viewport material export

addons/io_scene_gltf2/__init__.py

@@ -497,6 +497,9 @@ class ExportGLTF2_Base(ConvertGLTF2_Base):
             ('PLACEHOLDER',
              'Placeholder',
              'Do not export materials, but write multiple primitive groups per mesh, keeping material slot information'),
+            ('VIEWPORT',
+            'Viewport',
+            'Export minimal materials as defined in Viewport display properties'),
             ('NONE',
              'No export',
              'Do not export materials, and combine mesh primitive groups, losing material slot information')),

addons/io_scene_gltf2/blender/exp/material/material_utils.py

@@ -0,0 +1,23 @@
+# Copyright 2018-2024 The glTF-Blender-IO authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from ...com.extras import generate_extras
+
+def gather_extras(blender_material, export_settings):
+    if export_settings['gltf_extras']:
+        return generate_extras(blender_material)
+    return None
+
+def gather_name(blender_material, export_settings):
+    return blender_material.name

addons/io_scene_gltf2/blender/exp/material/material_viewport.py

@@ -0,0 +1,42 @@
+# Copyright 2018-2024 The glTF-Blender-IO authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from ....io.com import gltf2_io
+from .material_utils import gather_extras, gather_name
+
+def export_viewport_material(blender_material, export_settings):
+
+    pbr_metallic_roughness = gltf2_io.MaterialPBRMetallicRoughness(
+        base_color_factor=list(blender_material.diffuse_color),
+        base_color_texture=None,
+        metallic_factor=blender_material.metallic,
+        roughness_factor=blender_material.roughness,
+        metallic_roughness_texture=None,
+        extensions=None,
+        extras=None
+    )
+
+    return gltf2_io.Material(
+        alpha_cutoff=None,
+        alpha_mode=None,
+        double_sided=None,
+        emissive_factor=None,
+        emissive_texture=None,
+        extensions=None,
+        extras=gather_extras(blender_material, export_settings),
+        name=gather_name(blender_material, export_settings),
+        normal_texture=None,
+        occlusion_texture=None,
+        pbr_metallic_roughness=pbr_metallic_roughness
+    )

addons/io_scene_gltf2/blender/exp/material/materials.py

@@ -18,11 +18,12 @@
 from ....io.com import gltf2_io
 from ....io.com.gltf2_io_extensions import Extension
 from ....io.exp.user_extensions import export_user_extensions
-from ...com.extras import generate_extras
 from ..cache import cached, cached_by_key
 from . import unlit as gltf2_unlit
 from . import texture_info as gltf2_blender_gather_texture_info
 from . import pbr_metallic_roughness as gltf2_pbr_metallic_roughness
+from .material_utils import gather_extras, gather_name
+from .material_viewport import export_viewport_material
 from .extensions.volume import export_volume
 from .extensions.emission import export_emission_factor, \
     export_emission_texture, export_emission_strength_extension
@@ -69,6 +70,12 @@ def gather_material(blender_material, export_settings):
         return None, {"uv_info": {}, "vc_info": {'color': None, 'alpha': None,
                                                  'color_type': None, 'alpha_type': None, 'alpha_mode': "OPAQUE"}, "udim_info": {}}
 
+
+    if export_settings['gltf_materials'] == "VIEWPORT":
+        return export_viewport_material(blender_material, export_settings), {"uv_info": {}, "vc_info": {'color': None, 'alpha': None,
+                                                 'color_type': None, 'alpha_type': None, 'alpha_mode': "OPAQUE"}, "udim_info": {}}
+
+
     # Reset exported images / textures nodes
     export_settings['exported_texture_nodes'] = []
     if blender_material.node_tree and blender_material.use_nodes:
@@ -117,8 +124,8 @@ def gather_material(blender_material, export_settings):
         emissive_factor=emissive_factor,
         emissive_texture=emissive_texture,
         extensions=extensions,
-        extras=__gather_extras(blender_material, export_settings),
-        name=__gather_name(blender_material, export_settings),
+        extras=gather_extras(blender_material, export_settings),
+        name=gather_name(blender_material, export_settings),
         normal_texture=normal_texture,
         occlusion_texture=occlusion_texture,
         pbr_metallic_roughness=pbr_metallic_roughness
@@ -327,16 +334,6 @@ def __gather_extensions(blender_material, emissive_factor, export_settings):
     return extensions, uvmap_infos, udim_infos
 
 
-def __gather_extras(blender_material, export_settings):
-    if export_settings['gltf_extras']:
-        return generate_extras(blender_material)
-    return None
-
-
-def __gather_name(blender_material, export_settings):
-    return blender_material.name
-
-
 def __gather_normal_texture(blender_material, export_settings):
     normal = get_socket(blender_material.node_tree, blender_material.use_nodes, "Normal")
     normal_texture, uvmap_info, udim_info, _ = gltf2_blender_gather_texture_info.gather_material_normal_texture_info_class(
@@ -501,8 +498,8 @@ def __export_unlit(blender_material, export_settings):
         alpha_mode=__gather_alpha_mode(alpha_info, export_settings),
         double_sided=__gather_double_sided(blender_material, {}, export_settings),
         extensions={"KHR_materials_unlit": Extension("KHR_materials_unlit", {}, required=False)},
-        extras=__gather_extras(blender_material, export_settings),
-        name=__gather_name(blender_material, export_settings),
+        extras=gather_extras(blender_material, export_settings),
+        name=gather_name(blender_material, export_settings),
         emissive_factor=None,
         emissive_texture=None,
         normal_texture=None,
@@ -677,7 +674,7 @@ def __get_final_material_with_indices(blender_material, base_material, caching_i
 
 def get_material_from_idx(material_idx, materials, export_settings):
     mat = None
-    if export_settings['gltf_materials'] == "EXPORT" and material_idx is not None:
+    if export_settings['gltf_materials'] in ["EXPORT", "VIEWPORT"] and material_idx is not None:
         if materials:
             i = material_idx if material_idx < len(materials) else -1
             mat = materials[i]