public Texture2D SetupTextureAtlas(GraphicsDevice graphicsDevice)
{
var triangles = Models.SelectMany(m => m.ModelTriangles).ToList();
var dict = new Dictionary <KeyValuePair <string, Rectangle>, TrianglesWithCroppedTexture>();
foreach (var triangle in triangles)
{
if (!dict.ContainsKey(triangle.TextureKey))
{
if (!TextureHandler.HasCroppedTexture(triangle.TextureKey))
{
TextureHandler.AddCroppedTexture(triangle.TextureKey, TextureHandler.CropTexture(triangle.OriginalTexture, triangle.OriginalTextureRectangle));
}
dict.Add(triangle.TextureKey, new TrianglesWithCroppedTexture()
{
CroppedTexture = TextureHandler.GetCroppedTexture(triangle.TextureKey).Key,
HasTransparentPixels = TextureHandler.GetCroppedTexture(triangle.TextureKey).Value
});
}
dict[triangle.TextureKey].ModelTriangles.Add(triangle);
}
var packer = new RectanglePacker(4096, 4096);
foreach (var pair in dict)
{
var rect = pair.Value.CroppedTexture.Bounds;
if (!packer.Pack(rect.Width, rect.Height, out rect.X, out rect.Y))
{
throw new Exception("Uh oh, we couldn't pack the rectangles");
}
pair.Value.AtlasRectangle = rect;
}
foreach (var pair in dict)
{
foreach (var triangle in pair.Value.ModelTriangles)
{
triangle.AtlasTextureRectangle = pair.Value.AtlasRectangle;
triangle.HasTransparentPixels = pair.Value.HasTransparentPixels;
}
}
var atlas = new Texture2D(graphicsDevice, 4096, 4096);
foreach (var pair in dict)
{
var data = new Color[pair.Value.CroppedTexture.Width * pair.Value.CroppedTexture.Height];
pair.Value.CroppedTexture.GetData(0, pair.Value.CroppedTexture.Bounds, data, 0, data.Length);
atlas.SetData(0, pair.Value.AtlasRectangle, data, 0, data.Length);
pair.Value.CroppedTexture = null;
}
return(atlas);
}