Allow fluid variant colors to depend on the position (#1620)

* Allow fluid variant colors to depend on the position

Also add a smarter FluidVariantRendering#getTooltip.

* Add fluid variant rendering testmod

* 255/256 is not 1

* Actually it's in the top left

fabric-transfer-api-v1/build.gradle

@@ -11,6 +11,7 @@ moduleDependencies(project, [
 
 dependencies {
 	testmodImplementation project(path: ':fabric-object-builder-api-v1', configuration: 'dev')
+	testmodImplementation project(path: ':fabric-rendering-v1', configuration: 'dev')
 	testmodImplementation project(path: ':fabric-resource-loader-v0', configuration: 'dev')
 	testmodImplementation project(path: ':fabric-tag-extensions-v0', configuration: 'dev')
 	testmodImplementation project(path: ':fabric-tool-attribute-api-v1', configuration: 'dev')

fabric-transfer-api-v1/src/main/java/net/fabricmc/fabric/api/transfer/v1/client/fluid/FluidVariantRenderHandler.java

@@ -24,6 +24,8 @@ import org.jetbrains.annotations.Nullable;
 import net.minecraft.client.item.TooltipContext;
 import net.minecraft.client.texture.Sprite;
 import net.minecraft.text.Text;
+import net.minecraft.util.math.BlockPos;
+import net.minecraft.world.BlockRenderView;
 
 import net.fabricmc.api.EnvType;
 import net.fabricmc.api.Environment;
@@ -76,14 +78,29 @@ public interface FluidVariantRenderHandler {
 	}
 
 	/**
-	 * Return the color to use when rendering {@linkplain #getSprite the sprite} of this fluid variant.
+	 * @deprecated Use and implement {@linkplain #getColor(FluidVariant, BlockRenderView, BlockPos) the other more general overload}.
+	 * This one will be removed in a future iteration of the API.
 	 */
+	@Deprecated(forRemoval = true)
 	default int getColor(FluidVariant fluidVariant) {
+		return getColor(fluidVariant, null, null);
+	}
+
+	/**
+	 * Return the color to use when rendering {@linkplain #getSprite the sprite} of this fluid variant.
+	 * Transparency (alpha) will generally be taken into account and should be specified as well.
+	 *
+	 * <p>The world and position are optional context parameters and may be {@code null}.
+	 * If they are null, this method must return a location-independent color.
+	 * If they are provided, this method may return a color that depends on the location.
+	 * For example, water returns the biome-dependent color if the context parameters are specified, or its default color if one of them is null.
+	 */
+	default int getColor(FluidVariant fluidVariant, @Nullable BlockRenderView view, @Nullable BlockPos pos) {
 		// Use the fluid render handler by default.
 		FluidRenderHandler fluidRenderHandler = FluidRenderHandlerRegistry.INSTANCE.get(fluidVariant.getFluid());
 
 		if (fluidRenderHandler != null) {
-			return fluidRenderHandler.getFluidColor(null, null, fluidVariant.getFluid().getDefaultState());
+			return fluidRenderHandler.getFluidColor(view, pos, fluidVariant.getFluid().getDefaultState()) | 255 << 24;
 		} else {
 			return -1;
 		}

fabric-transfer-api-v1/src/main/java/net/fabricmc/fabric/api/transfer/v1/client/fluid/FluidVariantRendering.java

@@ -22,13 +22,16 @@ import java.util.List;
 import org.jetbrains.annotations.ApiStatus;
 import org.jetbrains.annotations.Nullable;
 
+import net.minecraft.client.MinecraftClient;
 import net.minecraft.client.item.TooltipContext;
 import net.minecraft.client.texture.Sprite;
 import net.minecraft.fluid.Fluid;
 import net.minecraft.text.LiteralText;
 import net.minecraft.text.Text;
 import net.minecraft.util.Formatting;
+import net.minecraft.util.math.BlockPos;
 import net.minecraft.util.registry.Registry;
+import net.minecraft.world.BlockRenderView;
 
 import net.fabricmc.api.EnvType;
 import net.fabricmc.api.Environment;
@@ -81,7 +84,17 @@ public class FluidVariantRendering {
 	}
 
 	/**
-	 * Return the tooltip for the passed fluid variant, including the name and additional lines if available
+	 * Return a mutable list: the tooltip for the passed fluid variant, including the name and additional lines if available
+	 * and the id of the fluid if advanced tooltips are enabled.
+	 *
+	 * <p>Compared to {@linkplain #getTooltip(FluidVariant, TooltipContext) the other overload}, the current tooltip context is automatically used.
+	 */
+	public static List<Text> getTooltip(FluidVariant fluidVariant) {
+		return getTooltip(fluidVariant, MinecraftClient.getInstance().options.advancedItemTooltips ? TooltipContext.Default.ADVANCED : TooltipContext.Default.NORMAL);
+	}
+
+	/**
+	 * Return a mutable list: the tooltip for the passed fluid variant, including the name and additional lines if available
 	 * and the id of the fluid if advanced tooltips are enabled.
 	 */
 	public static List<Text> getTooltip(FluidVariant fluidVariant, TooltipContext context) {
@@ -113,10 +126,21 @@ public class FluidVariantRendering {
 	}
 
