/// <summary>
/// Internal helper function for computing intersections.
/// </summary>
private static bool IntersectHorizontal(ref RCNumRectangle lRect, ref RCNumRectangle rRect, out RCNumber intersectLeft, out RCNumber intersectRight)
{
if ((lRect.Left <= rRect.Left && rRect.Left < lRect.Right && lRect.Right <= rRect.Right))
{
intersectLeft = rRect.Left;
intersectRight = lRect.Right;
return(true);
}
else if (rRect.Left <= lRect.Left && lRect.Left < lRect.Right && lRect.Right <= rRect.Right)
{
intersectLeft = lRect.Left;
intersectRight = lRect.Right;
return(true);
}
else if (rRect.Left <= lRect.Left && lRect.Left < rRect.Right && rRect.Right <= lRect.Right)
{
intersectLeft = lRect.Left;
intersectRight = rRect.Right;
return(true);
}
else
{
intersectLeft = 0;
intersectRight = 0;
return(false);
}
}
/// <summary>
/// Internal helper function for computing intersections.
/// </summary>
private static bool IntersectVertical(ref RCNumRectangle lRect, ref RCNumRectangle rRect, out RCNumber intersectTop, out RCNumber intersectBottom)
{
if (lRect.Top <= rRect.Top && rRect.Top < lRect.Bottom && lRect.Bottom <= rRect.Bottom)
{
intersectTop = rRect.Top;
intersectBottom = lRect.Bottom;
return(true);
}
else if (rRect.Top <= lRect.Top && lRect.Top < lRect.Bottom && lRect.Bottom <= rRect.Bottom)
{
intersectTop = lRect.Top;
intersectBottom = lRect.Bottom;
return(true);
}
else if (rRect.Top <= lRect.Top && lRect.Top < rRect.Bottom && rRect.Bottom <= lRect.Bottom)
{
intersectTop = lRect.Top;
intersectBottom = rRect.Bottom;
return(true);
}
else
{
intersectTop = 0;
intersectBottom = 0;
return(false);
}
}
/// <summary>
/// Subdivides this BspSearchTreeNode if necessary.
/// </summary>
/// <remarks>Subdivision is only allowed in case of leaf-nodes.</remarks>
private void Subdivide()
{
if (!this.isLeaf)
{
throw new InvalidOperationException("Only leaf-nodes can be subdivided!");
}
this.isLeaf = false;
if (this.firstChild == null || this.secondChild == null)
{
/// Children have to be created.
RCNumRectangle firstChildArea = this.area.Width > this.area.Height
? new RCNumRectangle(this.area.X, this.area.Y, this.area.Width / 2, this.area.Height)
: new RCNumRectangle(this.area.X, this.area.Y, this.area.Width, this.area.Height / 2);
RCNumRectangle secondChildArea = this.area.Width > this.area.Height
? firstChildArea + new RCNumVector(firstChildArea.Width, 0)
: firstChildArea + new RCNumVector(0, firstChildArea.Height);
this.firstChild = new BspSearchTreeNode <T>(firstChildArea, this.capacity, this.minSize);
this.secondChild = new BspSearchTreeNode <T>(secondChildArea, this.capacity, this.minSize);
}
else
{
/// Children already exist.
this.firstChild.isLeaf = true;
this.secondChild.isLeaf = true;
this.firstChild.contents.Clear();
this.secondChild.contents.Clear();
}
}
/// <summary>
/// Returns a third RCNumRectangle that represents the intersection of two other RCRectangles.
/// If there is no intersection, RCNumRectangle.Undefined is returned.
/// </summary>
/// <param name="lRect">An RCNumRectangle to intersect.</param>
/// <param name="rRect">An RCNumRectangle to intersect.</param>
/// <returns>
/// An RCNumRectangle that is the intersection of lRect and rRect or RCNumRectangle.Undefined if there is no intersection.
/// </returns>
public static RCNumRectangle Intersect(RCNumRectangle lRect, RCNumRectangle rRect)
{
if (!lRect.isDefined)
{
throw new ArgumentNullException("lRect");
}
if (!rRect.isDefined)
{
throw new ArgumentNullException("rRect");
}
RCNumber intersectLeft, intersectRight, intersectTop, intersectBottom;
/// Compute the horizontal coordinates of the intersection
if (!IntersectHorizontal(ref lRect, ref rRect, out intersectLeft, out intersectRight) &&
!IntersectHorizontal(ref rRect, ref lRect, out intersectLeft, out intersectRight))
{
return(RCNumRectangle.Undefined);
}
/// Compute the vertical coordinates of the intersection
if (!IntersectVertical(ref lRect, ref rRect, out intersectTop, out intersectBottom) &&
!IntersectVertical(ref rRect, ref lRect, out intersectTop, out intersectBottom))
{
return(RCNumRectangle.Undefined);
}
return(new RCNumRectangle(intersectLeft, intersectTop, intersectRight - intersectLeft, intersectBottom - intersectTop));
}
/// <summary>
/// Collects every content attached to this BspSearchTreeNode inside the given rectangular area.
/// </summary>
/// <param name="area">The rectangular area.</param>
/// <param name="outputList">
/// A list that contains every content attached to this BspSearchTreeNode inside the given rectangular area.
