feat(aofix): Better stair ambient occlusion

Author: FalsePattern

src/main/java/com/falsepattern/falsetweaks/config/AOFixConfig.java

@@ -49,6 +49,14 @@ public class AOFixConfig {
     @Config.RequiresMcRestart
     public static boolean patchLittleTiles;
 
+    @Config.Comment({
+            "Stairs and slabs need additional AO workarounds to look good.",
+            "You can toggle these fixes here (requires f3+a world renderer refresh to see the changes)"
+    })
+    @Config.LangKey
+    @Config.DefaultBoolean(true)
+    public static boolean stairAOFix;
+
     static {
         ConfigurationManager.selfInit();
     }

src/main/java/com/falsepattern/falsetweaks/mixin/mixins/client/ao/ChunkCacheMixin.java

@@ -0,0 +1,50 @@
+/*
+ * This file is part of FalseTweaks.
+ *
+ * Copyright (C) 2022-2025 FalsePattern
+ * All Rights Reserved
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * FalseTweaks is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, only version 3 of the License.
+ *
+ * FalseTweaks is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with FalseTweaks. If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package com.falsepattern.falsetweaks.mixin.mixins.client.ao;
+
+import com.falsepattern.falsetweaks.modules.ao.AOChunkCache;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Unique;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Redirect;
+
+import net.minecraft.block.Block;
+import net.minecraft.world.ChunkCache;
+
+@Mixin(ChunkCache.class)
+public abstract class ChunkCacheMixin implements AOChunkCache {
+    @Unique
+    private boolean ft$useNeighborBrightness = true;
+    @Override
+    public void ft$setUseNeighborBrightness(boolean value) {
+        ft$useNeighborBrightness = value;
+    }
+
+    @Redirect(method = "getSkyBlockTypeBrightness",
+              at = @At(value = "INVOKE",
+                       target = "Lnet/minecraft/block/Block;getUseNeighborBrightness()Z"),
+              require = 1)
+    private boolean bypassUseNeighborBrightness(Block instance) {
+        return ft$useNeighborBrightness && instance.getUseNeighborBrightness();
+    }
+}

src/main/java/com/falsepattern/falsetweaks/mixin/plugin/standard/Mixin.java

@@ -141,7 +141,8 @@ public enum Mixin implements IMixins {
 
     AOFix_Universal(Phase.EARLY,
                     () -> ModuleConfig.aoFix && AOFixConfig.universalPatch,
-                    client("ao.RenderBlocksUniversalMixin")),
+                    client("ao.RenderBlocksUniversalMixin",
+                           "ao.ChunkCacheMixin")),
     AOFix_Compat(Phase.EARLY,
                  () -> ModuleConfig.aoFix && AOFixConfig.renderHookCompatMode,
                  client("ao.RenderBlocksCompatMixin")),

src/main/java/com/falsepattern/falsetweaks/modules/ao/AOChunkCache.java

@@ -0,0 +1,27 @@
+/*
+ * This file is part of FalseTweaks.
+ *
+ * Copyright (C) 2022-2025 FalsePattern
+ * All Rights Reserved
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * FalseTweaks is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, only version 3 of the License.
+ *
+ * FalseTweaks is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with FalseTweaks. If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package com.falsepattern.falsetweaks.modules.ao;
+
+public interface AOChunkCache {
+    void ft$setUseNeighborBrightness(boolean value);
+}