Deleting loaded image results in failing export with `Image doesnt have any image data` error

[marwie]

Describe the bug Export fails if a material references a deleted image

To Reproduce Steps to reproduce the behavior:

1. Add image texture loaded from disc to material
2. Export glTF
3. All works fine, no errors
4. delete image from disc
5. observe error

Expected behavior Successful export without the referenced image - just a warning/error log that an image texture is missing

.blend file/ .gltf test.zip

Version

• OS: win 10
• Blender Version 3.6.2

Additional context

Traceback (most recent call last):
  File "c:\Program Files\Blender Foundation\Blender 3.6\3.6\scripts\addons\io_scene_gltf2\__init__.py", line 852, in execute
    return gltf2_blender_export.save(context, export_settings)
  File "c:\Program Files\Blender Foundation\Blender 3.6\3.6\scripts\addons\io_scene_gltf2\blender\exp\gltf2_blender_export.py", line 34, in save
    json, buffer = __export(export_settings)
  File "c:\Program Files\Blender Foundation\Blender 3.6\3.6\scripts\addons\io_scene_gltf2\blender\exp\gltf2_blender_export.py", line 51, in __export
    __gather_gltf(exporter, export_settings)
  File "c:\Program Files\Blender Foundation\Blender 3.6\3.6\scripts\addons\io_scene_gltf2\blender\exp\gltf2_blender_export.py", line 65, in __gather_gltf
    active_scene_idx, scenes, animations = gltf2_blender_gather.gather_gltf2(export_settings)
  File "c:\Program Files\Blender Foundation\Blender 3.6\3.6\scripts\addons\io_scene_gltf2\blender\exp\gltf2_blender_gather.py", line 28, in gather_gltf2
    scenes.append(__gather_scene(blender_scene, export_settings))
  File "c:\Program Files\Blender Foundation\Blender 3.6\3.6\scripts\addons\io_scene_gltf2\blender\exp\gltf2_blender_gather_cache.py", line 35, in wrapper_cached       
    result = func(*args, **kwargs)
  File "c:\Program Files\Blender Foundation\Blender 3.6\3.6\scripts\addons\io_scene_gltf2\blender\exp\gltf2_blender_gather.py", line 69, in __gather_scene
    node = gltf2_blender_gather_nodes.gather_node(
  File "c:\Program Files\Blender Foundation\Blender 3.6\3.6\scripts\addons\io_scene_gltf2\blender\exp\gltf2_blender_gather_nodes.py", line 34, in gather_node
    mesh=__gather_mesh(vnode, blender_object, export_settings),
  File "c:\Program Files\Blender Foundation\Blender 3.6\3.6\scripts\addons\io_scene_gltf2\blender\exp\gltf2_blender_gather_nodes.py", line 242, in __gather_mesh       
    result = gltf2_blender_gather_mesh.gather_mesh(blender_mesh,
  File "c:\Program Files\Blender Foundation\Blender 3.6\3.6\scripts\addons\io_scene_gltf2\blender\exp\gltf2_blender_gather_cache.py", line 35, in wrapper_cached       
    result = func(*args, **kwargs)
  File "c:\Program Files\Blender Foundation\Blender 3.6\3.6\scripts\addons\io_scene_gltf2\blender\exp\gltf2_blender_gather_mesh.py", line 57, in gather_mesh
    primitives=__gather_primitives(blender_mesh, uuid_for_skined_data, vertex_groups, modifiers, materials, export_settings),
  File "c:\Program Files\Blender Foundation\Blender 3.6\3.6\scripts\addons\io_scene_gltf2\blender\exp\gltf2_blender_gather_mesh.py", line 134, in __gather_primitives  
    return gltf2_blender_gather_primitives.gather_primitives(blender_mesh,
  File "c:\Program Files\Blender Foundation\Blender 3.6\3.6\scripts\addons\io_scene_gltf2\blender\exp\gltf2_blender_gather_cache.py", line 35, in wrapper_cached       
    result = func(*args, **kwargs)
  File "c:\Program Files\Blender Foundation\Blender 3.6\3.6\scripts\addons\io_scene_gltf2\blender\exp\gltf2_blender_gather_primitives.py", line 77, in gather_primitives
    material = gltf2_blender_gather_materials.gather_material(
  File "c:\Program Files\Blender Foundation\Blender 3.6\3.6\scripts\addons\io_scene_gltf2\blender\exp\gltf2_blender_gather_cache.py", line 35, in wrapper_cached       
    result = func(*args, **kwargs)
  File "c:\Program Files\Blender Foundation\Blender 3.6\3.6\scripts\addons\io_scene_gltf2\blender\exp\material\gltf2_blender_gather_materials.py", line 61, in gather_material
    pbr_metallic_roughness, uvmap_actives_pbr_metallic_roughness = __gather_pbr_metallic_roughness(blender_material, orm_texture, export_settings)
  File "c:\Program Files\Blender Foundation\Blender 3.6\3.6\scripts\addons\io_scene_gltf2\blender\exp\material\gltf2_blender_gather_materials.py", line 350, in __gather_pbr_metallic_roughness
    return gltf2_blender_gather_materials_pbr_metallic_roughness.gather_material_pbr_metallic_roughness(
