Extensionsused - no longer populated with user extesions - help requested

[ronh991]

Describe the bug
The extensions used is no longer being populated with my user extensions. this was working as expected April 24. Is there a requirement for use extensions to be added to the extensionsused dsection. The extensions are part of all the other sections as needed. Just the extensions used is not

To Reproduce
Steps to reproduce the behavior:
Make and hook to add in a functionality for a user extension.

Expected behavior
userextension section is populated

Screenshots
pre April 24

	"extensionsUsed":[
		"ASOBO_normal_map_convention",
		"ASOBO_unique_id",
		"KHR_materials_specular",
		"KHR_materials_ior",
		"ASOBO_material_detail_map",
		"ASOBO_material_windshield",
		"ASOBO_material_shadow_options",
		"ASOBO_material_fresnel_fade",
		"ASOBO_material_glass",
		"ASOBO_material_blend_gbuffer"
	],

latest export

	"extensionsUsed":[
		"KHR_materials_clearcoat",
		"KHR_materials_specular",
		"KHR_materials_ior"
	],

.blend file/ .gltf (mandatory)
not available as you do not have the code that adds the extensions - Help request only

Version

• OS: win10

• Blender Version Blender 4.2 aebf

   "generator":"Khronos glTF Blender I/O v4.2.40 and Asobo Studio MSFS Blender I/O v2.2.3",
   "version":"2.0"
  

Additional context
Add any other context about the problem here.

[ronh991]

I have tracked this to the new extensions - rather than legacy add-ons. it is no longer registering my panel that triggers the user extensions to be added to the addon

[ronh991]

It seems there was a removal of the GLTF_PT_export_user_extensions panel class

[julienduroure]

Ah, yes, confirmed.

[julienduroure]

There is no more panel Classes for UI, Blender changed that, and it seems we forgot to update / find a solution for user extension.
Investigation in progress

[julienduroure]

Hello,
Blender changes will need you to update all your user extension addon UI.
You can see example addon to know how to update:

• There is no more Panel class declaration / register
• Instead, you need to create a "draw" function that let you create some layout panels on the fly
  See https://github.com/KhronosGroup/glTF-Blender-IO/tree/main/example-addons/example_gltf_exporter_extension

Your addon will also need a manifest file to be able to be installed.

[ronh991]

thanks, appreciate the quick response to this issue. Will work on the fix. I have the addon working with the toml manifest file already, just needed your update.

[eoineoineoin]

Have noticed a few problems with the draw() method in user extensions:

The header.props(props, 'enabled') adds a bunch of whitespace which looks bad and makes the labels hard to read

If the panel is collapsed, the line:

header, body = layout.panel("GLTF_addon_example_importer", default_closed=False)

Will return body=None, which breaks the example plugins. The following is printed to the console:

AttributeError: 'NoneType' object has no attribute 'active'
Traceback (most recent call last):
  File "/usr/share/blender/4.2/scripts/addons_core/io_scene_gltf2/__init__.py", line 1318, in draw
    export_panel_user_extension(context, layout)
  File "/usr/share/blender/4.2/scripts/addons_core/io_scene_gltf2/__init__.py", line 1715, in export_panel_user_extension
    draw(context, layout)
  File "/home/eoin/.config/blender/4.2/scripts/addons/example_gltf_exporter_extension/__init__.py", line 54, in draw
    body.active = props.enabled
    ^^^^^^^^^^^

Probably, the draw() needs to read:

def draw(context, layout):
    header, body = layout.panel("GLTF_addon_example_exporter", default_closed=False)

    props = bpy.context.scene.ExampleExtensionProperties

    header.prop(props, 'enabled')
    if body != None:
        body.prop(props, 'float_property', text="Some float value")

Finally, the method for extracting the draw() method is not great; if an addon provides a gltf2ImportUserExtension, the modules' draw() is registered in importer_extension_layout_draw:

glTF-Blender-IO/addons/io_scene_gltf2/__init__.py

Line 1837 in 93db353

if hasattr(sys.modules[addon_name], 'glTF2ImportUserExtension') or hasattr(sys.modules[addon_name], 'glTF2ImportUserExtensions'):

Similarly, if a module provides a gltf2ExportUserExtension, the same draw() function is registered in exporter_extension_layout_draw:

glTF-Blender-IO/addons/io_scene_gltf2/__init__.py

Line 1010 in 93db353

if hasattr(sys.modules[addon_name], 'glTF2ExportUserExtension') or hasattr(sys.modules[addon_name], 'glTF2ExportUserExtensions'):

)

However, if an addon provides both an importer and an exporter, then there's no way to determine what you should be drawing, so both the import and export options will show up in both the import and export windows.

[marwie]

We have the same issue regarding the UI showing up in import AND export. Having a way to determine which window is open would help a lot

[julienduroure]

Hello,
Thanks.
Right, we have to fix that!
I will have a look soon

[julienduroure]

Hello,

I propose to split the "draw" method into "draw_import" and "draw_export".
A fallback is kept for "draw", that will be displayed for both.
Please check #2313
I plan to merge it soon

[julienduroure]

Any feedback before I merge it?
@marwie @eoineoineoin @ronh991

[marwie]

I was just thinking if the info should be inside a third parameter instead of extra functions (some context object) but I'm not sure if this would have any benefit. draw_import and export is very explicit which is good!

[eoineoineoin]

Looks good to me, thanks!