Resolve redirect conflict and add more optifine hacks

- Fix entitiesForRendering redirect to be compatible with carpet.
 - Use more reflection for dealing with optifine
 - Fixes issue where flywheel would still be on immediately after enabling optifine shaders

src/main/java/com/jozufozu/flywheel/backend/Backend.java

@@ -41,8 +41,6 @@ public class Backend {
 	}
 
 	public static void refresh() {
-		OptifineHandler.refresh();
-
 		engine = chooseEngine();
 	}
 

src/main/java/com/jozufozu/flywheel/backend/OptifineHandler.java

@@ -1,25 +1,43 @@
 package com.jozufozu.flywheel.backend;
 
-import java.io.BufferedReader;
-import java.io.File;
-import java.io.FileReader;
-import java.io.IOException;
 import java.lang.reflect.Field;
+import java.lang.reflect.Method;
 import java.util.function.BooleanSupplier;
 
-import net.minecraft.client.Minecraft;
+import javax.annotation.Nullable;
+
+import net.minecraft.client.Camera;
+import net.minecraft.client.renderer.culling.Frustum;
 
 public final class OptifineHandler {
 	public static final String OPTIFINE_ROOT_PACKAGE = "net.optifine";
 	public static final String SHADER_PACKAGE = "net.optifine.shaders";
 
 	private static boolean isOptifineInstalled;
-	private static boolean isUsingShaders;
+	private static BooleanSupplier shadersEnabledSupplier;
 	private static BooleanSupplier shadowPassSupplier;
+	private static FrustumConstructor shadowFrustumConstructor;
 
 	private OptifineHandler() {
 	}
 
+	private static FrustumConstructor createShadowFrustumConstructor() {
+		try {
+			Class<?> ofShaders = Class.forName("net.optifine.shaders.ShadersRender");
+			Method method = ofShaders.getDeclaredMethod("makeShadowFrustum", Camera.class, Float.TYPE);
+			method.setAccessible(true);
+			return (cam, pt) -> {
+				try {
+					return (Frustum) method.invoke(null, cam, pt);
+				} catch (Exception ignored) {
+					return null;
+				}
+			};
+		} catch (Exception ignored) {
+			return ($, $$) -> null;
+		}
+	}
+
 	private static BooleanSupplier createShadowPassSupplier() {
 		try {
 			Class<?> ofShaders = Class.forName("net.optifine.shaders.Shaders");
@@ -37,28 +55,21 @@ public final class OptifineHandler {
 		}
 	}
 
-	private static boolean areShadersDisabledInOptifineConfigFile() {
-		File dir = Minecraft.getInstance().gameDirectory;
-
-		File shaderOptions = new File(dir, "optionsshaders.txt");
-
-		boolean shadersOff = true;
-		try (BufferedReader reader = new BufferedReader(new FileReader(shaderOptions))) {
-
-			shadersOff = reader.lines()
-					.anyMatch(it -> {
-						String line = it.replaceAll("\\s", "");
-						if (line.startsWith("shaderPack=")) {
-							String setting = line.substring("shaderPack=".length());
-
-							return setting.equals("OFF") || setting.equals("(internal)");
-						}
-						return false;
-					});
-		} catch (IOException e) {
-			Backend.LOGGER.info("No shader config found.");
+	private static BooleanSupplier createShadersEnabledSupplier() {
+		try {
+			Class<?> ofShaders = Class.forName("net.optifine.shaders.Shaders");
+			Field field = ofShaders.getDeclaredField("shaderPackLoaded");
+			field.setAccessible(true);
+			return () -> {
+				try {
+					return field.getBoolean(null);
+				} catch (IllegalAccessException ignored) {
+					return false;
+				}
+			};
+		} catch (Exception ignored) {
+			return () -> false;
 		}
-		return shadersOff;
 	}
 
 	public static void init() {
@@ -67,21 +78,13 @@ public final class OptifineHandler {
 
 		if (isOptifineInstalled) {
 			Backend.LOGGER.info("Optifine detected.");
-
-			refresh();
 		} else {
 			Backend.LOGGER.info("Optifine not detected.");
 		}
 
