Disable RmlUI document if scene is not visible

[gleblebedev]

No description provided.

[rokups]

IMO it would make more sense for component to follow scene->IsUpdateEnabled(). This knob specifically disables updates to scene and all of it's components, while UI alone can be disabled explicitly by calling component->SetEnabled(false).

[gleblebedev]

IMO it would make more sense for component to follow scene->IsUpdateEnabled(). This knob specifically disables updates to scene and all of it's components, while UI alone can be disabled explicitly by calling component->SetEnabled(false).

Will disabling updates stop UI from rendering? I don't think so.

Calling SetEnabled is not convenient. The problem is that switching between application states should switch visible rmlui elements. For classic UI I solve this by replacing a UI Root element in UI subsystem. There is no such thing in RmlUI subsystem.

There should be a better way of doing this but coming up with it may take a long time.

[rokups]

Will disabling updates stop UI from rendering? I don't think so.

It does not, but it could. E_SCENEUPDATECHANGED event could be added, which fires whenever Scene::SetUpdateEnabled() is called. Then component can subscribe to this event and show/hide UI.

Calling SetEnabled is not convenient.

This is an option for other usecases. Maybe we want invisible scene still doing UI, maybe we want visible scene not doing UI. Combination of E_SCENEUPDATECHANGED+SetEnabled allow both

[gleblebedev]

Ok, I'll update the PR tonight.

[eugeneko]

It does not, but it could

But should it?
We render scene that is not updated all the time in the Editor.
Why should we render Scene and not render UI?

[rokups]

That makes sense 🤔

[eugeneko]

@gleblebedev did you check that render to texture works as expected (e.g. in samples)?

[gleblebedev]

@gleblebedev did you check that render to texture works as expected (e.g. in samples)?

No :-( I forgot about it

[gleblebedev]

Is it also done with component? Why component?

[rokups]

Our workflow is component-centric, it was a natural fit for ui in the editor. But maybe component is implemented wrong. Maybe ui should be rendered as an overlay on the scene. In that case not rendering scene would not render ui automagically. Although input handling would start to depend on viewport rect. It would also play well with editor...