diff --git a/io_scene_gltf2/__init__.py b/io_scene_gltf2/__init__.py
index daa6c7e42171d5e88f3eb083e216afbc250c1a26..60a9a52c33e53c4274ed499f5a1bfde7a12a8e23 100755
--- a/io_scene_gltf2/__init__.py
+++ b/io_scene_gltf2/__init__.py
@@ -15,7 +15,7 @@
bl_info = {
'name': 'glTF 2.0 format',
'author': 'Julien Duroure, Scurest, Norbert Nopper, Urs Hanselmann, Moritz Becher, Benjamin SchmithĂĽsen, Jim Eckerlein, and many external contributors',
- "version": (1, 4, 9),
+ "version": (1, 4, 10),
'blender': (2, 90, 0),
'location': 'File > Import-Export',
'description': 'Import-Export as glTF 2.0',
diff --git a/io_scene_gltf2/blender/imp/gltf2_blender_mesh.py b/io_scene_gltf2/blender/imp/gltf2_blender_mesh.py
index e13b9c8fab3198b7c1c379a6302be79a9e178b0b..3337215feb6ac9277839c6b9fa4fe6888083e537 100755
--- a/io_scene_gltf2/blender/imp/gltf2_blender_mesh.py
+++ b/io_scene_gltf2/blender/imp/gltf2_blender_mesh.py
@@ -352,32 +352,8 @@ def do_primitives(gltf, mesh_idx, skin_idx, mesh, ob):
# ----
# Normals
- # Set poly smoothing
- # TODO: numpyify?
- smooths = [] # use_smooth for each poly
- f = 0
- for prim in pymesh.primitives:
- if gltf.import_settings['import_shading'] == "FLAT" or \
- 'NORMAL' not in prim.attributes:
- smooths += [False] * prim.num_faces
-
- elif gltf.import_settings['import_shading'] == "SMOOTH":
- smooths += [True] * prim.num_faces
-
- elif gltf.import_settings['import_shading'] == "NORMALS":
- for fi in range(f, f + prim.num_faces):
- # Make the face flat if the face's normal is
- # equal to all of its loops' normals.
- poly_normal = mesh.polygons[fi].normal
- smooths.append(
- poly_normal.dot(vert_normals[loop_vidxs[3*fi + 0]]) <= 0.9999999 or
- poly_normal.dot(vert_normals[loop_vidxs[3*fi + 1]]) <= 0.9999999 or
- poly_normal.dot(vert_normals[loop_vidxs[3*fi + 2]]) <= 0.9999999
- )
-
- f += prim.num_faces
-
- mesh.polygons.foreach_set('use_smooth', smooths)
+ # Set polys smooth/flat
+ set_poly_smoothing(gltf, pymesh, mesh, vert_normals, loop_vidxs)
mesh.validate()
has_loose_edges = len(edge_vidxs) != 0 # need to calc_loose_edges for them to show up
@@ -553,6 +529,69 @@ def normalize_vecs(vectors):
np.divide(vectors, norms, out=vectors, where=norms != 0)
+def set_poly_smoothing(gltf, pymesh, mesh, vert_normals, loop_vidxs):
+ num_polys = len(mesh.polygons)
+
+ if gltf.import_settings['import_shading'] == "FLAT":
+ # Polys are flat by default; don't have to do anything
+ return
+
+ if gltf.import_settings['import_shading'] == "SMOOTH":
+ poly_smooths = np.full(num_polys, True)
+ f = 0
+ for prim in pymesh.primitives:
+ if 'NORMAL' not in prim.attributes:
+ # Primitives with no NORMALs should use flat shading
+ poly_smooths[f:f + prim.num_faces].fill(False)
+ f += prim.num_faces
+ mesh.polygons.foreach_set('use_smooth', poly_smooths)
+ return
+
+ assert gltf.import_settings['import_shading'] == "NORMALS"
+
+ # Try to guess which polys should be flat based on the fact that all the
+ # loop normals for a flat poly are = the poly's normal.
+
+ poly_smooths = np.empty(num_polys, dtype=np.bool)
+
+ poly_normals = np.empty(num_polys * 3, dtype=np.float32)
+ mesh.polygons.foreach_get('normal', poly_normals)
+ poly_normals = poly_normals.reshape(num_polys, 3)
+
+ f = 0
+ for prim in pymesh.primitives:
+ if 'NORMAL' not in prim.attributes:
+ # Primitives with no NORMALs should use flat shading
+ poly_smooths[f:f + prim.num_faces].fill(False)
+ f += prim.num_faces
+ continue
+
+ # Check the normals at the three corners against the poly normal.
+ # Two normals are equal iff their dot product is 1.
+
+ poly_ns = poly_normals[f:f + prim.num_faces]
+
+ # Dot product against the first vertex normal in the tri
+ vert_ns = vert_normals[loop_vidxs[3*f:3*(f + prim.num_faces):3]]
+ dot_prods = np.sum(vert_ns * poly_ns, axis=1) # dot product
+ smooth = (dot_prods <= 0.9999999)
+
+ # Same for the second vertex, etc.
+ vert_ns = vert_normals[loop_vidxs[3*f+1:3*(f + prim.num_faces):3]]
+ dot_prods = np.sum(vert_ns * poly_ns, axis=1)
+ np.logical_or(smooth, dot_prods <= 0.9999999, out=smooth)
+
+ vert_ns = vert_normals[loop_vidxs[3*f+2:3*(f + prim.num_faces):3]]
+ dot_prods = np.sum(vert_ns * poly_ns, axis=1)
+ np.logical_or(smooth, dot_prods <= 0.9999999, out=smooth)
+
+ poly_smooths[f:f + prim.num_faces] = smooth
+
+ f += prim.num_faces
+
+ mesh.polygons.foreach_set('use_smooth', poly_smooths)
+
+
def merge_duplicate_verts(vert_locs, vert_normals, vert_joints, vert_weights, sk_vert_locs, loop_vidxs, edge_vidxs):
# This function attempts to invert the splitting done when exporting to
# glTF. Welds together verts with the same per-vert data (but possibly