diff --git a/src/net/torvald/terrarum/worlddrawer/BlocksDrawer.kt b/src/net/torvald/terrarum/worlddrawer/BlocksDrawer.kt
index d6b491f16..c6c7c3e91 100644
--- a/src/net/torvald/terrarum/worlddrawer/BlocksDrawer.kt
+++ b/src/net/torvald/terrarum/worlddrawer/BlocksDrawer.kt
@@ -458,7 +458,7 @@ internal object BlocksDrawer {
                         (fillThis * 16f - 0.5f).floorToInt().coerceIn(0, 15)
                 }
                 else if (treeLeavesTiles.binarySearch(rawTileNum) >= 0) {
-                    getNearbyTilesInfoTrees(x, y, mode)//.swizzle8(rawTileNum, hash)
+                    getNearbyTilesInfoTrees(x, y, mode).swizzle8(rawTileNum, hash)
                 }
                 else if (treeTrunkTiles.binarySearch(rawTileNum) >= 0) {
                     hash = 0
@@ -466,17 +466,17 @@ internal object BlocksDrawer {
                 }
                 else if (platformTiles.binarySearch(rawTileNum) >= 0) {
                     hash %= 2
-                    getNearbyTilesInfoPlatform(x, y)//.swizzleH2(rawTileNum, hash)
+                    getNearbyTilesInfoPlatform(x, y).swizzleH2(rawTileNum, hash)
                 }
                 else if (wallStickerTiles.binarySearch(rawTileNum) >= 0) {
                     hash = 0
                     getNearbyTilesInfoWallSticker(x, y)
                 }
                 else if (connectMutualTiles.binarySearch(rawTileNum) >= 0) {
-                    getNearbyTilesInfoConMutual(x, y, mode)//.swizzle8(rawTileNum, hash)
+                    getNearbyTilesInfoConMutual(x, y, mode).swizzle8(rawTileNum, hash)
                 }
                 else if (connectSelfTiles.binarySearch(rawTileNum) >= 0) {
-                    getNearbyTilesInfoConSelf(x, y, mode, rawTileNum)//.swizzle8(rawTileNum, hash)
+                    getNearbyTilesInfoConSelf(x, y, mode, rawTileNum).swizzle8(rawTileNum, hash)
                 }
                 else {
                     0
@@ -521,10 +521,13 @@ internal object BlocksDrawer {
                 val breakingStage = if (mode == TERRAIN || mode == WALL || mode == ORES) (breakage / maxHealth).coerceIn(0f, 1f).times(BREAKAGE_STEPS).roundToInt() else 0
 
                 // draw a tile
-                writeToBuffer(mode, bufferBaseX*2+0, bufferBaseY*2+0, thisTileX+0, thisTileY+0, breakingStage, hash)
-                writeToBuffer(mode, bufferBaseX*2+1, bufferBaseY*2+0, thisTileX+1, thisTileY+0, breakingStage, hash)
-                writeToBuffer(mode, bufferBaseX*2+0, bufferBaseY*2+1, thisTileX+0, thisTileY+2, breakingStage, hash)
-                writeToBuffer(mode, bufferBaseX*2+1, bufferBaseY*2+1, thisTileX+1, thisTileY+2, breakingStage, hash)
+                val offsets = subtileOffsetsBySwizzleIndex[hash]
+                /*TL*/writeToBuffer(mode, bufferBaseX*2+offsets[0].x, bufferBaseY*2+offsets[0].y, thisTileX+0, thisTileY+0, breakingStage, hash)
+                /*TR*/writeToBuffer(mode, bufferBaseX*2+offsets[1].x, bufferBaseY*2+offsets[1].y, thisTileX+1, thisTileY+0, breakingStage, hash)
+                /*BR*/writeToBuffer(mode, bufferBaseX*2+offsets[2].x, bufferBaseY*2+offsets[2].y, thisTileX+1, thisTileY+2, breakingStage, hash)
+                /*BL*/writeToBuffer(mode, bufferBaseX*2+offsets[3].x, bufferBaseY*2+offsets[3].y, thisTileX+0, thisTileY+2, breakingStage, hash)
+
+
                 tempRenderTypeBuffer[bufferBaseY, bufferBaseX] = (nearbyTilesInfo or rawTileNum.shl(16)).toLong()
             }
         }
@@ -546,6 +549,30 @@ internal object BlocksDrawer {
         arrayOf(6,5,4,3,2,1,0,7), /* hfCW 270 */
     )
 
