Update app.py

app.py

@@ -481,7 +481,7 @@ def process_image_and_generate_stl(image_input, depth_near, depth_far, thickness
     preview_path = stl_path.replace(".stl", "_preview.stl")
     mesh = trimesh.load(stl_path)
     rot = trimesh.transformations.rotation_matrix(np.radians(180), [0, 0, 1])
-    rot2 = trimesh.transformations.rotation_matrix(np.radians(-90),[0, 1, 0])
+    rot2 = trimesh.transformations.rotation_matrix(np.radians(-90),[1, 0, 0])
     mesh.apply_transform(rot)
     mesh.apply_transform(rot2)
     mesh.export(preview_path)