public ITextureAtlas CreateUnpacked(uint maxWidth, uint bytesPerPixel)
{
uint width = 0u;
uint height = 0u;
uint xOffset = 0u;
uint yOffset = 0u;
Dictionary <uint, Position> textureOffsets = new Dictionary <uint, Position>();
foreach (var textureEntry in textures)
{
var textureIndex = textureEntry.Key;
var texture = textureEntry.Value;
if (xOffset + texture.Width <= maxWidth)
{
if (yOffset + texture.Height > height)
{
height = yOffset + (uint)texture.Height;
}
textureOffsets.Add(textureIndex, new Position((int)xOffset, (int)yOffset));
xOffset += (uint)texture.Width;
if (xOffset > width)
{
width = xOffset;
}
}
else
{
xOffset = 0;
yOffset = height;
height = yOffset + (uint)texture.Height;
textureOffsets.Add(textureIndex, new Position((int)xOffset, (int)yOffset));
xOffset += (uint)texture.Width;
if (xOffset > width)
{
width = xOffset;
}
}
}
// create texture
var atlasTexture = new MutableTexture(state, (int)width, (int)height, bytesPerPixel);
foreach (var offset in textureOffsets)
{
var subTexture = textures[offset.Key];
atlasTexture.AddSubTexture(offset.Value, subTexture.Data, subTexture.Width, subTexture.Height);
}
atlasTexture.Finish(0);
return(new TextureAtlas(atlasTexture, textureOffsets));
}
// Note: It is not the best texture packing algorithm but it will do its job
public ITextureAtlas Create(uint bytesPerPixel)
{
// sort textures by similar heights (16-pixel bands)
// heights of items are < key * 16
// value = list of texture indices
Dictionary <uint, List <uint> > textureCategories = new Dictionary <uint, List <uint> >();
Dictionary <uint, uint> textureCategoryMinValues = new Dictionary <uint, uint>();
Dictionary <uint, uint> textureCategoryMaxValues = new Dictionary <uint, uint>();
Dictionary <uint, uint> textureCategoryTotalWidth = new Dictionary <uint, uint>();
foreach (var texture in textures)
{
uint category = (uint)texture.Value.Height / 16u;
if (!textureCategories.ContainsKey(category))
{
textureCategories.Add(category, new List <uint>());
textureCategoryMinValues.Add(category, (uint)texture.Value.Height);
textureCategoryMaxValues.Add(category, (uint)texture.Value.Height);
textureCategoryTotalWidth.Add(category, (uint)texture.Value.Width);
}
else
{
if (texture.Value.Height < textureCategoryMinValues[category])
{
textureCategoryMinValues[category] = (uint)texture.Value.Height;
}
if (texture.Value.Height > textureCategoryMaxValues[category])
{
textureCategoryMaxValues[category] = (uint)texture.Value.Height;
}
textureCategoryTotalWidth[category] += (uint)texture.Value.Width;
}
textureCategories[category].Add(texture.Key);
}
var filteredTextureCategories = new List <KeyValuePair <uint, List <uint> > >();
foreach (var category in textureCategories)
{
if (textureCategories[category.Key].Count == 0)
{
continue; // was merged with lower category
}
// merge categories with minimal differences
if (textureCategoryMinValues[category.Key] >= category.Key * 16 + 8 &&
textureCategories.ContainsKey(category.Key + 1) &&
textureCategoryMaxValues[category.Key + 1] <= (category.Key + 1) * 16 + 8)
{
textureCategories[category.Key].AddRange(textureCategories[category.Key + 1]);
textureCategoryMaxValues[category.Key] = Math.Max(textureCategoryMaxValues[category.Key], textureCategoryMaxValues[category.Key + 1]);
textureCategories[category.Key + 1].Clear();
}
filteredTextureCategories.Add(new KeyValuePair <uint, List <uint> >(textureCategoryMaxValues[category.Key], textureCategories[category.Key]));
}
filteredTextureCategories.Sort(new TextureCategorySorter());
// now we have a sorted category list with all texture indices
uint maxWidth = Math.Max(512u, textureCategoryMaxValues.Max(m => m.Value));
uint width = 0u;
uint height = 0u;
uint xOffset = 0u;
uint yOffset = 0u;
Dictionary <uint, Position> textureOffsets = new Dictionary <uint, Position>();
// create texture offsets
foreach (var category in filteredTextureCategories)
{
foreach (var textureIndex in category.Value)
{
var texture = textures[textureIndex];
if (xOffset + texture.Width <= maxWidth)
{
if (yOffset + texture.Height > height)
{
height = yOffset + (uint)texture.Height;
}
textureOffsets.Add(textureIndex, new Position((int)xOffset, (int)yOffset));
xOffset += (uint)texture.Width;
if (xOffset > width)
{
width = xOffset;
}
}
else
{
xOffset = 0;
yOffset = height;
height = yOffset + (uint)texture.Height;
textureOffsets.Add(textureIndex, new Position((int)xOffset, (int)yOffset));
xOffset += (uint)texture.Width;
if (xOffset > width)
{
width = xOffset;
}
}
}
if (xOffset > maxWidth - 320) // we do not expect textures with a width greater than 320
{
xOffset = 0;
yOffset = height;
}
}
// create texture
var atlasTexture = new MutableTexture(state, (int)width, (int)height, bytesPerPixel);
foreach (var offset in textureOffsets)
{
var subTexture = textures[offset.Key];
atlasTexture.AddSubTexture(offset.Value, subTexture.Data, subTexture.Width, subTexture.Height);
}
atlasTexture.Finish(0);
return(new TextureAtlas(atlasTexture, textureOffsets));
}