Render point and spot light shadow maps only once, regardless of the number of cameras.#23713
Render point and spot light shadow maps only once, regardless of the number of cameras.#23713pcwalton wants to merge 4 commits intobevyengine:mainfrom
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number of cameras. The intention has long been to render shadow maps for point and spot lights only once, regardless of the number of views. This is reflected in the fact that `RetainedViewEntity::auxiliary_entity` is `Entity::PLACEHOLDER` for them. Unfortunately, this is currently inconsistently implemented, and a separate `ExtractedView` is presently spawned and rendered to for every point and spot light shadow map. The behavior of these views is inconsistent because they violate the invariant that there must only be one render-world view per `RetainedViewEntity`. This patch changes Bevy's behavior to spawn only one `ExtractedView` for point and spot lights. This required some significant rearchitecting of the render schedule because the render schedule is currently driven off cameras. Driving the rendering off cameras is incorrect for point and spot light shadow maps, which aren't associated with any camera. This PR fixes the regression on the `render_layers` test in `testbed_3d` in PR bevyengine#23481, in that it renders the way it rendered before that PR. Note, however, that the rendering isn't what may have been intended: the shadows don't match the visible objects. That's because the shadows come from point lights, which aren't associated with cameras, and therefore shadows are rendered using the default set of `RenderLayers`. A future patch may want to add flags to cameras that specify that they should have their own point light and spot light shadow maps that inherit the render layer (and HLOD) behavior of their associated cameras. As this patch is fairly large, though, and because my immediate goal is to fix the regression in bevyengine#23481, I think those flags are best implemented in a follow-up.
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Your PR caused a change in the graphical output of an example or rendering test. This might be intentional, but it could also mean that something broke! If it's expected, please add the M-Deliberate-Rendering-Change label. If this change seems unrelated to your PR, you can consider updating your PR to target the latest main branch, either by rebasing or merging main into it. |
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Your PR caused a change in the graphical output of an example or rendering test. This might be intentional, but it could also mean that something broke! If it's expected, please add the M-Deliberate-Rendering-Change label. If this change seems unrelated to your PR, you can consider updating your PR to target the latest main branch, either by rebasing or merging main into it. |
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Your PR caused a change in the graphical output of an example or rendering test. This might be intentional, but it could also mean that something broke! If it's expected, please add the M-Deliberate-Rendering-Change label. If this change seems unrelated to your PR, you can consider updating your PR to target the latest main branch, either by rebasing or merging main into it. |
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Your PR caused a change in the graphical output of an example or rendering test. This might be intentional, but it could also mean that something broke! If it's expected, please add the M-Deliberate-Rendering-Change label. If this change seems unrelated to your PR, you can consider updating your PR to target the latest main branch, either by rebasing or merging main into it. |
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The intention has long been to render shadow maps for point and spot lights only once, regardless of the number of views. This is reflected in the fact that
RetainedViewEntity::auxiliary_entityisEntity::PLACEHOLDERfor them. Unfortunately, this is currently inconsistently implemented, and a separateExtractedViewis presently spawned and rendered to for every point and spot light shadow map. The behavior of these views is inconsistent because they violate the invariant that there must only be one render-world view perRetainedViewEntity.This patch changes Bevy's behavior to spawn only one
ExtractedViewfor point and spot lights. This required some significant rearchitecting of the render schedule because the render schedule is currently driven off cameras. Driving the rendering off cameras is incorrect for point and spot light shadow maps, which aren't associated with any camera.This PR fixes the regression on the
render_layerstest intestbed_3din PR #23481, in that it renders the way it rendered before that PR. Note, however, that the rendering isn't what may have been intended: the shadows don't match the visible objects. That's because the shadows come from point lights, which aren't associated with cameras, and therefore shadows are rendered using the default set ofRenderLayers. A future patch may want to add flags to cameras that specify that they should have their own point light and spot light shadow maps that inherit the render layer (and HLOD) behavior of their associated cameras. As this patch is fairly large, though, and because my immediate goal is to fix the regression in #23481, I think those flags are best implemented in a follow-up.