  File "c:\Program Files\Blender Foundation\Blender 3.6\3.6\scripts\addons\io_scene_gltf2\blender\exp\gltf2_blender_gather_cache.py", line 35, in wrapper_cached       
    result = func(*args, **kwargs)
  File "c:\Program Files\Blender Foundation\Blender 3.6\3.6\scripts\addons\io_scene_gltf2\blender\exp\material\gltf2_blender_gather_materials_pbr_metallic_roughness.py", line 18, in gather_material_pbr_metallic_roughness
    base_color_texture, use_active_uvmap_base_color_texture, _ = __gather_base_color_texture(blender_material, export_settings)
  File "c:\Program Files\Blender Foundation\Blender 3.6\3.6\scripts\addons\io_scene_gltf2\blender\exp\material\gltf2_blender_gather_materials_pbr_metallic_roughness.py", line 100, in __gather_base_color_texture
    return gltf2_blender_gather_texture_info.gather_texture_info(inputs[0], inputs, export_settings)
  File "c:\Program Files\Blender Foundation\Blender 3.6\3.6\scripts\addons\io_scene_gltf2\blender\exp\material\gltf2_blender_gather_texture_info.py", line 22, in gather_texture_info
    return __gather_texture_info_helper(primary_socket, blender_shader_sockets, 'DEFAULT', filter_type, export_settings)
  File "c:\Program Files\Blender Foundation\Blender 3.6\3.6\scripts\addons\io_scene_gltf2\blender\exp\gltf2_blender_gather_cache.py", line 35, in wrapper_cached       
    result = func(*args, **kwargs)
  File "c:\Program Files\Blender Foundation\Blender 3.6\3.6\scripts\addons\io_scene_gltf2\blender\exp\material\gltf2_blender_gather_texture_info.py", line 43, in __gather_texture_info_helper
    index, factor = __gather_index(blender_shader_sockets, export_settings)
  File "c:\Program Files\Blender Foundation\Blender 3.6\3.6\scripts\addons\io_scene_gltf2\blender\exp\material\gltf2_blender_gather_texture_info.py", line 140, in __gather_index
    return gltf2_blender_gather_texture.gather_texture(blender_shader_sockets, export_settings)
  File "c:\Program Files\Blender Foundation\Blender 3.6\3.6\scripts\addons\io_scene_gltf2\blender\exp\gltf2_blender_gather_cache.py", line 35, in wrapper_cached       
    result = func(*args, **kwargs)
  File "c:\Program Files\Blender Foundation\Blender 3.6\3.6\scripts\addons\io_scene_gltf2\blender\exp\material\gltf2_blender_gather_texture.py", line 29, in gather_texture
    source, factor = __gather_source(blender_shader_sockets, export_settings)
  File "c:\Program Files\Blender Foundation\Blender 3.6\3.6\scripts\addons\io_scene_gltf2\blender\exp\material\gltf2_blender_gather_texture.py", line 81, in __gather_source
    return gltf2_blender_gather_image.gather_image(blender_shader_sockets, export_settings)
  File "c:\Program Files\Blender Foundation\Blender 3.6\3.6\scripts\addons\io_scene_gltf2\blender\exp\gltf2_blender_gather_cache.py", line 35, in wrapper_cached       
    result = func(*args, **kwargs)
  File "c:\Program Files\Blender Foundation\Blender 3.6\3.6\scripts\addons\io_scene_gltf2\blender\exp\material\gltf2_blender_gather_image.py", line 44, in gather_image    buffer_view, factor_buffer_view = __gather_buffer_view(image_data, mime_type, name, export_settings)
  File "c:\Program Files\Blender Foundation\Blender 3.6\3.6\scripts\addons\io_scene_gltf2\blender\exp\gltf2_blender_gather_cache.py", line 35, in wrapper_cached       
    result = func(*args, **kwargs)
  File "c:\Program Files\Blender Foundation\Blender 3.6\3.6\scripts\addons\io_scene_gltf2\blender\exp\material\gltf2_blender_gather_image.py", line 98, in __gather_buffer_view
    data, factor = image_data.encode(mime_type, export_settings)
  File "c:\Program Files\Blender Foundation\Blender 3.6\3.6\scripts\addons\io_scene_gltf2\blender\exp\material\extensions\gltf2_blender_image.py", line 136, in encode 
    return self.__encode_happy(export_settings), None
  File "c:\Program Files\Blender Foundation\Blender 3.6\3.6\scripts\addons\io_scene_gltf2\blender\exp\material\extensions\gltf2_blender_image.py", line 146, in __encode_happy
    return self.__encode_from_image(self.blender_image(), export_settings)
  File "c:\Program Files\Blender Foundation\Blender 3.6\3.6\scripts\addons\io_scene_gltf2\blender\exp\material\extensions\gltf2_blender_image.py", line 228, in __encode_from_image
    make_temp_image_copy(guard, src_image=image)
  File "c:\Program Files\Blender Foundation\Blender 3.6\3.6\scripts\addons\io_scene_gltf2\blender\exp\material\extensions\gltf2_blender_image.py", line 268, in make_temp_image_copy
    tmp_image.update()
RuntimeError: Error: Image '279895225900.png.001' does not have any image data