Render Layer API

FabricRenderLayers.java

package net.fabricmc.fabric.api.client.rendering.v1;

import net.fabricmc.fabric.impl.client.rendering.RenderLayerAccessors;
import net.minecraft.client.render.RenderLayer;
import net.minecraft.client.render.VertexFormat;

/**
 * Extend this to get access to protected members of RenderLayer, e.g. MultiPhaseParameters
 */
public abstract class FabricRenderLayers extends RenderLayer {
	protected FabricRenderLayers() {
		super(null, null, null, 0, false, false, null, null);
	}

	/**Makes a render layer**/
	protected static RenderLayer create(String name, VertexFormat vertexFormat,
		VertexFormat.DrawMode drawMode, int expectedBufferSize, RenderLayer.MultiPhaseParameters phaseParameters) {
		return RenderLayerAccessors.create(name, vertexFormat, drawMode, expectedBufferSize, phaseParameters);
	}
}

RenderLayerAccessors.java

package net.fabricmc.fabric.impl.client.rendering;


import net.fabricmc.loader.api.FabricLoader;
import net.fabricmc.loader.api.MappingResolver;
import net.minecraft.client.render.RenderLayer;
import net.minecraft.client.render.VertexFormat;

import java.lang.invoke.MethodHandle;
import java.lang.invoke.MethodHandles;
import java.lang.invoke.MethodType;

public abstract class RenderLayerAccessors extends RenderLayer
{
	private RenderLayerAccessors() {
		super(null, null, null, 0, false, false, null, null);
	}

	// TODO Replace with Global Access Widener for MultiPhaseParameters & Mixin @Invoker for RenderLayer.of()
	private static final MethodHandle RENDER_LAYER__OF;
	static {
		try {
			var lookup = MethodHandles.privateLookupIn(RenderLayer.class, MethodHandles.lookup());
			MappingResolver mappings = FabricLoader.getInstance().getMappingResolver(); 
			{
				var methodName = mappings.mapMethodName("intermediary", "net.minecraft.class_1921", "method_24048",
						"(Ljava/lang/String;Lnet/minecraft/class_293;Lnet/minecraft/class_293$class_5596;"
								+ "ILnet/minecraft/class_1921$class_4688;)Lnet/minecraft/class_1921$class_4687;");
				var renderLayer$Multiphase = Class.forName(mappings.mapClassName("intermediary",
						"net.minecraft.class_1921$class_4687"));
				var methodDesc = MethodType.methodType(renderLayer$Multiphase, String.class, VertexFormat.class,
						VertexFormat.DrawMode.class, int.class, MultiPhaseParameters.class);
				RENDER_LAYER__OF = lookup.findStatic(RenderLayer.class, methodName, methodDesc)
						.asType(methodDesc.changeReturnType(RenderLayer.class));
			}
		}
		catch (IllegalAccessException | ClassNotFoundException | NoSuchMethodException e) {
			throw new RuntimeException("Failed to initialise RenderLayer method handles", e);
		}
	}

	public static RenderLayer create(String name, VertexFormat vertexFormat,
		VertexFormat.DrawMode drawMode, int expectedBufferSize, RenderLayer.MultiPhaseParameters phaseParameters) {
		try {
			return (RenderLayer) RENDER_LAYER__OF.invokeExact(name, vertexFormat,
					drawMode, expectedBufferSize, phaseParameters);
		}
		catch (Throwable e) {
			throw new RuntimeException("Failed to invoke RenderLayer.of method handle", e);
		}
	}
}

TestRenderLayers.java

package net.fabricmc.fabric.test.rendering.client;

import net.fabricmc.fabric.api.client.rendering.v1.FabricRenderLayers;
import net.minecraft.client.render.RenderLayer;
import net.minecraft.client.render.RenderPhase;
import net.minecraft.client.render.VertexFormat.DrawMode;
import net.minecraft.client.render.VertexFormats;

public class TestRenderLayers extends FabricRenderLayers {
	public static final RenderLayer COLOUR_QUADS;
	static {
		MultiPhaseParameters multiPhaseParameters = MultiPhaseParameters.builder()
				.shader(RenderPhase.COLOR_SHADER)
				.cull(RenderPhase.DISABLE_CULLING)
				.transparency(RenderPhase.TRANSLUCENT_TRANSPARENCY)
				.build(false);
		long start = System.currentTimeMillis();
		COLOUR_QUADS = create("render_layer_testmod:colour_quads",
				VertexFormats.POSITION_COLOR, DrawMode.QUADS, 256, multiPhaseParameters);
	}
}