SpriteSheetManager.java

package codechicken.lib.render;

import codechicken.lib.render.TextureUtils.IIconRegister;
import net.minecraft.client.renderer.texture.TextureAtlasSprite;
import net.minecraft.client.renderer.texture.TextureMap;
import net.minecraft.util.ResourceLocation;
import net.minecraftforge.fml.relauncher.Side;
import net.minecraftforge.fml.relauncher.SideOnly;

import java.util.ArrayList;
import java.util.HashMap;

public class SpriteSheetManager {
    @SideOnly(Side.CLIENT)
    public static class SpriteSheet implements IIconRegister {
        private int tilesX;
        private int tilesY;
        private ArrayList<Integer> newSprites = new ArrayList<Integer>();
        private TextureSpecial[] sprites;
        private ResourceLocation resource;
        private TextureDataHolder texture;
        private int spriteWidth;
        private int spriteHeight;

        public int atlasIndex;

        private SpriteSheet(int tilesX, int tilesY, ResourceLocation textureFile) {
            this.tilesX = tilesX;
            this.tilesY = tilesY;
            this.resource = textureFile;
            sprites = new TextureSpecial[tilesX * tilesY];
        }

        public void requestIndicies(int... indicies) {
            for (int i : indicies) {
                setupSprite(i);
            }
        }

        @Override
        public void registerIcons(TextureMap textureMap) {
            if (TextureUtils.refreshTexture(textureMap, resource.getResourcePath())) {
                reloadTexture();
                for (TextureSpecial sprite : sprites) {
                    if (sprite != null) {
                        textureMap.setTextureEntry(sprite.getIconName(), sprite);
                    }
                }
            } else {
                for (int i : newSprites) {
                    textureMap.setTextureEntry(sprites[i].getIconName(), sprites[i]);
                }
            }
            newSprites.clear();
        }

        public TextureSpecial setupSprite(int i) {
            if (sprites[i] == null) {
                String name = resource + "_" + i;
                sprites[i] = new TextureSpecial(name).baseFromSheet(this, i);
                newSprites.add(i);
            }
            return sprites[i];
        }

        private void reloadTexture() {
            texture = TextureUtils.loadTexture(resource);
            spriteWidth = texture.width / tilesX;
            spriteHeight = texture.height / tilesY;
        }

        public TextureAtlasSprite getSprite(int index) {
            TextureAtlasSprite i = sprites[index];
            if (i == null) {
                throw new IllegalArgumentException("Sprite at index: " + index + " from texture file " + resource + " was not preloaded.");
            }
            return i;
        }

        public TextureDataHolder createSprite(int spriteIndex) {
            int sx = spriteIndex % tilesX;
            int sy = spriteIndex / tilesX;
            TextureDataHolder sprite = new TextureDataHolder(spriteWidth, spriteHeight);
            TextureUtils.copySubImg(texture.data, texture.width, sx * spriteWidth, sy * spriteHeight, spriteWidth, spriteHeight, sprite.data, spriteWidth, 0, 0);
            return sprite;
        }

        public int spriteWidth() {
            return spriteWidth;
        }

        public int spriteHeight() {
            return spriteHeight;
        }

        public TextureSpecial bindTextureFX(int i, TextureFX textureFX) {
            return setupSprite(i).addTextureFX(textureFX);
        }

        public SpriteSheet selfRegister(int atlas) {
            TextureUtils.addIconRegister(this);
            return this;
        }
    }

    private static HashMap<String, SpriteSheet> spriteSheets = new HashMap<String, SpriteSheet>();

    public static SpriteSheet getSheet(ResourceLocation resource) {
        return getSheet(16, 16, resource);
    }

    public static SpriteSheet getSheet(int tilesX, int tilesY, ResourceLocation resource) {
        SpriteSheet sheet = spriteSheets.get(resource.toString());
        if (sheet == null) {
            spriteSheets.put(resource.toString(), sheet = new SpriteSheet(tilesX, tilesY, resource));
        }
        return sheet;
    }
}