 	/**
-	 * Return the color that should be used to render {@linkplain #getSprite the sprite} of the passed fluid variant.
+	 * Return the position-independent color that should be used to render {@linkplain #getSprite the sprite} of the passed fluid variant.
 	 */
 	public static int getColor(FluidVariant fluidVariant) {
-		return getHandlerOrDefault(fluidVariant.getFluid()).getColor(fluidVariant);
+		return getColor(fluidVariant, null, null);
+	}
+
+	/**
+	 * Return the color that should be used when rendering {@linkplain #getSprite the sprite} of the passed fluid variant.
+	 *
+	 * <p>If the world and the position parameters are null, a position-independent color is returned.
+	 * If the world and position parameters are not null, the color may depend on the position.
+	 * For example, if world and position are passed, water will use them to return a biome-dependent color.
+	 */
+	public static int getColor(FluidVariant fluidVariant, @Nullable BlockRenderView view, @Nullable BlockPos pos) {
+		return getHandlerOrDefault(fluidVariant.getFluid()).getColor(fluidVariant, view, pos);
 	}
 
 	/**

fabric-transfer-api-v1/src/testmod/java/net/fabricmc/fabric/test/transfer/ingame/client/FluidVariantRenderTest.java

@@ -0,0 +1,89 @@
+/*
+ * Copyright (c) 2016, 2017, 2018, 2019 FabricMC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package net.fabricmc.fabric.test.transfer.ingame.client;
+
+import com.mojang.blaze3d.systems.RenderSystem;
+
+import net.minecraft.client.MinecraftClient;
+import net.minecraft.client.render.BufferBuilder;
+import net.minecraft.client.render.BufferRenderer;
+import net.minecraft.client.render.GameRenderer;
+import net.minecraft.client.render.Tessellator;
+import net.minecraft.client.render.VertexFormat;
+import net.minecraft.client.render.VertexFormats;
+import net.minecraft.client.texture.Sprite;
+import net.minecraft.client.texture.SpriteAtlasTexture;
+import net.minecraft.client.util.math.MatrixStack;
+import net.minecraft.entity.player.PlayerEntity;
+import net.minecraft.fluid.Fluids;
+import net.minecraft.util.math.BlockPos;
+import net.minecraft.util.math.Matrix4f;
+import net.minecraft.world.World;
+
+import net.fabricmc.api.ClientModInitializer;
+import net.fabricmc.fabric.api.client.rendering.v1.HudRenderCallback;
+import net.fabricmc.fabric.api.transfer.v1.client.fluid.FluidVariantRendering;
+import net.fabricmc.fabric.api.transfer.v1.fluid.FluidVariant;
+
+/**
+ * Renders the water sprite in the top left of the screen, to make sure that it correctly depends on the position.
+ */
+public class FluidVariantRenderTest implements ClientModInitializer {
+	@Override
+	public void onInitializeClient() {
+		HudRenderCallback.EVENT.register((matrices, tickDelta) -> {
+			PlayerEntity player = MinecraftClient.getInstance().player;
+			if (player == null) return;
+			drawFluidInGui(matrices, FluidVariant.of(Fluids.WATER), player.world, player.getBlockPos(), 0, 0);
+		});
+	}
+
+	private static void drawFluidInGui(MatrixStack ms, FluidVariant fluid, World world, BlockPos pos, int i, int j) {
+		RenderSystem.setShaderTexture(0, SpriteAtlasTexture.BLOCK_ATLAS_TEXTURE);
+		Sprite sprite = FluidVariantRendering.getSprite(fluid);
+		int color = FluidVariantRendering.getColor(fluid, world, pos);
+
+		if (sprite == null) return;
+
+		float r = ((color >> 16) & 255) / 255f;
+		float g = ((color >> 8) & 255) / 255f;
+		float b = (color & 255) / 255f;
+		RenderSystem.disableDepthTest();
+
+		RenderSystem.setShader(GameRenderer::getPositionColorTexShader);
+		BufferBuilder bufferBuilder = Tessellator.getInstance().getBuffer();
+		bufferBuilder.begin(VertexFormat.DrawMode.QUADS, VertexFormats.POSITION_COLOR_TEXTURE);
+		float x0 = (float) i;
+		float y0 = (float) j;
+		float x1 = x0 + 16;
+		float y1 = y0 + 16;
+		float z = 0.5f;
+		float u0 = sprite.getMinU();
+		float v0 = sprite.getMinV();
+		float u1 = sprite.getMaxU();
+		float v1 = sprite.getMaxV();
+		Matrix4f model = ms.peek().getModel();
+		bufferBuilder.vertex(model, x0, y1, z).color(r, g, b, 1).texture(u0, v1).next();
+		bufferBuilder.vertex(model, x1, y1, z).color(r, g, b, 1).texture(u1, v1).next();
+		bufferBuilder.vertex(model, x1, y0, z).color(r, g, b, 1).texture(u1, v0).next();
+		bufferBuilder.vertex(model, x0, y0, z).color(r, g, b, 1).texture(u0, v0).next();
+		bufferBuilder.end();
+		BufferRenderer.draw(bufferBuilder);
+
+		RenderSystem.enableDepthTest();
+	}
+}

fabric-transfer-api-v1/src/testmod/resources/fabric.mod.json

@@ -12,6 +12,9 @@
     "main": [
       "net.fabricmc.fabric.test.transfer.ingame.TransferTestInitializer",
       "net.fabricmc.fabric.test.transfer.unittests.UnitTestsInitializer"
+    ],
+    "client": [
+      "net.fabricmc.fabric.test.transfer.ingame.client.FluidVariantRenderTest"
     ]
   }
 }