/// <summary>
/// Tests whether this node contains a rectangle
/// </summary>
/// <param name="rect">The rectangle to test</param>
/// <returns>Whether or not this node contains the specified rectangle</returns>
public bool ContainsRect(FRect rect)
{
return(rect.TopLeft.X >= Rect.TopLeft.X &&
rect.TopLeft.Y >= Rect.TopLeft.Y &&
rect.BottomRight.X <= Rect.BottomRight.X &&
rect.BottomRight.Y <= Rect.BottomRight.Y);
}
/// <summary>
/// Gets a list of items intersecting a specified rectangle
/// </summary>
/// <param name="Rect">The rectangle</param>
/// <param name="ItemsFound">The list to add found items to (list will not be cleared first)</param>
public void GetItems(FRect Rect, ref List <QuadTreePositionItem <T> > ItemsList)
{
if (ItemsList != null)
{
headNode.GetItems(Rect, ref ItemsList);
}
}
/// <summary>
/// Checks if this rectangle intersects another rectangle
/// </summary>
/// <param name="Rect">The rectangle to check</param>
/// <returns>Whether or not this rectangle intersects the other</returns>
public bool Intersects(FRect Rect)
{
return(!(Bottom < Rect.Top ||
Top > Rect.Bottom ||
Right < Rect.Left ||
Left > Rect.Right));
}
/// <summary>
/// QuadTreeNode constructor
/// </summary>
/// <param name="parentNode">The parent node of this QuadTreeNode</param>
/// <param name="rect">The rectangle of the QuadTreeNode</param>
/// <param name="maxItems">Maximum number of items in the QuadTreeNode before partitioning</param>
public QuadTreeNode(QuadTreeNode <T> parentNode, FRect rect, int maxItems)
{
ParentNode = parentNode;
Rect = rect;
MaxItems = maxItems;
IsPartitioned = false;
Items = new List <QuadTreePositionItem <T> >();
}
/// <summary>
/// QuadTreeNode constructor
/// </summary>
/// <param name="rect">The rectangle of the QuadTreeNode</param>
/// <param name="maxItems">Maximum number of items in the QuadTreeNode before partitioning</param>
/// <param name="worldResize">The function to return the size</param>
public QuadTreeNode(FRect rect, int maxItems, ResizeDelegate worldResize)
{
ParentNode = null;
Rect = rect;
MaxItems = maxItems;
WorldResize = worldResize;
IsPartitioned = false;
Items = new List <QuadTreePositionItem <T> >();
}
/// <summary>
/// Creates a position item in a QuadTree
/// </summary>
/// <param name="parent">The parent of this item</param>
/// <param name="position">The position of this item</param>
/// <param name="size">The size of this item</param>
public QuadTreePositionItem(T parent, Vector2 position, Vector2 size)
{
this.rect = new FRect(0f, 0f, 1f, 1f);
this.parent = parent;
this.position = position;
this.size = size;
OnMove();
}
/// <summary>
/// Resizes the Quadtree field
/// </summary>
/// <param name="newWorld">The new field</param>
/// <remarks>This is an expensive operation, so try to initialize the world to a big enough size</remarks>
public void Resize(FRect newWorld)
{
// Get all of the items in the tree
List <QuadTreePositionItem <T> > Components = new List <QuadTreePositionItem <T> >();
GetAllItems(ref Components);
// Destroy the head node
headNode.Destroy();
headNode = null;
// Create a new head
headNode = new QuadTreeNode <T>(newWorld, maxItems, Resize);
// Reinsert the items
foreach (QuadTreePositionItem <T> m in Components)
{
headNode.Insert(m);
}
}
/// <summary>
/// Gets a list of items intersecting a specified rectangle
/// </summary>
/// <param name="Rect">The rectangle</param>
/// <param name="ItemsFound">The list to add found items to (list will not be cleared first)</param>
/// <remarks>ItemsFound is assumed to be initialized, and will not be cleared</remarks>
public void GetItems(FRect Rect, ref List <QuadTreePositionItem <T> > ItemsFound)
{
// test the point against this node
if (Rect.Intersects(Rect))
{
// test the point in each item
foreach (QuadTreePositionItem <T> Item in Items)
{
if (Item.Rect.Intersects(Rect))
{
ItemsFound.Add(Item);
}
}
// query all subtrees
if (IsPartitioned)
{
TopLeftNode.GetItems(Rect, ref ItemsFound);
TopRightNode.GetItems(Rect, ref ItemsFound);
BottomLeftNode.GetItems(Rect, ref ItemsFound);
BottomRightNode.GetItems(Rect, ref ItemsFound);
}
}
}
/// <summary>
/// Checks if this rectangle intersects another rectangle
/// </summary>
/// <param name="Rect">The rectangle to check</param>
/// <returns>Whether or not this rectangle intersects the other</returns>
public bool Intersects(FRect Rect)
{
return (!( Bottom < Rect.Top ||
Top > Rect.Bottom ||
Right < Rect.Left ||
Left > Rect.Right ));
}
/// <summary>
/// QuadTree constructor
/// </summary>
/// <param name="worldRect">The world rectangle for this QuadTree (a rectangle containing all items at all times)</param>
/// <param name="maxItems">Maximum number of items in any cell of the QuadTree before partitioning</param>
public QuadTree(FRect worldRect, int maxItems)
{
this.headNode = new QuadTreeNode <T>(worldRect, maxItems, Resize);
this.maxItems = maxItems;
}
