glTF importer: fix material import / vertex color

Fixed a bug when a same material sometimes uses vertex color, sometimes doesn't

7 files changed, 57 insertions, 38 deletions

diff --git a/io_scene_gltf2/blender/imp/gltf2_blender_gltf.py b/io_scene_gltf2/blender/imp/gltf2_blender_gltf.py
index 9afc12de..1f708b40 100755
--- a/io_scene_gltf2/blender/imp/gltf2_blender_gltf.py
+++ b/io_scene_gltf2/blender/imp/gltf2_blender_gltf.py
@@ -84,7 +84,7 @@ class BlenderGlTF():
         # Blender material
         if gltf.data.materials:
             for material in gltf.data.materials:
-                material.blender_material = None
+                material.blender_material = {}
 
                 if material.pbr_metallic_roughness:
                     # Init
diff --git a/io_scene_gltf2/blender/imp/gltf2_blender_map_emissive.py b/io_scene_gltf2/blender/imp/gltf2_blender_map_emissive.py
index 81cfd76e..c3d0cb22 100755
--- a/io_scene_gltf2/blender/imp/gltf2_blender_map_emissive.py
+++ b/io_scene_gltf2/blender/imp/gltf2_blender_map_emissive.py
@@ -23,17 +23,17 @@ class BlenderEmissiveMap():
         raise RuntimeError("%s should not be instantiated" % cls)
 
     @staticmethod
-    def create(gltf, material_idx):
+    def create(gltf, material_idx, vertex_color):
         """Create emissive map."""
         engine = bpy.context.scene.render.engine
         if engine in ['CYCLES', 'BLENDER_EEVEE']:
-            BlenderEmissiveMap.create_nodetree(gltf, material_idx)
+            BlenderEmissiveMap.create_nodetree(gltf, material_idx, vertex_color)
 
-    def create_nodetree(gltf, material_idx):
+    def create_nodetree(gltf, material_idx, vertex_color):
         """Create node tree."""
         pymaterial = gltf.data.materials[material_idx]
 
-        material = bpy.data.materials[pymaterial.blender_material]
+        material = bpy.data.materials[pymaterial.blender_material[vertex_color]]
         node_tree = material.node_tree
 
         BlenderTextureInfo.create(gltf, pymaterial.emissive_texture.index)
diff --git a/io_scene_gltf2/blender/imp/gltf2_blender_map_normal.py b/io_scene_gltf2/blender/imp/gltf2_blender_map_normal.py
index ab09f24c..0f7bab81 100755
--- a/io_scene_gltf2/blender/imp/gltf2_blender_map_normal.py
+++ b/io_scene_gltf2/blender/imp/gltf2_blender_map_normal.py
@@ -22,17 +22,17 @@ class BlenderNormalMap():
         raise RuntimeError("%s should not be instantiated" % cls)
 
     @staticmethod
-    def create(gltf, material_idx):
+    def create(gltf, material_idx, vertex_color):
         """Creation of Normal map."""
         engine = bpy.context.scene.render.engine
         if engine in ['CYCLES', 'BLENDER_EEVEE']:
-            BlenderNormalMap.create_nodetree(gltf, material_idx)
+            BlenderNormalMap.create_nodetree(gltf, material_idx, vertex_color)
 
-    def create_nodetree(gltf, material_idx):
+    def create_nodetree(gltf, material_idx, vertex_color):
         """Creation of Nodetree."""
         pymaterial = gltf.data.materials[material_idx]
 
-        material = bpy.data.materials[pymaterial.blender_material]
+        material = bpy.data.materials[pymaterial.blender_material[vertex_color]]
         node_tree = material.node_tree
 
         BlenderTextureInfo.create(gltf, pymaterial.normal_texture.index)
diff --git a/io_scene_gltf2/blender/imp/gltf2_blender_map_occlusion.py b/io_scene_gltf2/blender/imp/gltf2_blender_map_occlusion.py
index 5c41ce9e..70e1e54a 100755
--- a/io_scene_gltf2/blender/imp/gltf2_blender_map_occlusion.py
+++ b/io_scene_gltf2/blender/imp/gltf2_blender_map_occlusion.py
@@ -22,13 +22,13 @@ class BlenderOcclusionMap():
         raise RuntimeError("%s should not be instantiated" % cls)
 
     @staticmethod
-    def create(gltf, material_idx):
+    def create(gltf, material_idx, vertex_color):
         """Occlusion map creation."""
         engine = bpy.context.scene.render.engine
         if engine in ['CYCLES', 'BLENDER_EEVEE']:
-            BlenderOcclusionMap.create_nodetree(gltf, material_idx)
+            BlenderOcclusionMap.create_nodetree(gltf, material_idx, vertex_color)
 
