public void DeleteTest()
{
CreateTree();
Assert.IsTrue(m_tree.Delete(5));
Assert.IsTrue(m_tree.Delete(-999));
Assert.IsFalse(m_tree.Delete(5));
Assert.IsTrue(m_tree.Delete(0));
Assert.IsFalse(m_tree.Delete(0));
}
public static void Main()
{
var tree = new AATree<int>();
Console.WriteLine("The AA tree created.");
var nums = new[] { -5, 20, 14, 11, 8, -3, 111, 7, 100, -55 };
for (int i = 0; i < nums.Length; i++)
{
AddNumber(tree, nums[i]);
}
Console.WriteLine("\n\nTree after we remove element:\n");
tree.Delete(14, tree.Root);
DisplayTree(tree.Root, string.Empty);
}
public static Polygon2D Vision(Polygon2DWithHoles polygon, Vector2 x)
{
if (!(polygon.ContainsInside(x) || polygon.OnBoundary(x)))
{
throw new ArgumentException(x + " is not inside polygon: " + polygon);
}
float initAngle;
var events = Preprocess(polygon, x, out initAngle);
var status = new AATree <StatusItem>();
var visibility = new List <Vector2>();
// create ray in positive x direction
var ray = new Ray2D(Vector2.zero, new Vector2(1f, 0f));
VisibilityEvent xEvent = null;
// initialize the status
foreach (var v in events)
{
if (MathUtil.EqualsEps(v.vertex, Vector2.zero))
{
xEvent = v;
continue;
}
var seg = v.item1.seg;
if (!seg.IsEndpoint(x))
{
var intersect = seg.Intersect(ray);
if (intersect.HasValue && intersect.Value.x > 0 && (seg.Point1.y >= 0 != seg.Point2.y >= 0) &&
!MathUtil.EqualsEps(intersect.Value, Vector2.zero))
{
status.Insert(v.item1);
}
}
}
if (xEvent != null)
{
if (!xEvent.isHole)
{
status.Insert(xEvent.item1);
}
else
{
status.Delete(xEvent.item1);
}
if (!xEvent.isHole)
{
status.Delete(xEvent.item2);
}
else
{
status.Insert(xEvent.item2);
}
if (!xEvent.isHole)
{
visibility.Add(xEvent.item2.seg.Point2);
visibility.Add(Vector2.zero);
visibility.Add(xEvent.item1.seg.Point1);
}
else
{
visibility.Add(xEvent.item2.seg.Point1);
visibility.Add(Vector2.zero);
visibility.Add(xEvent.item1.seg.Point2);
}
}
// handle events
StatusItem top = null;
var insertions = new HashSet <StatusItem>();
if (status.Count > 0)
{
status.FindMin(out top);
}
for (var i = 0; i < events.Count; i++)
{
var v = events[i];
if (MathUtil.EqualsEps(v.vertex, Vector2.zero))
{
continue;
}
ray = new Ray2D(Vector2.zero, v.vertex);
// first handle deletions
// handle first segment
if (status.Contains(v.item1))
{
status.Delete(v.item1);
}
else if (insertions.Contains(v.item1))
{
insertions.Remove(v.item1);
}
else
{
insertions.Add(v.item1);
}
// handle second segment
if (status.Contains(v.item2))
{
status.Delete(v.item2);
}
else if (insertions.Contains(v.item2))
{
insertions.Remove(v.item2);
}
else
{
insertions.Add(v.item2);
}
// skip if next event colinear with current
if (i < events.Count - 1 && Line.Colinear(Vector2.zero, v.vertex, events[i + 1].vertex))
{
// skip until all colinear events are handled
continue;
}
// handle insertions (after potential skip for colinear events
foreach (var item in insertions)
{
status.Insert(item);
}
insertions.Clear();
StatusItem newTop;
status.FindMin(out newTop);
// do stuff if current top different from previous
if (top != newTop)
{
// add intersections with previous top segment
if (top != null)
{
HandleTopSegment(ref visibility, top.seg, ray);
}
// add intersections with new top segment
if (newTop != null)
{
HandleTopSegment(ref visibility, newTop.seg, ray);
}
top = newTop;
}
}
return(Postprocess(visibility, x, initAngle));
}
