diff --git a/assets/index.html b/assets/index.html
index e2f6433..707a4df 100644
--- a/assets/index.html
+++ b/assets/index.html
@@ -71,7 +71,7 @@
         }
     }
 
-    function drawTile(wx, wy, h, water, hLeft, hFront) {
+    function drawTile(wx, wy, h, water, hRight, hBack) {
         var top1 = project(wx + GAP/2, wy + TILE - GAP/2, h * HEIGHT_UNIT);
         var top2 = project(wx + TILE - GAP/2, wy + TILE - GAP/2, h * HEIGHT_UNIT);
         var top3 = project(wx + TILE - GAP/2, wy + GAP/2, h * HEIGHT_UNIT);
@@ -90,24 +90,24 @@
         ctx.closePath();
         ctx.fill();
 
-        if (hLeft < h) {
-            ctx.fillStyle = leftColor;
+        if (hRight < h) {
+            ctx.fillStyle = rightColor;
             ctx.beginPath();
-            ctx.moveTo(top4[0], top4[1]);
-            ctx.lineTo(top1[0], top1[1]);
-            ctx.lineTo(top1[0], top1[1] + (h - hLeft) * HEIGHT_UNIT);
-            ctx.lineTo(top4[0], top4[1] + (h - hLeft) * HEIGHT_UNIT);
+            ctx.moveTo(top2[0], top2[1]);
+            ctx.lineTo(top3[0], top3[1]);
+            ctx.lineTo(top3[0], top3[1] + (h - hRight) * HEIGHT_UNIT);
+            ctx.lineTo(top2[0], top2[1] + (h - hRight) * HEIGHT_UNIT);
             ctx.closePath();
             ctx.fill();
         }
 
-        if (hFront < h) {
-            ctx.fillStyle = rightColor;
+        if (hBack < h) {
+            ctx.fillStyle = leftColor;
             ctx.beginPath();
-            ctx.moveTo(top3[0], top3[1]);
-            ctx.lineTo(top4[0], top4[1]);
-            ctx.lineTo(top4[0], top4[1] + (h - hFront) * HEIGHT_UNIT);
-            ctx.lineTo(top3[0], top3[1] + (h - hFront) * HEIGHT_UNIT);
+            ctx.moveTo(top1[0], top1[1]);
+            ctx.lineTo(top2[0], top2[1]);
+            ctx.lineTo(top2[0], top2[1] + (h - hBack) * HEIGHT_UNIT);
+            ctx.lineTo(top1[0], top1[1] + (h - hBack) * HEIGHT_UNIT);
             ctx.closePath();
             ctx.fill();
         }
@@ -130,10 +130,10 @@
 
             var water = isWater(h);
 
-            var hLeft = heightMap[(wx - TILE) + ',' + wy] || 0;
-            var hFront = heightMap[wx + ',' + (wy - TILE)] || 0;
+            var hRight = heightMap[(wx + TILE) + ',' + wy] || 0;
+            var hBack = heightMap[wx + ',' + (wy + TILE)] || 0;
 
-            drawTile(wx, wy, h, water, hLeft, hFront);
+            drawTile(wx, wy, h, water, hRight, hBack);
         }
     }