+		shadersEnabledSupplier = createShadersEnabledSupplier();
 		shadowPassSupplier = createShadowPassSupplier();
-	}
-
-	public static void refresh() {
-		if (!isOptifineInstalled) return;
-
-		boolean shadersOff = areShadersDisabledInOptifineConfigFile();
-
-		isUsingShaders = !shadersOff;
+		shadowFrustumConstructor = createShadowFrustumConstructor();
 	}
 
 	public static boolean isOptifineInstalled() {
@@ -89,10 +92,26 @@ public final class OptifineHandler {
 	}
 
 	public static boolean isUsingShaders() {
-		return isUsingShaders;
+		return shadersEnabledSupplier.getAsBoolean();
 	}
 
 	public static boolean isShadowPass() {
 		return shadowPassSupplier.getAsBoolean();
 	}
+
+	@Nullable
+	public static Frustum createShadowFrustum(Camera camera, float partialTicks) {
+		var frustum = shadowFrustumConstructor.create(camera, partialTicks);
+		if (frustum != null) {
+			var position = camera.getPosition();
+			frustum.prepare(position.x, position.y, position.z);
+		}
+		return frustum;
+	}
+
+	@FunctionalInterface
+	public interface FrustumConstructor {
+		@Nullable
+		Frustum create(Camera camera, float partialTicks);
+	}
 }

src/main/java/com/jozufozu/flywheel/backend/instancing/InstanceWorld.java

@@ -12,6 +12,7 @@ import com.jozufozu.flywheel.core.Contexts;
 import com.jozufozu.flywheel.core.shader.WorldProgram;
 import com.jozufozu.flywheel.event.BeginFrameEvent;
 import com.jozufozu.flywheel.event.RenderLayerEvent;
+import com.jozufozu.flywheel.util.ClientLevelExtension;
 
 import net.minecraft.client.Minecraft;
 import net.minecraft.client.multiplayer.ClientLevel;
@@ -130,7 +131,8 @@ public class InstanceWorld {
 	public void loadEntities(ClientLevel world) {
 		// Block entities are loaded while chunks are baked.
 		// Entities are loaded with the world, so when chunks are reloaded they need to be re-added.
-		world.entitiesForRendering()
+		ClientLevelExtension.cast(world)
+				.flywheel$getAllLoadedEntities()
 				.forEach(entityInstanceManager::add);
 	}
 

src/main/java/com/jozufozu/flywheel/mixin/CancelEntityRenderMixin.java

@@ -1,51 +0,0 @@
-package com.jozufozu.flywheel.mixin;
-
-import java.util.ArrayList;
-
-import org.spongepowered.asm.mixin.Mixin;
-import org.spongepowered.asm.mixin.injection.At;
-import org.spongepowered.asm.mixin.injection.Group;
-import org.spongepowered.asm.mixin.injection.Redirect;
-
-import com.google.common.collect.Lists;
-import com.jozufozu.flywheel.backend.Backend;
-import com.jozufozu.flywheel.backend.instancing.InstancedRenderRegistry;
-
-import net.minecraft.client.multiplayer.ClientLevel;
-import net.minecraft.client.renderer.LevelRenderer;
-import net.minecraft.world.entity.Entity;
-
-@Mixin(LevelRenderer.class)
-public class CancelEntityRenderMixin {
-
-	// TODO: Don't use redirect
-	@Group(name = "entityFilter", min = 1, max = 1)
-	@Redirect(method = "renderLevel", at = @At(value = "INVOKE", target = "Lnet/minecraft/client/multiplayer/ClientLevel;entitiesForRendering()Ljava/lang/Iterable;"))
-	private Iterable<Entity> filterEntities(ClientLevel world) {
-		Iterable<Entity> entities = world.entitiesForRendering();
-		if (Backend.isOn()) {
-			ArrayList<Entity> filtered = Lists.newArrayList(entities);
-
-			filtered.removeIf(InstancedRenderRegistry::shouldSkipRender);
-
-			return filtered;
-		}
-		return entities;
-	}
-
-//	@Group(name = "entityFilter")
-//	@Redirect(method = "renderLevel", at = @At(value = "INVOKE", target = "Lnet/minecraft/util/ClassInstanceMultiMap;iterator()Ljava/util/Iterator;"))
-//	private Iterator<Entity> filterEntitiesOF(ClassInstanceMultiMap<Entity> classInheritanceMultiMap) {
-//		if (Backend.getInstance()
-//				.canUseInstancing()) {
-//
-//			ArrayList<Entity> filtered = Lists.newArrayList(classInheritanceMultiMap);
-//
-//			InstancedRenderRegistry r = InstancedRenderRegistry.getInstance();
-//			filtered.removeIf(r::shouldSkipRender);
-//
-//			return filtered.iterator();
-//		}
-//		return classInheritanceMultiMap.iterator();
-//	}
-}

