Fix z-fighting for voidstone blocks

.gitignore

@@ -28,3 +28,4 @@ whitelist.json
 src/main/resources/mixins.*.json
 *.bat
 layout.json
+.DS_Store

gradle.properties

@@ -41,7 +41,7 @@ developmentEnvironmentUserName = Developer
 
 # Enables using modern Java syntax (up to version 17) via Jabel, while still targeting JVM 8.
 # See https://github.com/bsideup/jabel for details on how this works.
-enableModernJavaSyntax = false
+enableModernJavaSyntax = true
 
 # Enables injecting missing generics into the decompiled source code for a better coding experience.
 # Turns most publicly visible List, Map, etc. into proper List<E>, Map<K, V> types.

src/main/java/team/chisel/client/render/SubmapManagerVoidstone.java

@@ -21,91 +21,81 @@ public class SubmapManagerVoidstone extends SubmapManagerBase {
 
     // TODO there must be a better more generic way to do this...
     @SideOnly(Side.CLIENT)
-    private class RenderBlocksVoidstone extends RenderBlocksCTM {
+    private static class RenderBlocksVoidstone extends RenderBlocksCTM {
 
         @Override
         public void renderFaceXNeg(Block block, double x, double y, double z, IIcon icon) {
-            super.renderFaceXNeg(block, x, y, z, icon);
-            renderMinX += 0.005;
             setOverrideBlockTexture(getBase(x, y, z, ForgeDirection.WEST.ordinal()));
             super.renderFaceXNeg(block, x, y, z, null);
             clearOverrideBlockTexture();
+
+            super.renderFaceXNeg(block, x, y, z, icon);
         }
 
         @Override
         public void renderFaceXPos(Block block, double x, double y, double z, IIcon icon) {
-            super.renderFaceXPos(block, x, y, z, icon);
             setOverrideBlockTexture(getBase(x, y, z, ForgeDirection.EAST.ordinal()));
-            renderMaxX -= 0.005;
             super.renderFaceXPos(block, x, y, z, null);
             clearOverrideBlockTexture();
+
+            super.renderFaceXPos(block, x, y, z, icon);
         }
 
         @Override
         public void renderFaceYNeg(Block block, double x, double y, double z, IIcon icon) {
-            super.renderFaceYNeg(block, x, y, z, icon);
             setOverrideBlockTexture(getBase(x, y, z, ForgeDirection.DOWN.ordinal()));
-            renderMinY += 0.005;
             super.renderFaceYNeg(block, x, y, z, null);
             clearOverrideBlockTexture();
+
+            super.renderFaceYNeg(block, x, y, z, icon);
         }
 
         @Override
         public void renderFaceYPos(Block block, double x, double y, double z, IIcon icon) {
-            super.renderFaceYPos(block, x, y, z, icon);
             setOverrideBlockTexture(getBase(x, y, z, ForgeDirection.UP.ordinal()));
-            renderMaxY -= 0.005;
             super.renderFaceYPos(block, x, y, z, null);
             clearOverrideBlockTexture();
+
+            super.renderFaceYPos(block, x, y, z, icon);
         }
 
         @Override
         public void renderFaceZNeg(Block block, double x, double y, double z, IIcon icon) {
-            super.renderFaceZNeg(block, x, y, z, icon);
             setOverrideBlockTexture(getBase(x, y, z, ForgeDirection.NORTH.ordinal()));
-            renderMinZ += 0.005;
             super.renderFaceZNeg(block, x, y, z, null);
             clearOverrideBlockTexture();
+
+            super.renderFaceZNeg(block, x, y, z, icon);
         }
 
         @Override
         public void renderFaceZPos(Block block, double x, double y, double z, IIcon icon) {
-            super.renderFaceZPos(block, x, y, z, icon);
             setOverrideBlockTexture(getBase(x, y, z, ForgeDirection.SOUTH.ordinal()));
-            renderMaxZ -= 0.005;
             super.renderFaceZPos(block, x, y, z, null);
             clearOverrideBlockTexture();
+
+            super.renderFaceZPos(block, x, y, z, icon);
         }
 
-        public void reset() {
-            this.submap = null;
+        private IIcon getBase(double x, double y, double z, int side) {
+            return TextureType.getVIcon(
+                TextureType.V4,
+                base,
+                MathHelper.floor_double(x),
+                MathHelper.floor_double(y),
+                MathHelper.floor_double(z),
+                side);
         }
     }
 
