Opentk/Source/Utilities/TexturePacker.cs
2009-02-13 19:09:38 +00:00

201 lines
6.6 KiB
C#

#region --- License ---
/* Copyright (c) 2006, 2007 Stefanos Apostolopoulos
* See license.txt for license info
*/
#endregion
using System;
using System.Collections.Generic;
using System.Text;
using System.Drawing;
using System.Drawing.Imaging;
namespace OpenTK
{
class TexturePacker<T> where T : IPackable<T>
{
Node root;
#region --- Constructors ---
public TexturePacker(int width, int height)
{
if (width <= 0)
throw new ArgumentOutOfRangeException("width", width, "Must be greater than zero.");
if (height <= 0)
throw new ArgumentOutOfRangeException("height", height, "Must be greater than zero.");
root = new Node();
root.Rect = new Rectangle(0, 0, width, width);
}
#endregion
#region --- Public Methods ---
#region public Rectangle Add(T item)
/// <summary>
/// Packs the given item into the free space of the TexturePacker.
/// </summary>
/// <param name="item">The item to pack.</param>
/// <returns>A System.Drawing.Rectangle containing the coordinates of the packed item.</returns>
/// <exception cref="InvalidOperationException">Occurs if the item is larger than the available TexturePacker area</exception>
/// <exception cref="ArgumentException">Occurs if the item already exists in the TexturePacker.</exception>
public void Add(T item, out Rectangle rect)
{
if (item.Width > root.Rect.Width || item.Height > root.Rect.Height)
throw new InvalidOperationException("The item is too large for this TexturePacker");
Node node;
//if (!items.ContainsKey(item))
{
node = root.Insert(item);
// Tree is full and insertion failed:
if (node == null)
throw new TexturePackerFullException();
//items.Add(item, node);
rect = node.Rect;
}
//throw new ArgumentException("The item already exists in the TexturePacker.", "item");
}
#endregion
#region public void Clear()
/// <summary>
/// Discards all packed items.
/// </summary>
public void Clear()
{
//items.Clear();
root.Clear();
}
#endregion
#region public void ChangeSize(int new_width, int new_height)
/// <summary>
/// Changes the dimensions of the TexturePacker surface.
/// </summary>
/// <param name="new_width">The new width of the TexturePacker surface.</param>
/// <param name="new_height">The new height of the TexturePacker surface.</param>
/// <remarks>Changing the size of the TexturePacker surface will implicitly call TexturePacker.Clear().</remarks>
/// <seealso cref="Clear"/>
public void ChangeSize(int new_width, int new_height)
{
throw new NotImplementedException();
}
#endregion
#endregion
#region Node
class Node
{
public Node()
{
}
Node left, right;
Rectangle rect;
int use_count;
public Rectangle Rect { get { return rect; } set { rect = value; } }
public Node Left { get { return left; } set { left = value; } }
public Node Right { get { return right; } set { right = value; } }
#region --- Constructor ---
public bool Leaf
{
get { return left == null && right == null; }
}
#endregion
#region public Node Insert(T item)
public Node Insert(T item)
{
if (!this.Leaf)
{
// Recurse towards left child, and if that fails, towards the right.
Node new_node = left.Insert(item);
return new_node ?? right.Insert(item);
}
else
{
// We have recursed to a leaf.
// If it is not empty go back.
if (use_count != 0)
return null;
// If this leaf is too small go back.
if (rect.Width < item.Width || rect.Height < item.Height)
return null;
// If this leaf is the right size, insert here.
if (rect.Width == item.Width && rect.Height == item.Height)
{
use_count = 1;
return this;
}
// This leaf is too large, split it up. We'll decide which way to split
// by checking the width and height difference between this rectangle and
// out item's bounding box. If the width difference is larger, we'll split
// horizontaly, else verticaly.
left = new Node();
right = new Node();
int dw = this.rect.Width - item.Width + 1;
int dh = this.rect.Height - item.Height + 1;
if (dw > dh)
{
left.rect = new Rectangle(rect.Left, rect.Top, item.Width, rect.Height);
right.rect = new Rectangle(rect.Left + item.Width, rect.Top, rect.Width - item.Width, rect.Height);
}
else
{
left.rect = new Rectangle(rect.Left, rect.Top, rect.Width, item.Height);
right.rect = new Rectangle(rect.Left, rect.Top + item.Height, rect.Width, rect.Height - item.Height);
}
return left.Insert(item);
}
}
#endregion
#region public void Clear()
public void Clear()
{
if (left != null)
left.Clear();
if (right != null)
right.Clear();
left = right = null;
}
#endregion
}
#endregion
}
class TexturePackerFullException : Exception
{
public TexturePackerFullException() : base("There is not enough space to add this item. Consider calling the Clear() method.") { }
}
}