Second try to fix missing previews of mat/tex/etc. in .blend files.

This time, it's a dedicated operator user has to run before saving the file.

And it recursively check all IDs linked from each scene, therefore rendering
materials etc. previews using a scene they are used in.

Note the renderengine issue is not completely addressed this way
(existing code for icon previews seems to ignore completely other engines,
and IDs not linked anywhere (fake-user ones) will be rendered with current scene's engine
as fallback, also you can get a material linked to an hidden object in a scene, etc.).

Reviewers: sergey, campbellbarton

Reviewed By: campbellbarton

Differential Revision: https://developer.blender.org/D980

1 files changed, 2 insertions, 1 deletions

diff --git a/source/blender/editors/include/UI_interface_icons.h b/source/blender/editors/include/UI_interface_icons.h
index 2ba3d309aa7..74927428363 100644
--- a/source/blender/editors/include/UI_interface_icons.h
+++ b/source/blender/editors/include/UI_interface_icons.h
@@ -64,7 +64,8 @@ void UI_icons_init(int first_dyn_id);
 int UI_icon_get_width(int icon_id);
 int UI_icon_get_height(int icon_id);
 
-void UI_id_icon_render(const struct bContext *C, struct ID *id, const bool big, const bool use_job);
+void UI_id_icon_render(
+        const struct bContext *C, struct Scene *scene, struct ID *id, const bool big, const bool use_job);
 
 void UI_icon_draw(float x, float y, int icon_id);
 void UI_icon_draw_preview(float x, float y, int icon_id);