-    def create_nodetree(gltf, material_idx):
+    def create_nodetree(gltf, material_idx, vertex_color):
         """Nodetree creation."""
         pymaterial = gltf.data.materials[material_idx]
 
diff --git a/io_scene_gltf2/blender/imp/gltf2_blender_material.py b/io_scene_gltf2/blender/imp/gltf2_blender_material.py
index c9fa6927..c910b7f8 100755
--- a/io_scene_gltf2/blender/imp/gltf2_blender_material.py
+++ b/io_scene_gltf2/blender/imp/gltf2_blender_material.py
@@ -34,13 +34,19 @@ class BlenderMaterial():
         """Material creation."""
         pymaterial = gltf.data.materials[material_idx]
 
-        if pymaterial.name is not None:
-            name = pymaterial.name
+        if vertex_color is None:
+            if pymaterial.name is not None:
+                name = pymaterial.name
+            else:
+                name = "Material_" + str(material_idx)
         else:
-            name = "Material_" + str(material_idx)
+            if pymaterial.name is not None:
+                name = pymaterial.name + "_" + vertex_color
+            else:
+                name = "Material_" + str(material_idx) + "_" + vertex_color
 
         mat = bpy.data.materials.new(name)
-        pymaterial.blender_material = mat.name
+        pymaterial.blender_material[vertex_color] = mat.name
 
         if pymaterial.extensions is not None and 'KHR_materials_pbrSpecularGlossiness' in pymaterial.extensions.keys():
             BlenderKHR_materials_pbrSpecularGlossiness.create(
@@ -62,36 +68,36 @@ class BlenderMaterial():
 
         # add emission map if needed
         if pymaterial.emissive_texture is not None:
-            BlenderEmissiveMap.create(gltf, material_idx)
+            BlenderEmissiveMap.create(gltf, material_idx, vertex_color)
 
         # add normal map if needed
         if pymaterial.normal_texture is not None:
-            BlenderNormalMap.create(gltf, material_idx)
+            BlenderNormalMap.create(gltf, material_idx, vertex_color)
 
         # add occlusion map if needed
         # will be pack, but not used
         if pymaterial.occlusion_texture is not None:
-            BlenderOcclusionMap.create(gltf, material_idx)
+            BlenderOcclusionMap.create(gltf, material_idx, vertex_color)
 
         if pymaterial.alpha_mode is not None and pymaterial.alpha_mode != 'OPAQUE':
-            BlenderMaterial.blender_alpha(gltf, material_idx)
+            BlenderMaterial.blender_alpha(gltf, material_idx, vertex_color)
 
     @staticmethod
-    def set_uvmap(gltf, material_idx, prim, obj):
+    def set_uvmap(gltf, material_idx, prim, obj, vertex_color):
         """Set UV Map."""
         pymaterial = gltf.data.materials[material_idx]
 
-        node_tree = bpy.data.materials[pymaterial.blender_material].node_tree
+        node_tree = bpy.data.materials[pymaterial.blender_material[vertex_color]].node_tree
         uvmap_nodes = [node for node in node_tree.nodes if node.type in ['UVMAP', 'NORMAL_MAP']]
         for uvmap_node in uvmap_nodes:
             if uvmap_node["gltf2_texcoord"] in prim.blender_texcoord.keys():
                 uvmap_node.uv_map = prim.blender_texcoord[uvmap_node["gltf2_texcoord"]]
 
     @staticmethod
-    def blender_alpha(gltf, material_idx):
+    def blender_alpha(gltf, material_idx, vertex_color):
         """Set alpha."""
         pymaterial = gltf.data.materials[material_idx]
-        material = bpy.data.materials[pymaterial.blender_material]
+        material = bpy.data.materials[pymaterial.blender_material[vertex_color]]
 
         node_tree = material.node_tree
         # Add nodes for basic transparency
diff --git a/io_scene_gltf2/blender/imp/gltf2_blender_mesh.py b/io_scene_gltf2/blender/imp/gltf2_blender_mesh.py
index f0d0af2a..2d346638 100755
--- a/io_scene_gltf2/blender/imp/gltf2_blender_mesh.py
+++ b/io_scene_gltf2/blender/imp/gltf2_blender_mesh.py
@@ -79,7 +79,10 @@ class BlenderMesh():
 
         # Object and UV are now created, we can set UVMap into material
         for prim in pymesh.primitives:
-            BlenderPrimitive.set_UV_in_mat(gltf, prim, obj)
+            vertex_color = None
+            if 'COLOR_0' in prim.attributes.keys():
+                vertex_color = 'COLOR_0'
+            BlenderPrimitive.set_UV_in_mat(gltf, prim, obj, vertex_color)
 
