/// <summary>
/// Comparison function for sorting sprites in an <see cref="ITextureAtlasable"/> by size.
/// </summary>
/// <returns>A signed number indicating the relative values of this instance and value.
/// Less than zero means this instance is less than value. Zero means this instance is equal to value.
/// Greater than zero mean this instance is greater than value.</returns>
/// <exception cref="ArgumentNullException"><paramref name="a" /> is <c>null</c>.</exception>
/// <exception cref="ArgumentNullException"><paramref name="b" /> is <c>null</c>.</exception>
static int SizeCompare(ITextureAtlasable a, ITextureAtlasable b)
{
if (a == null)
{
if (log.IsFatalEnabled)
{
log.Fatal("argument a is null.");
}
throw new ArgumentNullException("a");
}
if (b == null)
{
if (log.IsFatalEnabled)
{
log.Fatal("argument b is null.");
}
throw new ArgumentNullException("b");
}
var aSize = a.SourceRect.Height * a.SourceRect.Width;
var bSize = b.SourceRect.Height * b.SourceRect.Width;
return(bSize.CompareTo(aSize));
}
/// <summary>
/// Inserts a <see cref="ITextureAtlasable"/> into the tree from this <see cref="AtlasTreeNode"/>.
/// </summary>
/// <param name="w">Width of the area to insert into.</param>
/// <param name="h">Height of the area to insert into.</param>
/// <param name="atlasItem">The <see cref="ITextureAtlasable"/> that inserted node is for.</param>
/// <returns>The <see cref="AtlasTreeNode"/> containing the area the claimed, or null if no area of the
/// required size could be found.</returns>
public AtlasTreeNode Insert(int w, int h, ITextureAtlasable atlasItem)
{
if (!IsLeaf)
{
// Insert into children (left first then right)
AtlasTreeNode ret = null;
if (Left != null)
{
ret = Left.Insert(w, h, atlasItem);
}
if (ret == null && Right != null)
{
ret = Right.Insert(w, h, atlasItem);
}
if (ret != null)
{
ret.AtlasNode.ITextureAtlasable = atlasItem;
}
return(ret);
}
else
{
// Check if it fits and not in use
if (ITextureAtlasable != null || w > Rect.Width || h > Rect.Height)
{
return(null);
}
// Perfect fit
if (w == Rect.Width && h == Rect.Height)
{
return(this);
}
// Not a perfect fit, split the node up into new nodes
var diffW = Rect.Width - w;
var diffH = Rect.Height - h;
// Decide which way to split
if (diffW > diffH)
{
// Split vertically
Left = new AtlasTreeNode(new Rectangle(Rect.Left, Rect.Top, w, Rect.Height));
Right = new AtlasTreeNode(new Rectangle(Rect.Left + w, Rect.Top, Rect.Width - w, Rect.Height));
}
else
{
// Split horizontally
Left = new AtlasTreeNode(new Rectangle(Rect.Left, Rect.Top, Rect.Width, h));
Right = new AtlasTreeNode(new Rectangle(Rect.Left, Rect.Top + h, Rect.Width, Rect.Height - h));
}
// Insert the rectangle first new child
var node = Left.Insert(w, h, atlasItem);
// If the insert is a perfect fit, drop the node from the tree to prevent checking it again
if (diffW == 0 || diffH == 0)
{
Left = null;
}
// If the node was created, set the atlas item
if (node != null)
{
node.AtlasNode.ITextureAtlasable = atlasItem;
}
return(node);
}
}
/// <summary>
/// Comparison function for sorting sprites in an <see cref="ITextureAtlasable"/> by size.
/// </summary>
/// <returns>A signed number indicating the relative values of this instance and value.
/// Less than zero means this instance is less than value. Zero means this instance is equal to value.
/// Greater than zero mean this instance is greater than value.</returns>
/// <exception cref="ArgumentNullException"><paramref name="a" /> is <c>null</c>.</exception>
/// <exception cref="ArgumentNullException"><paramref name="b" /> is <c>null</c>.</exception>
static int SizeCompare(ITextureAtlasable a, ITextureAtlasable b)
{
if (a == null)
{
if (log.IsFatalEnabled)
log.Fatal("argument a is null.");
throw new ArgumentNullException("a");
}
if (b == null)
{
if (log.IsFatalEnabled)
log.Fatal("argument b is null.");
throw new ArgumentNullException("b");
}
var aSize = a.SourceRect.Height * a.SourceRect.Width;
var bSize = b.SourceRect.Height * b.SourceRect.Width;
return bSize.CompareTo(aSize);
}
/// <summary>
/// Inserts a <see cref="ITextureAtlasable"/> into the tree from this <see cref="AtlasTreeNode"/>.
/// </summary>
/// <param name="w">Width of the area to insert into.</param>
/// <param name="h">Height of the area to insert into.</param>
/// <param name="atlasItem">The <see cref="ITextureAtlasable"/> that inserted node is for.</param>
/// <returns>The <see cref="AtlasTreeNode"/> containing the area the claimed, or null if no area of the
/// required size could be found.</returns>
public AtlasTreeNode Insert(int w, int h, ITextureAtlasable atlasItem)
{
if (!IsLeaf)
{
// Insert into children (left first then right)
AtlasTreeNode ret = null;
if (Left != null)
ret = Left.Insert(w, h, atlasItem);
if (ret == null && Right != null)
ret = Right.Insert(w, h, atlasItem);
if (ret != null)
ret.AtlasNode.ITextureAtlasable = atlasItem;
return ret;
}
else
{
// Check if it fits and not in use
if (ITextureAtlasable != null || w > Rect.Width || h > Rect.Height)
return null;
// Perfect fit
if (w == Rect.Width && h == Rect.Height)
return this;
// Not a perfect fit, split the node up into new nodes
var diffW = Rect.Width - w;
var diffH = Rect.Height - h;
// Decide which way to split
if (diffW > diffH)
{
// Split vertically
Left = new AtlasTreeNode(new Rectangle(Rect.Left, Rect.Top, w, Rect.Height));
Right = new AtlasTreeNode(new Rectangle(Rect.Left + w, Rect.Top, Rect.Width - w, Rect.Height));
}
else
{
// Split horizontally
Left = new AtlasTreeNode(new Rectangle(Rect.Left, Rect.Top, Rect.Width, h));
Right = new AtlasTreeNode(new Rectangle(Rect.Left, Rect.Top + h, Rect.Width, Rect.Height - h));
}
// Insert the rectangle first new child
var node = Left.Insert(w, h, atlasItem);
// If the insert is a perfect fit, drop the node from the tree to prevent checking it again
if (diffW == 0 || diffH == 0)
Left = null;
// If the node was created, set the atlas item
if (node != null)
node.AtlasNode.ITextureAtlasable = atlasItem;
return node;
}
}
