Emissive textures support

src/main/java/ru/bclib/mixin/client/TextureAtlasMixin.java

@@ -0,0 +1,78 @@
+package ru.bclib.mixin.client;
+
+import com.mojang.blaze3d.platform.NativeImage;
+import net.fabricmc.fabric.impl.client.texture.FabricSprite;
+import net.minecraft.client.renderer.texture.TextureAtlas;
+import net.minecraft.client.renderer.texture.TextureAtlasSprite;
+import net.minecraft.resources.ResourceLocation;
+import net.minecraft.server.packs.resources.Resource;
+import net.minecraft.server.packs.resources.ResourceManager;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Inject;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfoReturnable;
+import ru.bclib.BCLib;
+
+import java.io.IOException;
+
+@Mixin(TextureAtlas.class)
+public class TextureAtlasMixin {
+	private boolean bclib_modifyAtlas;
+	
+	@Inject(method = "<init>*", at = @At("TAIL"))
+	private void bclib_onAtlasInit(ResourceLocation resourceLocation, CallbackInfo info) {
+		bclib_modifyAtlas = resourceLocation.toString().equals("minecraft:textures/atlas/blocks.png");
+	}
+	
+	@Inject(
+		method = "load(Lnet/minecraft/server/packs/resources/ResourceManager;Lnet/minecraft/client/renderer/texture/TextureAtlasSprite$Info;IIIII)Lnet/minecraft/client/renderer/texture/TextureAtlasSprite;",
+		at = @At("HEAD"),
+		cancellable = true
+	)
+	private void bclib_loadSprite(ResourceManager resourceManager, TextureAtlasSprite.Info spriteInfo, int atlasWidth, int atlasHeight, int maxLevel, int posX, int posY, CallbackInfoReturnable<TextureAtlasSprite> info) {
+		ResourceLocation location = spriteInfo.name();
+		if (bclib_modifyAtlas && location.getPath().startsWith("block")) {
+			ResourceLocation emissiveLocation = new ResourceLocation(location.getNamespace(), "textures/" + location.getPath() + "_e.png");
+			if (resourceManager.hasResource(emissiveLocation)) {
+				NativeImage sprite = null;
+				NativeImage emission = null;
+				try {
+					ResourceLocation spriteLocation = new ResourceLocation(location.getNamespace(), "textures/" + location.getPath() + ".png");
+					Resource resource = resourceManager.getResource(spriteLocation);
+					sprite = NativeImage.read(resource.getInputStream());
+					resource.close();
+					
+					resource = resourceManager.getResource(emissiveLocation);
+					emission = NativeImage.read(resource.getInputStream());
+					resource.close();
+				}
+				catch (IOException e) {
+					BCLib.LOGGER.warning(e.getMessage());
+				}
+				if (sprite != null && emission != null) {
+					int width = Math.min(sprite.getWidth(), emission.getWidth());
+					int height = Math.min(sprite.getHeight(), emission.getHeight());
+					for (int x = 0; x < width; x++) {
+						for (int y = 0; y < height; y++) {
+							int argb = emission.getPixelRGBA(x, y);
+							int alpha = (argb >> 24) & 255;
+							if (alpha > 127) {
+								int r = (argb >> 16) & 255;
+								int g = (argb >> 8) & 255;
+								int b = argb & 255;
+								if (r > 0 || g > 0 || b > 0) {
+									argb = (argb & 0x00FFFFFF) | (200 << 24);
+									sprite.setPixelRGBA(x, y, argb);
+								}
+							}
+						}
+					}
+					TextureAtlas self = (TextureAtlas) (Object) this;
+					FabricSprite result = new FabricSprite(self, spriteInfo, maxLevel, atlasWidth, atlasHeight, posX, posY, sprite);
+					info.setReturnValue(result);
+				}
+			}
+		}
+	}
+}

src/main/resources/bclib.mixins.client.json

@@ -6,6 +6,7 @@
 	"client": [
 		"EnchantingTableBlockMixin",
 		"BackgroundRendererMixin",
+		"TextureAtlasMixin",
 	  	"ModelBakeryMixin",
 		"MinecraftMixin"
 	],