     @SideOnly(Side.CLIENT)
     private static ThreadLocal<RenderBlocksVoidstone> renderBlocksThreadLocal;
 
-    private static void initStatics() {
-        if (renderBlocksThreadLocal == null) {
-            renderBlocksThreadLocal = new ThreadLocal<>();
-        }
-    }
-
     private ISubmapManager overlay;
-    private TextureSubmap base;
-
-    private IIcon getBase(double x, double y, double z, int side) {
-        return TextureType.getVIcon(
-            TextureType.V4,
-            base,
-            MathHelper.floor_double(x),
-            MathHelper.floor_double(y),
-            MathHelper.floor_double(z),
-            side);
-    }
+    private static TextureSubmap base;
 
-    private String texture;
-    private int meta;
+    private final String texture;
+    private final int meta;
 
     public SubmapManagerVoidstone(String texture, int meta) {
         this.texture = texture;
@@ -133,18 +123,22 @@ public void registerIcons(String modName, Block block, IIconRegister register) {
     @Override
     @SideOnly(Side.CLIENT)
     public RenderBlocks createRenderContext(RenderBlocks rendererOld, Block block, IBlockAccess world) {
-        initStatics();
+        if (renderBlocksThreadLocal == null) {
+            renderBlocksThreadLocal = ThreadLocal.withInitial(RenderBlocksVoidstone::new);
+        }
+
         RenderBlocksVoidstone rb = renderBlocksThreadLocal.get();
-        if (rb == null) {
-            rb = new RenderBlocksVoidstone();
-            renderBlocksThreadLocal.set(rb);
-        } else rb.reset();
         RenderBlocks ctx = overlay.createRenderContext(rendererOld, block, world);
         rb.setRenderBoundsFromBlock(block);
+
         if (ctx instanceof RenderBlocksCTM) {
             rb.submap = ((RenderBlocksCTM) ctx).submap;
             rb.submapSmall = ((RenderBlocksCTM) ctx).submapSmall;
+        } else {
+            rb.submap = null;
+            rb.submapSmall = null;
         }
+
         return rb;
     }
 }

src/main/java/team/chisel/ctmlib/RenderBlocksCTM.java

@@ -361,6 +361,61 @@ private int avg(int... lightVals) {
 
     protected void side(Block block, SubSide side, int iconIndex) {
 
+        // If we have an overridden texture when we're supposed to render a CTM texture,
+        // we'll treat it as a normal block texture but still render it the CTM way: quarter of a texture at a time.
+        // This way has one benefit: if an overridden texture is a base block texture and a CTM texture (that is being
+        // rendered next) is an overlay texture above the base, we're avoiding any z-fighting issues because we
+        // create identical vertices and now only order of rendering dictates which texture will be rendered above
+        if (hasOverrideBlockTexture()) {
+            IIcon icon = overrideBlockTexture;
+
+            double u0 = icon.getMinU();
+            double u1 = icon.getMaxU();
+            double v0 = icon.getMinV();
+            double v1 = icon.getMaxV();
+
+            double uMid = (u0 + u1) / 2;
+            double vMid = (v0 + v1) / 2;
+
+            // Map all LB-style subsides to bottom-left quarter, RB to bottom-right, RT to top-right, LT to top-left
+            switch (side) {
+                // bottom-left quarter
+                case XNEG_LB, XPOS_LB, YNEG_LB, YPOS_LB, ZNEG_LB, ZPOS_LB -> {
+                    minU = u0;
+                    maxU = uMid;
+                    minV = vMid;
+                    maxV = v1;
+                }
+
+                // bottom-right quarter
+                case XNEG_RB, XPOS_RB, YNEG_RB, YPOS_RB, ZNEG_RB, ZPOS_RB -> {
+                    minU = uMid;
+                    maxU = u1;
+                    minV = vMid;
+                    maxV = v1;
+                }
+
+                // top-right quarter
+                case XNEG_RT, XPOS_RT, YNEG_RT, YPOS_RT, ZNEG_RT, ZPOS_RT -> {
+                    minU = uMid;
+                    maxU = u1;
+                    minV = v0;
+                    maxV = vMid;
+                }
+
+                // top-left quarter
+                case XNEG_LT, XPOS_LT, YNEG_LT, YPOS_LT, ZNEG_LT, ZPOS_LT -> {
+                    minU = u0;
+                    maxU = uMid;
+                    minV = v0;
+                    maxV = vMid;
+                }
+            }
+
+            side.render(this);
+            return;
+        }
+
         IIcon icon;
         TextureSubmap map;
         if (iconIndex >= 16) {
@@ -378,33 +433,18 @@ protected void side(Block block, SubSide side, int iconIndex) {
             icon = map.getSubIcon(x, y);
         }
 