src/main/java/com/jozufozu/flywheel/mixin/ClientLevelMixin.java

@@ -0,0 +1,42 @@
+package com.jozufozu.flywheel.mixin;
+
+import java.util.ArrayList;
+
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Shadow;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Inject;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfoReturnable;
+
+import com.google.common.collect.Lists;
+import com.jozufozu.flywheel.backend.Backend;
+import com.jozufozu.flywheel.backend.instancing.InstancedRenderRegistry;
+import com.jozufozu.flywheel.util.ClientLevelExtension;
+
+import net.minecraft.client.multiplayer.ClientLevel;
+import net.minecraft.world.entity.Entity;
+import net.minecraft.world.level.entity.LevelEntityGetter;
+
+@Mixin(ClientLevel.class)
+public abstract class ClientLevelMixin implements ClientLevelExtension {
+
+	@Shadow
+	protected abstract LevelEntityGetter<Entity> getEntities();
+
+	@Override
+	public Iterable<Entity> flywheel$getAllLoadedEntities() {
+		return getEntities().getAll();
+	}
+
+	@Inject(method = "entitiesForRendering", at = @At("RETURN"), cancellable = true)
+	private void filterEntities(CallbackInfoReturnable<Iterable<Entity>> cir) {
+		if (Backend.isOn()) {
+			Iterable<Entity> entities = cir.getReturnValue();
+			ArrayList<Entity> filtered = Lists.newArrayList(entities);
+
+			filtered.removeIf(InstancedRenderRegistry::shouldSkipRender);
+
+			cir.setReturnValue(filtered);
+		}
+	}
+}

src/main/java/com/jozufozu/flywheel/mixin/ShaderCloseMixin.java

@@ -1,35 +0,0 @@
-package com.jozufozu.flywheel.mixin;
-
-import javax.annotation.Nullable;
-
-import org.spongepowered.asm.mixin.Mixin;
-import org.spongepowered.asm.mixin.Shadow;
-import org.spongepowered.asm.mixin.injection.At;
-import org.spongepowered.asm.mixin.injection.Inject;
-import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
-
-import com.jozufozu.flywheel.backend.OptifineHandler;
-
-import net.minecraft.client.Minecraft;
-import net.minecraft.client.gui.screens.Screen;
-import net.minecraft.client.gui.screens.VideoSettingsScreen;
-
-@Mixin(Minecraft.class)
-public class ShaderCloseMixin {
-
-	@Shadow
-	@Nullable
-	public Screen screen;
-
-	@Inject(at = @At("HEAD"), method = "setScreen")
-	private void whenScreenChanges(Screen screen, CallbackInfo info) {
-		if (OptifineHandler.isOptifineInstalled() && screen instanceof VideoSettingsScreen) {
-			Screen old = this.screen;
-			if (old != null && old.getClass()
-					.getName()
-					.startsWith(OptifineHandler.SHADER_PACKAGE)) {
-				OptifineHandler.refresh();
-			}
-		}
-	}
-}

src/main/java/com/jozufozu/flywheel/util/ClientLevelExtension.java

@@ -0,0 +1,22 @@
+package com.jozufozu.flywheel.util;
+
+import net.minecraft.client.multiplayer.ClientLevel;
+import net.minecraft.world.entity.Entity;
+
+public interface ClientLevelExtension {
+
+	/**
+	 * Get an iterator over all entities in this level.
+	 *
+	 * <p>
+	 *     Normally, this would be accomplished by {@link ClientLevel#entitiesForRendering()}, but the output of that
+	 *     method is filtered of entities that are rendered by flywheel. This interface provides a workaround.
+	 * </p>
+	 * @return An iterator over all entities in the level, including entities that are rendered by flywheel.
+	 */
+	Iterable<Entity> flywheel$getAllLoadedEntities();
+
+	static ClientLevelExtension cast(ClientLevel level) {
+		return (ClientLevelExtension) level;
+	}
+}

src/main/resources/flywheel.mixins.json

@@ -10,7 +10,7 @@
     "BufferBuilderMixin",
     "BufferUploaderMixin",
     "CameraMixin",
-    "CancelEntityRenderMixin",
+    "ClientLevelMixin",
     "ChunkRebuildHooksMixin",
     "EntityTypeMixin",
     "FixFabulousDepthMixin",
@@ -23,7 +23,6 @@
     "PausedPartialTickAccessor",
     "RenderTexturesMixin",
     "RenderTypeMixin",
-    "ShaderCloseMixin",
     "atlas.AtlasDataMixin",
     "atlas.SheetDataAccessor",
     "light.LightUpdateMixin",