fix: VertexAPI broken without BSP sorting enabled

Author: FalsePattern

src/main/java/com/falsepattern/falsetweaks/mixin/mixins/client/vertexapi/QuadComparatorMixin.java

@@ -0,0 +1,89 @@
+/*
+ * 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.vertexapi;
+
+import com.falsepattern.falsetweaks.Compat;
+import com.falsepattern.falsetweaks.modules.vertexapi.VertexInfo;
+import lombok.val;
+import org.joml.Math;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Overwrite;
+import org.spongepowered.asm.mixin.Shadow;
+import org.spongepowered.asm.mixin.Unique;
+
+import net.minecraft.client.util.QuadComparator;
+
+import java.util.Comparator;
+
+@Mixin(value = QuadComparator.class,
+       //Swansong is 900
+       //Overwritten by other stuff at level 1000
+       priority = 950)
+public abstract class QuadComparatorMixin implements Comparator<Integer> {
+    @Shadow public int[] field_147627_d;
+
+    @Shadow public float field_147630_a;
+
+    @Shadow public float field_147628_b;
+
+    @Shadow public float field_147629_c;
+
+    /**
+     * @author FalsePattern
+     * @reason VertexAPI compat
+     */
+    @Overwrite
+    public int compare(Integer o1, Integer o2) {
+        val vertexData = this.field_147627_d;
+        val stride = VertexInfo.getVertexInfo(Compat.shaderType(), 1);
+        val stride2 = stride * 2;
+        val stride3 = stride * 3;
+        val refX = field_147630_a;
+        val refY = field_147628_b;
+        val refZ = field_147629_c;
+        val aSQ = ft$getDistSQ(vertexData, o1, stride, stride2, stride3, refX, refY, refZ);
+        val bSQ = ft$getDistSQ(vertexData, o2, stride, stride2, stride3, refX, refY, refZ);
+        return Float.compare(bSQ, aSQ);
+    }
+
+    @Unique
+    private static float ft$getDistSQ(int[] vertexData, int primitive, int stride, int stride2, int stride3, float refX, float refY, float refZ) {
+        val x1 = Float.intBitsToFloat(vertexData[primitive]) - refX;
+        val y1 = Float.intBitsToFloat(vertexData[primitive + 1]) - refY;
+        val z1 = Float.intBitsToFloat(vertexData[primitive + 2]) - refZ;
+        val x2 = Float.intBitsToFloat(vertexData[primitive + stride]) - refX;
+        val y2 = Float.intBitsToFloat(vertexData[primitive + stride + 1]) - refY;
+        val z2 = Float.intBitsToFloat(vertexData[primitive + stride + 2]) - refZ;
+        val x3 = Float.intBitsToFloat(vertexData[primitive + stride2]) - refX;
+        val y3 = Float.intBitsToFloat(vertexData[primitive + stride2 + 1]) - refY;
+        val z3 = Float.intBitsToFloat(vertexData[primitive + stride2 + 2]) - refZ;
+        val x4 = Float.intBitsToFloat(vertexData[primitive + stride3]) - refX;
+        val y4 = Float.intBitsToFloat(vertexData[primitive + stride3 + 1]) - refY;
+        val z4 = Float.intBitsToFloat(vertexData[primitive + stride3 + 2]) - refZ;
+
+        val x = (x1 + x2 + x3 + x4) * 0.25F;
+        val y = (y1 + y2 + y3 + y4) * 0.25F;
+        val z = (z1 + z2 + z3 + z4) * 0.25F;
+        return x * x + y * y + z * z;
+    }
+}

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

@@ -76,7 +76,8 @@ public enum Mixin implements IMixins {
                 "core.WorldRendererMixin")),
 
     VertexAPI(Phase.EARLY,
-              client("vertexapi.TessellatorMixin")),
+              client("vertexapi.TessellatorMixin",
+                     "vertexapi.QuadComparatorMixin")),
     VertexAPI_NoFoamFix(Phase.EARLY,
                         () -> !ModuleConfig.BSP_SORTING,
                         mods(avoid(FoamFix), avoid(SwanSong)),