-        double umax = icon.getMaxU();
-        double umin = icon.getMinU();
-        double vmax = icon.getMaxV();
-        double vmin = icon.getMinV();
-
-        minU = umin;
-        maxU = umax;
-        minV = vmin;
-        maxV = vmax;
-
-        // uCache[0] = umin;
-        // uCache[1] = umax;
-        // uCache[2] = umax;
-        // uCache[3] = umin;
-        //
-        // vCache[0] = vmax;
-        // vCache[1] = vmax;
-        // vCache[2] = vmin;
-        // vCache[3] = vmin;
+        minU = icon.getMinU();
+        maxU = icon.getMaxU();
+        minV = icon.getMinV();
+        maxV = icon.getMaxV();
 
         side.render(this);
     }
 
     @Override
     public void renderFaceXNeg(Block block, double x, double y, double z, IIcon icon) {
         pre(ForgeDirection.WEST);
-        if (!inWorld || hasOverrideBlockTexture() || submap == null) {
+        if (!inWorld || submap == null) {
             super.renderFaceXNeg(block, 0, 0, 0, icon);
         } else {
             int tex[] = ctm.getSubmapIndices(blockAccess, bx, by, bz, 4);
@@ -429,7 +469,7 @@ public void renderFaceXNeg(Block block, double x, double y, double z, IIcon icon
     @Override
     public void renderFaceXPos(Block block, double x, double y, double z, IIcon icon) {
         pre(ForgeDirection.EAST);
-        if (!inWorld || hasOverrideBlockTexture() || submap == null) {
+        if (!inWorld || submap == null) {
             super.renderFaceXPos(block, 0, 0, 0, icon);
         } else {
             int tex[] = ctm.getSubmapIndices(blockAccess, bx, by, bz, 5);
@@ -454,7 +494,7 @@ public void renderFaceXPos(Block block, double x, double y, double z, IIcon icon
     @Override
     public void renderFaceZNeg(Block block, double x, double y, double z, IIcon icon) {
         pre(ForgeDirection.NORTH);
-        if (!inWorld || hasOverrideBlockTexture() || submap == null) {
+        if (!inWorld || submap == null) {
             super.renderFaceZNeg(block, 0, 0, 0, icon);
         } else {
             int tex[] = ctm.getSubmapIndices(blockAccess, bx, by, bz, 2);
@@ -479,7 +519,7 @@ public void renderFaceZNeg(Block block, double x, double y, double z, IIcon icon
     @Override
     public void renderFaceZPos(Block block, double x, double y, double z, IIcon icon) {
         pre(ForgeDirection.SOUTH);
-        if (!inWorld || hasOverrideBlockTexture() || submap == null) {
+        if (!inWorld || submap == null) {
             super.renderFaceZPos(block, 0, 0, 0, icon);
         } else {
             int tex[] = ctm.getSubmapIndices(blockAccess, bx, by, bz, 3);
@@ -504,7 +544,7 @@ public void renderFaceZPos(Block block, double x, double y, double z, IIcon icon
     @Override
     public void renderFaceYNeg(Block block, double x, double y, double z, IIcon icon) {
         pre(ForgeDirection.DOWN);
-        if (!inWorld || hasOverrideBlockTexture() || submap == null) {
+        if (!inWorld || submap == null) {
             super.renderFaceYNeg(block, 0, 0, 0, icon);
         } else {
             int tex[] = ctm.getSubmapIndices(blockAccess, bx, by, bz, 0);
@@ -529,7 +569,7 @@ public void renderFaceYNeg(Block block, double x, double y, double z, IIcon icon
     @Override
     public void renderFaceYPos(Block block, double x, double y, double z, IIcon icon) {
         pre(ForgeDirection.UP);
-        if (!inWorld || hasOverrideBlockTexture() || submap == null) {
+        if (!inWorld || submap == null) {
             super.renderFaceYPos(block, 0, 0, 0, icon);
         } else {
             int tex[] = ctm.getSubmapIndices(blockAccess, bx, by, bz, 1);