Tweak light face computation to improve lighting on slopes

common/src/main/java/com/copycatsplus/copycats/foundation/copycat/model/assembly/MutableQuad.java

@@ -31,17 +31,19 @@ public Direction computeLightFace() {
         };
     }
 
-    private static Axis longestAxis(double normalX, double normalY, double normalZ) {
+    private static final double EPSILON = 0.05;
+
+    public static Axis longestAxis(double normalX, double normalY, double normalZ) {
         Axis result = Axis.Y;
         double longest = Math.abs(normalY);
         double a = Math.abs(normalX);
 
-        if (a > longest) {
+        if (a > longest + EPSILON) {
             result = Axis.X;
             longest = a;
         }
 
-        return Math.abs(normalZ) > longest
+        return Math.abs(normalZ) > longest + EPSILON
                 ? Axis.Z : result;
     }
 

fabric/src/main/java/com/copycatsplus/copycats/fabric/mixin/compat/indium/GeometryHelperMixin.java

@@ -0,0 +1,23 @@
+package com.copycatsplus.copycats.fabric.mixin.compat.indium;
+
+import com.copycatsplus.copycats.foundation.copycat.model.assembly.MutableQuad;
+import link.infra.indium.renderer.helper.GeometryHelper;
+import net.minecraft.core.Direction;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Pseudo;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Inject;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfoReturnable;
+
+@Mixin(GeometryHelper.class)
+@Pseudo
+public class GeometryHelperMixin {
+    @Inject(
+            method = "longestAxis(FFF)Lnet/minecraft/core/Direction$Axis;",
+            at = @At("HEAD"),
+            cancellable = true
+    )
+    private static void longestAxis(float normalX, float normalY, float normalZ, CallbackInfoReturnable<Direction.Axis> cir) {
+        cir.setReturnValue(MutableQuad.longestAxis(normalX, normalY, normalZ));
+    }
+}

fabric/src/main/java/com/copycatsplus/copycats/fabric/mixin/copycat/base/GeometryHelperMixin.java

@@ -0,0 +1,23 @@
+package com.copycatsplus.copycats.fabric.mixin.copycat.base;
+
+import com.copycatsplus.copycats.foundation.copycat.model.assembly.MutableQuad;
+import net.fabricmc.fabric.impl.client.indigo.renderer.helper.GeometryHelper;
+import net.minecraft.core.Direction;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Pseudo;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Inject;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfoReturnable;
+
+@Mixin(GeometryHelper.class)
+@Pseudo
+public class GeometryHelperMixin {
+    @Inject(
+            method = "longestAxis(FFF)Lnet/minecraft/core/Direction$Axis;",
+            at = @At("HEAD"),
+            cancellable = true
+    )
+    private static void longestAxis(float normalX, float normalY, float normalZ, CallbackInfoReturnable<Direction.Axis> cir) {
+        cir.setReturnValue(MutableQuad.longestAxis(normalX, normalY, normalZ));
+    }
+}

fabric/src/main/resources/copycats-fabric.mixins.json

@@ -6,11 +6,13 @@
   "compatibilityLevel": "JAVA_17",
   "mixins": [
     "HolderReferenceMixin",
+    "compat.indium.GeometryHelperMixin",
     "compat.registrate.CreateRegistrateMixin",
     "copycat.base.CopycatBlockEntityMixin$BlockEntityWithoutAttachmentData",
     "copycat.base.CopycatBlockEntityMixin$FluidPipeData",
     "copycat.base.CopycatBlockEntityMixin$StraightPipeData",
     "copycat.base.CopycatBlockMixin",
+    "copycat.base.GeometryHelperMixin",
     "copycat.base.multistate.MultiStateCopycatBlockEntityMixin$BlockEntityWithoutAttachmentData",
     "copycat.base.multistate.MultiStateCopycatBlockMixin"
   ],