Applied xatlas - Meshes without UVs are also accepted

README.md

@@ -79,7 +79,7 @@ For the best quality of texture synthesis, there are some necessary pre-processi
 
 We provide `scripts/normalize_mesh.py` and `scripts/rotate_mesh.py` to make the mesh preprocessing easy for you.
 
-If you already have a normalized mesh but haven't parameterized it yet, please use `scripts/parameterize_mesh.py` to generate the UV map.
+~~If you already have a normalized mesh but haven't parameterized it yet, please use `scripts/parameterize_mesh.py` to generate the UV map.~~ Now, you don't have to parameterize your mesh by yourself thanks to [xatlas](https://github.com/jpcy/xatlas).
 
 > NOTE: we expect the mesh to be triangulated.
 

lib/mesh_helper.py

@@ -1,6 +1,7 @@
 import os
 import torch
 import trimesh
+import xatlas
 
 import numpy as np
 
@@ -27,14 +28,26 @@ def compute_principle_directions(model_path, num_points=20000):
     return principle_directions
 
 
-def init_mesh(model_path, device):
+def init_mesh(input_path, cache_path, device):
+    print("=> parameterizing target mesh...")
+
+    mesh = trimesh.load_mesh(input_path, force='mesh')
+    try:
+        vertices, faces = mesh.vertices, mesh.faces
+    except AttributeError:
+        print("multiple materials in {} are not supported".format(input_path))
+        exit()
+
+    vmapping, indices, uvs = xatlas.parametrize(vertices, faces)
+    xatlas.export(str(cache_path), vertices[vmapping], indices, uvs)
+
     print("=> loading target mesh...")
 
-    # principle_directions = compute_principle_directions(model_path)
+    # principle_directions = compute_principle_directions(cache_path)
     principle_directions = None
 
-    _, faces, aux = load_obj(model_path, device=device)
-    mesh = load_objs_as_meshes([model_path], device=device)
+    _, faces, aux = load_obj(cache_path, device=device)
+    mesh = load_objs_as_meshes([cache_path], device=device)
 
     num_verts = mesh.verts_packed().shape[0]
 

scripts/generate_texture.py

@@ -184,7 +184,11 @@ def init_args():
 
     # init resources
     # init mesh
-    mesh, _, faces, aux, principle_directions, mesh_center, mesh_scale = init_mesh(os.path.join(args.input_dir, args.obj_file), DEVICE)
+    mesh, _, faces, aux, principle_directions, mesh_center, mesh_scale = init_mesh(
+        os.path.join(args.input_dir, args.obj_file),
+        os.path.join(output_dir, args.obj_file), 
+        DEVICE
+    )
 
     # gradient texture
     init_texture = Image.open("./samples/textures/dummy.png").convert("RGB").resize((args.uv_size, args.uv_size))