public void TestRemoveLeaf()
{
var beachLine = new BeachLine(0);
var site1 = new Point {
X = 40, Y = 60
};
var site2 = new Point {
X = 20, Y = 40
};
var site3 = new Point {
X = 60, Y = 40
};
beachLine.InsertSite(site1);
beachLine.InsertSite(site2);
var insert = beachLine.InsertSite(site3);
var circleEvents = beachLine.GenerateCircleEvent(insert.Leaves, site3.Y);
var circleEvent = circleEvents.Single();
beachLine.RemoveLeaf(circleEvent.Arc);
var rightSubtree = ((Node)beachLine.Root).Right as Node;
var leafLeft = rightSubtree.Left as Leaf;
var leafRight = rightSubtree.Right as Leaf;
Assert.IsNotNull(leafLeft);
Assert.IsNotNull(leafRight);
Assert.AreEqual(rightSubtree.Breakpoint.Left, site3);
Assert.AreEqual(rightSubtree.Breakpoint.Right, site1);
Assert.AreEqual(leafLeft.Site, site3);
Assert.AreEqual(leafRight.Site, site1);
}
public ICollection <IGeometry> HandleEvent(CircleEvent sweepEvent, EventQueue eventQueue, BeachLine beachLine)
{
if (sweepEvent.Arc.Parent == null)
{
throw new InvalidOperationException($"CircleEvent: Arc {sweepEvent.Arc.Site}: Parent of node {0} is null");
}
var leftParent = sweepEvent.Arc.GetParent(TraverseDirection.CounterClockwise);
var rightParent = sweepEvent.Arc.GetParent(TraverseDirection.Clockwise);
var left = leftParent?.GetLeaf(TraverseDirection.CounterClockwise);
var right = rightParent?.GetLeaf(TraverseDirection.Clockwise);
if (left == null || right == null)
{
throw new InvalidOperationException($"Neighbor of node {sweepEvent.Arc.Site} is null.");
}
if (left.CircleEvent != null)
{
eventQueue.Remove(left.CircleEvent);
left.CircleEvent = null;
}
if (right.CircleEvent != null)
{
eventQueue.Remove(right.CircleEvent);
right.CircleEvent = null;
}
var p = new Point(sweepEvent.Point.X, _calculationService.GetY(sweepEvent.Arc.Site, sweepEvent.Point));
leftParent.HalfEdge.EndPoint = p;
rightParent.HalfEdge.EndPoint = p;
var vertex = new Vertex {
Point = p
};
ConnectHalfEdgeWithVertex(leftParent.HalfEdge, vertex, (e, v) => e.End = v);
ConnectHalfEdgeWithVertex(rightParent.HalfEdge, vertex, (e, v) => e.End = v);
// Add third half edge
var halfEdge = new HalfEdge(p, left.Site, right.Site);
ConnectHalfEdgeWithVertex(halfEdge, vertex, (e, v) => e.Start = v);
Logger.Instance.Log($"Left parent: {leftParent.HalfEdge}");
Logger.Instance.Log($"Right parent: {rightParent.HalfEdge}");
var higher = sweepEvent.Arc.GetFirstParent(leftParent, rightParent);
Logger.Instance.Log($"Higher node: {higher}");
Logger.Instance.Log($"Higher edge old: {higher.HalfEdge}");
higher.HalfEdge = halfEdge;
if (vertex.HalfEdges.Count != 3)
{
var message = $"Halfedge {halfEdge} is already connected to Vertex {vertex}";
Logger.Instance.Log(message);
Logger.Instance.ToFile();
throw new InvalidOperationException(message);
}
Logger.Instance.Log($"CircleEvent: Remove Arc {sweepEvent.Arc.Site}");
beachLine.RemoveLeaf(sweepEvent.Arc);
var circleEvents = beachLine.GenerateCircleEvent(new[] { left, right }, sweepEvent.Point.Y);
eventQueue.Insert(circleEvents);
return(new List <IGeometry> {
vertex, halfEdge
});
}