+    private val subtileOffsetsBySwizzleIndex = arrayOf(
+        // index: TL->TR->BR->BL
+        arrayOf(Point2i(0,0),Point2i(1,0),Point2i(1,1),Point2i(0,1)), /* normal */
+        arrayOf(Point2i(1,0),Point2i(0,0),Point2i(0,1),Point2i(1,1)), /* horz flip */
+        arrayOf(Point2i(1,0),Point2i(1,1),Point2i(0,1),Point2i(0,0)), /* CW 90 */
+        arrayOf(Point2i(0,0),Point2i(0,1),Point2i(1,1),Point2i(1,0)), /* hfCW 90 */
+        arrayOf(Point2i(1,1),Point2i(0,1),Point2i(0,0),Point2i(1,0)), /* CW 180 */
+        arrayOf(Point2i(0,1),Point2i(1,1),Point2i(1,0),Point2i(0,0)), /* hfCW 180 */
+        arrayOf(Point2i(0,1),Point2i(0,0),Point2i(1,0),Point2i(1,1)), /* CW 270 */
+        arrayOf(Point2i(1,1),Point2i(1,0),Point2i(0,0),Point2i(0,1)), /* hfCW 270 */
+    )
+
+    /*private val subtileOffsetsBySwizzleIndex = arrayOf(
+        // index: TL->TR->BR->BL
+        arrayOf(Point2i(0,0),Point2i(1,0),Point2i(1,1),Point2i(0,1)), /* normal */
+        arrayOf(Point2i(1,0),Point2i(0,0),Point2i(0,1),Point2i(1,1)), /* horz flip */
+        arrayOf(Point2i(0,1),Point2i(0,0),Point2i(1,0),Point2i(1,1)), /* CW 90 */
+        arrayOf(Point2i(1,1),Point2i(1,0),Point2i(0,0),Point2i(0,1)), /* hfCW 90 */
+        arrayOf(Point2i(1,1),Point2i(0,1),Point2i(0,0),Point2i(1,0)), /* CW 180 */
+        arrayOf(Point2i(0,1),Point2i(1,1),Point2i(1,0),Point2i(0,0)), /* hfCW 180 */
+        arrayOf(Point2i(1,0),Point2i(1,1),Point2i(0,1),Point2i(0,0)), /* CW 270 */
+        arrayOf(Point2i(0,0),Point2i(0,1),Point2i(1,1),Point2i(1,0)), /* hfCW 270 */
+    )*/
+
     private fun Int.swizzle8(tile: Int, hash: Int): Int {
         var ret = 0
         swizzleMap8[hash].forEachIndexed { index, ord ->
diff --git a/src/shaders/tiling.frag b/src/shaders/tiling.frag
index 53587c164..0428c76bb 100644
--- a/src/shaders/tiling.frag
+++ b/src/shaders/tiling.frag
@@ -1,7 +1,3 @@
-/*
-
-*/
-
 
 #ifdef GL_ES
 precision mediump float;
@@ -44,8 +40,15 @@ const vec2 haalf = vec2(0.5, 0.5);
 
 out vec4 fragColor;
 
-ivec2 tileNumberToXY(int tileNumber) {
-    return ivec2(tileNumber % int(tilesInAtlas.x), tileNumber / int(tilesInAtlas.x));
+ivec4 tileNumberToXY(int tileNumber) {
+    int tileX = tileNumber % int(tilesInAtlas.x);
+    int tileY = tileNumber / int(tilesInAtlas.x);
+    return ivec4(
+        tileX, // tileX
+        tileY, // tileY
+        tileX % 2, // quadrant-x (0, 1)
+        tileY % 2 // quadrant-y (0, 1)
+    );
 }
 
 // return: ivec3(tileID, breakage, fliprot)
@@ -62,8 +65,8 @@ ivec3 _colToInt(vec4 map1, vec4 map2) {
 
     return ivec3(
         (col1.r << 16) | (col1.g << 8) | col1.b, // tile
-        0,//col2.b, // breakage
-        0//col2.g // fliprot
+        col2.b, // breakage
+        col2.g // fliprot
     );
 }
 
@@ -103,8 +106,12 @@ void main() {
     int tile = tbf.x;
     int breakage = tbf.y;
     int flipRot = tbf.z;
-    ivec2 tileXY = tileNumberToXY(tile);
-    ivec2 breakageXY = tileNumberToXY(breakage + 5); // +5 is hard-coded constant that depends on the contents of the atlas
+    ivec4 tileXYnQ = tileNumberToXY(tile);
+    ivec4 breakageXYnQ = tileNumberToXY(breakage + 5); // +5 is hard-coded constant that depends on the contents of the atlas
+    ivec2 tileXY = tileXYnQ.xy;
+    ivec2 tileQ = tileXYnQ.zw;
+    ivec2 breakageXY = breakageXYnQ.xy;
+    ivec2 breakageQ = breakageXYnQ.zw;
 
     // calculate the UV coord value for texture sampling //
 
@@ -130,11 +137,13 @@ void main() {
     vec4 finalColor = fma(mix(finalTile, finalBreakage, finalBreakage.a), bc.xxxy, finalTile * bc.yyyx);
 
 //    fragColor = mix(colourFilter, colourFilter * finalColor, mulBlendIntensity);
-    fragColor = finalTile;
+
+    vec4 quadrantOverlay = vec4(tileQ.x, tileQ.y, 0.0, 1.0);
+    fragColor = finalTile;// * quadrantOverlay;
 
 
     // SUBTILE fixme:
     // - breakage tile samples wrong coord -- needs bigtile-to-subtile adaptation
-    // - somehow make fliprot work again -- needs bigtile-to-subtile adaptation
+    // - figure out which quadrant the tile is in -- legacy support
 
 }