         # Assign materials to mesh
         offset = 0
diff --git a/io_scene_gltf2/blender/imp/gltf2_blender_primitive.py b/io_scene_gltf2/blender/imp/gltf2_blender_primitive.py
index 52987383..93bab542 100755
--- a/io_scene_gltf2/blender/imp/gltf2_blender_primitive.py
+++ b/io_scene_gltf2/blender/imp/gltf2_blender_primitive.py
@@ -57,13 +57,18 @@ class BlenderPrimitive():
         # manage material of primitive
         if pyprimitive.material is not None:
 
-            # Create Blender material
-            # TODO, a same material can have difference COLOR_0 multiplicator
-            if gltf.data.materials[pyprimitive.material].blender_material is None:
-                vertex_color = None
-                if 'COLOR_0' in pyprimitive.attributes.keys():
-                    vertex_color = pyprimitive.attributes['COLOR_0']
-                BlenderMaterial.create(gltf, pyprimitive.material, vertex_color)
+            vertex_color = None
+            if 'COLOR_0' in pyprimitive.attributes.keys():
+                vertex_color = 'COLOR_0'
+
+            # Create Blender material if needed
+            if vertex_color is None:
+                if None not in gltf.data.materials[pyprimitive.material].blender_material.keys():
+                    BlenderMaterial.create(gltf, pyprimitive.material, vertex_color)
+            else:
+                if vertex_color not in gltf.data.materials[pyprimitive.material].blender_material.keys():
+                    BlenderMaterial.create(gltf, pyprimitive.material, vertex_color)
+
 
         return verts, edges, faces
 
@@ -126,7 +131,7 @@ class BlenderPrimitive():
         offset = offset + pyprimitive.vertices_length
         return offset
 
-    def set_UV_in_mat(gltf, pyprimitive, obj):
+    def set_UV_in_mat(gltf, pyprimitive, obj, vertex_color):
         """After nodetree creation, set UVMap in nodes."""
         if pyprimitive.material is None:
             return
@@ -137,29 +142,34 @@ class BlenderPrimitive():
                     and gltf.data.materials[pyprimitive.material].extensions[
                         'KHR_materials_pbrSpecularGlossiness'
                     ]['diffuse_type'] in [gltf.TEXTURE, gltf.TEXTURE_FACTOR]:
-                BlenderMaterial.set_uvmap(gltf, pyprimitive.material, pyprimitive, obj)
+                BlenderMaterial.set_uvmap(gltf, pyprimitive.material, pyprimitive, obj, vertex_color)
             else:
                 if pyprimitive.material is not None \
                         and gltf.data.materials[pyprimitive.material].extensions[
                             'KHR_materials_pbrSpecularGlossiness'
                         ]['specgloss_type'] in [gltf.TEXTURE, gltf.TEXTURE_FACTOR]:
-                    BlenderMaterial.set_uvmap(gltf, pyprimitive.material, pyprimitive, obj)
+                    BlenderMaterial.set_uvmap(gltf, pyprimitive.material, pyprimitive, obj, vertex_color)
 
         else:
             if pyprimitive.material is not None \
                     and gltf.data.materials[pyprimitive.material].pbr_metallic_roughness.color_type in \
                     [gltf.TEXTURE, gltf.TEXTURE_FACTOR]:
-                BlenderMaterial.set_uvmap(gltf, pyprimitive.material, pyprimitive, obj)
+                BlenderMaterial.set_uvmap(gltf, pyprimitive.material, pyprimitive, obj, vertex_color)
             else:
                 if pyprimitive.material is not None \
                         and gltf.data.materials[pyprimitive.material].pbr_metallic_roughness.metallic_type in \
                         [gltf.TEXTURE, gltf.TEXTURE_FACTOR]:
-                    BlenderMaterial.set_uvmap(gltf, pyprimitive.material, pyprimitive, obj)
+                    BlenderMaterial.set_uvmap(gltf, pyprimitive.material, pyprimitive, obj, vertex_color)
 
     def assign_material(gltf, pyprimitive, obj, bm, offset, cpt_index_mat):
         """Assign material to faces of primitives."""
         if pyprimitive.material is not None:
-            obj.data.materials.append(bpy.data.materials[gltf.data.materials[pyprimitive.material].blender_material])
+
+            vertex_color = None
+            if 'COLOR_0' in pyprimitive.attributes.keys():
+                vertex_color = 'COLOR_0'
+
+            obj.data.materials.append(bpy.data.materials[gltf.data.materials[pyprimitive.material].blender_material[vertex_color]])
             for vert in bm.verts:
                 if vert.index in range(offset, offset + pyprimitive.vertices_length):
                     for loop in vert.link_loops: