Make UiNode render pass respect render layers.

[jdm]

Objective

Ensures that UiNodes are only rendered to views with matching render layer configurations. Fixes #6069.

Solution

When UiNodes are queued, they are queued indiscriminately for each extracted view that exists. Since render layers can be a component of both the camera as well as the UiNode, we need to propagate the layer information in two ways:

• by adding render layer components to those extracted view entities so they can be queried later
• by adding render layer data to the UiBatches, so a batch of nodes all reference the same layer data

With this data propagated, we can perform a layer intersection check when queueing UiNodes against a particular view.

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Changelog

Fixed

UI components only render in views with matching render layers.

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[jdm]

These changes support both scenarios:

• UI components with no render layer, camera with explicit render layer
• UI components with render layer, camera with explicit render layer

[james7132]

This moves the render layer checks into the render app. Would it be possible to just check RenderLayers during extraction and just not extract the nodes that aren't visible?

[jdm]

This moves the render layer checks into the render app. Would it be possible to just check RenderLayers during extraction and just not extract the nodes that aren't visible?

I like this idea but I don't see how to do it. Does extraction run per-view? Right now there's no interaction with the view at all; how would I determine which one is the correct one to compare against?

[nicopap]

Have you seen #5414? This seems fairly similar. I closed it because UI nodes in the same layout would lead to very confusing results. This seem to exhibit the same behaviors.

Honestly, I don't think the confusion with different RenderLayers in same layout is a reason to block this PR, but it might be worth considering it since it was a motivation in closing previous attempts at this.

[jdm]

I have not seen that before. I will take some time to review the changes and discussion in that PR.

[1z-z1]

As someone who looking to pass different UI components and information to different viewports, this feature would be helpful.

[ickshonpe]

Having to set the render layers for each ui node individually doesn't seem good.

Maybe render layers could be added to UiStack instead of querying for the RenderLayers component in the extraction functions. Then when ui_stack_system walks the node tree if it finds a node with a RenderLayers component it could set all the descendants to those render layers as well.

[jdm]

Having read through #5414, I find the argument compelling that the interaction of layout with UI spread across multiple render layers is confusing. I agree that a more satisfying solution would be supporting multiple UI roots that could exist on separate layers instead (#5622).

[alice-i-cecile]

Having read through #5414, I find the argument compelling that the interaction of layout with UI spread across multiple render layers is confusing. I agree that a more satisfying solution would be supporting multiple UI roots that could exist on separate layers instead (#5622).

Given this, I'm going to close out this PR. We need a fix for this sort of thing eventually, but I don't think this is it.