Add all avalaible materials in export

addons/io_scene_gltf2/blender/exp/gltf2_blender_export.py

@@ -61,7 +61,7 @@ def __export(export_settings):
 
 
 def __gather_gltf(exporter, export_settings):
-    active_scene_idx, scenes, animations = gltf2_blender_gather.gather_gltf2(export_settings)
+    active_scene_idx, scenes, animations, materials = gltf2_blender_gather.gather_gltf2(export_settings)
 
     plan = {'active_scene_idx': active_scene_idx, 'scenes': scenes, 'animations': animations}
     export_user_extensions('gather_gltf_hook', export_settings, plan)
@@ -75,7 +75,8 @@ def __gather_gltf(exporter, export_settings):
         exporter.add_scene(scene, idx==active_scene_idx)
     for animation in animations:
         exporter.add_animation(animation)
-
+    for material in materials:
+        exporter.add_material(material)
 
 def __create_buffer(exporter, export_settings):
     buffer = bytes()

addons/io_scene_gltf2/blender/exp/gltf2_blender_gather.py

@@ -18,6 +18,7 @@
 from io_scene_gltf2.io.com.gltf2_io_debug import print_console
 from io_scene_gltf2.blender.exp import gltf2_blender_gather_nodes
 from io_scene_gltf2.blender.exp import gltf2_blender_gather_animations
+from io_scene_gltf2.blender.exp import gltf2_blender_gather_materials
 from io_scene_gltf2.blender.exp.gltf2_blender_gather_cache import cached
 from ..com.gltf2_blender_extras import generate_extras
 from io_scene_gltf2.blender.exp import gltf2_blender_export_keys
@@ -32,14 +33,20 @@ def gather_gltf2(export_settings):
     """
     scenes = []
     animations = []  # unfortunately animations in gltf2 are just as 'root' as scenes.
+    materials = []
     active_scene = None
     for blender_scene in bpy.data.scenes:
         scenes.append(__gather_scene(blender_scene, export_settings))
         if export_settings[gltf2_blender_export_keys.ANIMATIONS]:
             animations += __gather_animations(blender_scene, export_settings)
         if bpy.context.scene.name == blender_scene.name:
             active_scene = len(scenes) -1
-    return active_scene, scenes, animations
+
+    for material in bpy.data.materials:
+        double_sided = not material.use_backface_culling
+        materials.append(gltf2_blender_gather_materials.gather_material(material, double_sided, export_settings))
+
+    return active_scene, scenes, animations, materials
 
 
 @cached

addons/io_scene_gltf2/blender/exp/gltf2_blender_gltf2_exporter.py

@@ -192,6 +192,18 @@ def add_animation(self, animation: gltf2_io.Animation):
 
         self.__traverse(animation)
 
+    def add_material(self, material: gltf2_io.Material):
+        """
+        Add an material to the glTF.
+
+        :param material: glTF material, with python style references (names)
+        :return: nothing
+        """
+        if self.__finalized:
+            raise RuntimeError("Tried to add material to finalized glTF file")
+
+        self.__traverse(material)
+
     def __to_reference(self, property):
         """
         Append a child of root property to its respective list and return a reference into said list.