Key render phases off the main world view entity, not the render world view entity. #16942
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view entity. We won't be able to retain render phases from frame to frame if the keys are unstable. It's not as simple as simply keying off the main world entity, however, because some main world entities extract to multiple render world entities. For example, directional lights extract to multiple shadow cascades, and point lights extract to one view per cubemap face. Therefore, we key off a new type, `RetainedViewEntity`, which contains the main entity plus a *subview ID*. This is part of the preparation for retained bins.
pcwalton
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Nothing gets drawn for the UI, but I'm not very familiar with the camera extraction internals and I couldn't quite unravel the problem.
Very loosely, from what I can tell:
extract_default_ui_camera_view spawns a default camera view entity for each camera which has an ExtractedView with subview_index: 1 and then creates a corresponding TransparentUi render phase.
But the extracted uinodes are given the entity id of the non-ui camera ExtractedView entity so that in queue_uinodes the non-ui view with subview_index: 0 is retrieved and then no TransparentUi phases are found because they were all keyed to subview_index: 1.
Setting the subview index to 1 in extract_cameras fixes the UI examples but that breaks everything else of course.
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This should fix the issue with the UI. The proper fix was a bit tricky and involved creating a new subgraph runner to make sure to run the UI rendering subgraph on the right render world entity. |
| let Some(mut render_views) = world.try_query::<&DefaultCameraView>() else { | ||
| return Ok(()); | ||
| }; | ||
| let Some(default_camera_view) = render_views.iter(world).next() else { |
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The multiple_windows example doesn't render the label for the second window. It seems that it just needs to look up the correct view using graph.view_entity() here:
| let Some(default_camera_view) = render_views.iter(world).next() else { | |
| let Ok(default_camera_view) = render_views.get(world, graph.view_entity()) else { |
We won't be able to retain render phases from frame to frame if the keys are unstable. It's not as simple as simply keying off the main world entity, however, because some main world entities extract to multiple render world entities. For example, directional lights extract to multiple shadow cascades, and point lights extract to one view per cubemap face. Therefore, we key off a new type,
RetainedViewEntity, which contains the main entity plus a subview ID.This is part of the preparation for retained bins.