighbor;
bottom.LowerRightNeighbor = old.LowerRightNeighbor;
// update old's neighbors
if (old.LowerRightNeighbor != null)
{
if (old.LowerRightNeighbor.UpperLeftNeighbor == old)
{
old.LowerRightNeighbor.UpperLeftNeighbor = bottom;
}
if (old.LowerRightNeighbor.LowerLeftNeighbor == old)
{
old.LowerRightNeighbor.LowerLeftNeighbor = bottom;
}
}
if (old.UpperRightNeighbor != null)
{
if (old.UpperRightNeighbor.UpperLeftNeighbor == old)
{
old.UpperRightNeighbor.UpperLeftNeighbor = bottom;
}
if (old.UpperRightNeighbor.LowerLeftNeighbor == old)
{
old.UpperRightNeighbor.LowerLeftNeighbor = bottom;
}
}
}
else
{
// seg ends on 'old.bottom'
top.UpperRightNeighbor = old.UpperRightNeighbor;
top.LowerRightNeighbor = old.LowerRightNeighbor;
// update old's neighbors
if (old.LowerRightNeighbor != null)
{
if (old.LowerRightNeighbor.UpperLeftNeighbor == old)
{
old.LowerRightNeighbor.UpperLeftNeighbor = top;
}
if (old.LowerRightNeighbor.LowerLeftNeighbor == old)
{
old.LowerRightNeighbor.LowerLeftNeighbor = top;
}
}
if (old.UpperRightNeighbor != null)
{
if (old.UpperRightNeighbor.UpperLeftNeighbor == old)
{
old.UpperRightNeighbor.UpperLeftNeighbor = top;
}
if (old.UpperRightNeighbor.LowerLeftNeighbor == old)
{
old.UpperRightNeighbor.LowerLeftNeighbor = top;
}
}
}
}
if (right != null)
{
// replace trapezoid node by (right) segment point node
Node segNode = new Node(seg)
{
LeftChild = top.AssocNode,
RightChild = bottom.AssocNode
};
oldTrapezoids[c].Value = seg.Point2;
oldTrapezoids[c].LeftChild = segNode;
oldTrapezoids[c].RightChild = right.AssocNode;
}
else
{
oldTrapezoids[c].Value = seg;
oldTrapezoids[c].LeftChild = top.AssocNode;
oldTrapezoids[c].RightChild = bottom.AssocNode;
}
}
else
{
// intermediary trapezoid
Trapezoid old = (Trapezoid)oldTrapezoids[c].Value;
// 'finish' last top/bottom
if (seg.isAbove(old.LeftPoint) == 1)
{
// old leftp is above segment ==> 'top' is finished
Trapezoid newTop = new Trapezoid(old.Top, seg, old.LeftPoint, Vector2.one, top, top, null, null);
if (old.UpperLeftNeighbor != old.LowerLeftNeighbor)
{
newTop.UpperLeftNeighbor = old.UpperLeftNeighbor;
}
top.RightPoint = old.LeftPoint;
top.LowerRightNeighbor = newTop;
if (old.UpperLeftNeighbor.UpperRightNeighbor == old.UpperLeftNeighbor.LowerRightNeighbor)
{
top.UpperRightNeighbor = newTop;
// update old neighbors
old.UpperLeftNeighbor.UpperRightNeighbor = newTop;
old.UpperLeftNeighbor.LowerRightNeighbor = newTop;
}
else
{
// account for splitting into 'lower' trapezoid
top.UpperRightNeighbor = old.UpperLeftNeighbor.UpperRightNeighbor;
old.LowerLeftNeighbor.UpperRightNeighbor.UpperLeftNeighbor = top;
old.LowerLeftNeighbor.UpperRightNeighbor.LowerLeftNeighbor = top;
}
// add new top
top = newTop;
newTrapezoids.Add(top);
}
else
{
// old leftp is below segment ==> 'bottom' is finished
Trapezoid newBottom = new Trapezoid(seg, old.Bottom, old.LeftPoint, Vector2.one, bottom, bottom, null, null);
if (old.UpperLeftNeighbor != old.LowerLeftNeighbor)
{
newBottom.LowerLeftNeighbor = old.LowerLeftNeighbor;
}
bottom.RightPoint = old.LeftPoint;
bottom.UpperRightNeighbor = newBottom;
if (old.LowerLeftNeighbor.LowerRightNeighbor == old.LowerLeftNeighbor.UpperRightNeighbor)
{
bottom.LowerRightNeighbor = newBottom;
old.LowerLeftNeighbor.LowerRightNeighbor = newBottom;
old.LowerLeftNeighbor.UpperRightNeighbor = newBottom;
}
else
{
// account for splitting into 'higher' trapezoid
bottom.LowerRightNeighbor = old.LowerLeftNeighbor.LowerRightNeighbor;
old.LowerLeftNeighbor.LowerRightNeighbor.UpperLeftNeighbor = bottom;
old.LowerLeftNeighbor.LowerRightNeighbor.LowerLeftNeighbor = bottom;
}
// add new bottom
bottom = newBottom;
newTrapezoids.Add(bottom);
}
// add seg node to tree
oldTrapezoids[c].Value = seg;
oldTrapezoids[c].LeftChild = top.AssocNode;
oldTrapezoids[c].RightChild = bottom.AssocNode;
}
}
return(newTrapezoids);
}