Fix black texture bug: add _clean_invalid_vertices after cumesh.fill_holes()

o-voxel/o_voxel/postprocess.py

@@ -11,6 +11,31 @@ import nvdiffrast.torch as dr
 import cumesh
 
 
+def _clean_invalid_vertices(mesh, vertices, faces, aabb, verbose=False):
+    """
+    Workaround for cumesh.fill_holes() bug that creates vertices with garbage positions.
+    Removes vertices and faces that are outside the valid AABB bounds.
+    """
+    valid_mask = (vertices.min(dim=1)[0] >= aabb[0].min() - 1.0) & (vertices.max(dim=1)[0] <= aabb[1].max() + 1.0)
+    if not valid_mask.all():
+        invalid_count = (~valid_mask).sum().item()
+        if verbose:
+            print(f"  [CLEANUP] Removing {invalid_count} vertices with invalid positions")
+        # Remove faces that reference invalid vertices
+        invalid_verts = torch.where(~valid_mask)[0]
+        valid_faces_mask = ~torch.isin(faces, invalid_verts).any(dim=1)
+        faces = faces[valid_faces_mask]
+        # Compact vertices - renumber faces to match new vertex indices
+        valid_indices = torch.where(valid_mask)[0]
+        remap = torch.zeros(vertices.shape[0], dtype=torch.int32, device=vertices.device)
+        remap[valid_indices] = torch.arange(valid_indices.shape[0], dtype=torch.int32, device=vertices.device)
+        vertices = vertices[valid_mask]
+        faces = remap[faces.long()].int()
+        # Reinitialize mesh with cleaned data
+        mesh.init(vertices, faces)
+    return vertices, faces
+
+
 def to_glb(
     vertices: torch.Tensor,
     faces: torch.Tensor,
@@ -111,6 +136,7 @@ def to_glb(
     if verbose:
         print(f"After filling holes: {mesh.num_vertices} vertices, {mesh.num_faces} faces")
     vertices, faces = mesh.read()
+    vertices, faces = _clean_invalid_vertices(mesh, vertices, faces, aabb, verbose)
     if use_tqdm:
         pbar.update(1)
         
@@ -142,19 +168,23 @@ def to_glb(
         mesh.repair_non_manifold_edges()
         mesh.remove_small_connected_components(1e-5)
         mesh.fill_holes(max_hole_perimeter=3e-2)
+        vertices_tmp, faces_tmp = mesh.read()
+        vertices_tmp, faces_tmp = _clean_invalid_vertices(mesh, vertices_tmp, faces_tmp, aabb, verbose)
         if verbose:
             print(f"After initial cleanup: {mesh.num_vertices} vertices, {mesh.num_faces} faces")
-            
+
         # Step 3: Final simplification to target count
         mesh.simplify(decimation_target, verbose=verbose)
         if verbose:
             print(f"After final simplification: {mesh.num_vertices} vertices, {mesh.num_faces} faces")
-        
+
         # Step 4: Final Cleanup loop
         mesh.remove_duplicate_faces()
         mesh.repair_non_manifold_edges()
         mesh.remove_small_connected_components(1e-5)
         mesh.fill_holes(max_hole_perimeter=3e-2)
+        vertices_tmp, faces_tmp = mesh.read()
+        vertices_tmp, faces_tmp = _clean_invalid_vertices(mesh, vertices_tmp, faces_tmp, aabb, verbose)
         if verbose:
             print(f"After final cleanup: {mesh.num_vertices} vertices, {mesh.num_faces} faces")