/// </param>
public void CollectContents(RCNumRectangle area, ref RCSet <T> outputList)
{
if (this.isLeaf)
{
/// Leaf node -> collect the contents inside the given selection box.
foreach (T content in this.contents)
{
if (content.BoundingBox.IntersectsWith(area))
{
outputList.Add(content);
}
}
}
else
{
/// Not a leaf node -> propagate the call to the appropriate child(ren).
if (this.firstChild.area.IntersectsWith(area))
{
this.firstChild.CollectContents(area, ref outputList);
}
if (this.secondChild.area.IntersectsWith(area))
{
this.secondChild.CollectContents(area, ref outputList);
}
}
}
/// <summary>
/// Constructs a BspSearchTreeNode instance.
/// </summary>
/// <param name="area">The rectangular area covered by this BspSearchTreeNode.</param>
/// <param name="capacity">The maximum number of contents this node can hold without subdivision.</param>
/// <param name="minSize">The minimum size of a BSP-node.</param>
public BspSearchTreeNode(RCNumRectangle area, int capacity, int minSize)
{
this.contents = new RCSet <T>();
this.isLeaf = true;
this.capacity = capacity;
this.minSize = minSize;
this.area = area;
this.firstChild = null;
this.secondChild = null;
}
/// <see cref="ISearchTree<T>.GetContents"/>
public RCSet <T> GetContents(RCNumRectangle area)
{
if (area == RCNumRectangle.Undefined)
{
throw new ArgumentNullException("area");
}
RCSet <T> retList = new RCSet <T>();
this.rootNode.CollectContents(area, ref retList);
return(retList);
}
/// <summary>
/// Replaces this RCNumRectangle with the intersection of itself and the specified Rectangle.
/// </summary>
/// <param name="other">The other RCNumRectangle to intersect with.</param>
/// <remarks>
/// If this and other RCRectangles don't intersect each other, then this RCNumRectangle becomes RCNumRectangle.Undefined.
/// </remarks>
public void Intersect(RCNumRectangle other)
{
if (!this.isDefined)
{
throw new InvalidOperationException("Illegal use of undefined RCNumRectangle!");
}
if (!other.isDefined)
{
throw new ArgumentNullException("other");
}
this = RCNumRectangle.Intersect(this, other);
}
/// <summary>
/// Determines if this RCNumRectangle intersects with rect.
/// </summary>
/// <param name="rect">The RCNumRectangle to test.</param>
/// <returns>True if there is any intersection, false otherwise.</returns>
public bool IntersectsWith(RCNumRectangle rect)
{
if (!this.isDefined)
{
throw new InvalidOperationException("Illegal use of undefined RCNumRectangle!");
}
if (!rect.isDefined)
{
throw new ArgumentNullException("rect");
}
return((this.Left < rect.Right) && (this.Right > rect.Left) && (this.Top < rect.Bottom) && (this.Bottom > rect.Top));
}
/// <summary>
/// Initializes a new RCNumRectangle with the specified RCNumRectangle.
/// </summary>
/// <param name="other">The RCNumRectangle to initialize with.</param>
public RCNumRectangle(RCNumRectangle other)
{
if (!other.isDefined)
{
throw new ArgumentNullException("other");
}
this.isDefined = true;
this.x = other.x;
this.y = other.y;
this.width = other.width;
this.height = other.height;
}
/// <summary>
/// Determines if the rectangular region represented by rect is entirely contained within this RCNumRectangle.
/// </summary>
/// <param name="rect">The RCNumRectangle to test.</param>
/// <returns>True if the rectangular region represented by rect is entirely contained within this RCNumRectangle, false otherwise.</returns>
public bool Contains(RCNumRectangle rect)
{
if (!this.isDefined)
{
throw new InvalidOperationException("Illegal use of undefined RCNumRectangle!");
}
if (!rect.isDefined)
{
throw new ArgumentNullException("rect");
}
return(this.Contains(rect.x, rect.y) &&
this.Contains(rect.x + rect.width - new RCNumber(1), rect.y + rect.height - new RCNumber(1)));
}
/// <summary>
/// Constructs a BspSearchTree instance.
/// </summary>
/// <param name="area">The rectangular area covered by this search tree.</param>
/// <param name="nodeCapacity">The maximum number of contents a BSP-tree node can hold without subdivision.</param>
/// <param name="minNodeSize">The minimum size of a BSP-node.</param>
public BspSearchTree(RCNumRectangle area, int nodeCapacity, int minNodeSize)
{
if (area == RCNumRectangle.Undefined)
{
throw new ArgumentNullException("area");
}
if (nodeCapacity <= 0)
{
throw new ArgumentOutOfRangeException("nodeCapacity", "Node capacity must be greater than 0!");
}
if (minNodeSize <= 0)
{
throw new ArgumentOutOfRangeException("minNodeSize", "Minimum BSP-node size must be positive!");
}
this.attachedContents = new RCSet <T>();
this.rootNode = new BspSearchTreeNode <T>(area, nodeCapacity, minNodeSize);
}
/// <summary>
/// Checks whether this RCNumRectangle has the same location and size as the specified RCNumRectangle.
/// </summary>
/// <param name="other">The RCNumRectangle to test.</param>
/// <returns>True if other RCNumRectangle has same location and size as this RCNumRectangle.</returns>
public bool Equals(RCNumRectangle other)
{
return((!this.isDefined && !other.isDefined) ||
(this.isDefined && other.isDefined && this.x == other.x && this.y == other.y &&
this.width == other.width && this.height == other.height));
}
