diff --git a/vendor/clouds3d.js b/vendor/clouds3d.js
index 60b92b2..9e620c7 100644
--- a/vendor/clouds3d.js
+++ b/vendor/clouds3d.js
@@ -346,12 +346,12 @@ function drawTileAt(lng, perp, dx, dz, centerTileX, centerTileY) {
         // (canvasX + 256, canvasY + 256). After this, image north
         // (high lat) is at canvas bottom and image south at canvas
         // top; image east at canvas right, image west at canvas left.
-        // Flip image 180° (both X and Y). Image top (north) -> canvas
-        // bottom, image bottom (south) -> canvas top, image left
-        // (west) -> canvas right, image right (east) -> canvas left.
-        // Labels N/S already match the Y-flipped orientation.
-        groundCtx.drawImage(img, canvasX + GROUND_TILE_SIZE, canvasY + GROUND_TILE_SIZE,
-            -GROUND_TILE_SIZE, -GROUND_TILE_SIZE);
+        // Mirror image across the NS axis (X-only flip). Image top
+        // (north) stays at canvas top, image bottom (south) stays
+        // at canvas bottom. Image left (west) -> canvas right, image
+        // right (east) -> canvas left.
+        groundCtx.drawImage(img, canvasX + GROUND_TILE_SIZE, canvasY,
+            -GROUND_TILE_SIZE, GROUND_TILE_SIZE);
         groundLoadedTiles[tileX + '_' + tileY] = true;
 
         // Debug labels: 'N' at the image's north edge (top of canvas
@@ -363,13 +363,12 @@ function drawTileAt(lng, perp, dx, dz, centerTileX, centerTileY) {
         groundCtx.lineWidth = 3;
         groundCtx.font = 'bold 48px sans-serif';
         groundCtx.textAlign = 'center';
-        // N at canvas bottom of tile area (image north is at canvas
-        // bottom because image is Y-flipped).
-        groundCtx.strokeText('N', canvasX + 128, canvasY + 240);
-        groundCtx.fillText('N', canvasX + 128, canvasY + 240);
-        // S at canvas top
-        groundCtx.strokeText('S', canvasX + 128, canvasY + 56);
-        groundCtx.fillText('S', canvasX + 128, canvasY + 56);
+        // N at canvas top of tile area (image north is at top)
+        groundCtx.strokeText('N', canvasX + 128, canvasY + 56);
+        groundCtx.fillText('N', canvasX + 128, canvasY + 56);
+        // S at canvas bottom
+        groundCtx.strokeText('S', canvasX + 128, canvasY + 240);
+        groundCtx.fillText('S', canvasX + 128, canvasY + 240);
         // Tile coords
         groundCtx.font = 'bold 20px monospace';
         groundCtx.strokeText('x=' + tileX + ' y=' + tileY,