* Shadow quality settings now specialization constant.
* Decal and light projector filters can be set.
* Changing those settings forces re-creation of the pipelines.
These changes should help improve performance related to shadow mapping, and allows improving performance by sacrificing decal and light projector quality.
* Keep track of when projector, softshadow or directional sofshadow were enabled.
* Enable them via specializaton constant where it makes sense.
* Re-implements soft shadows.
* Re-implements light projectors.
* Fixed and redone the process to obtain render information from a viewport
* Some stats, such as material changes are too difficult to guess on Vulkan, were removed.
* Separated visible and shadow stats, which causes confusion.
* Texture, buffer and general video memory can be queried now.
* Fixed the performance metrics too.
The Optimized shadow depth range was removed in late 2020 in favor
of the Stable shadow depth range, but it still had a (broken) property
that allowed to enable it.
* Removed entirely from RenderingServer.
* Replaced by ImmediateMesh resource.
* ImmediateMesh replaces ImmediateGeometry, but could use more optimization in the future.
* Sprite3D and AnimatedSprite3D work again, ported from Godot 3.x (though a lot of work was needed to adapt them to Godot 4).
* RootMotionView works again.
* Polygon3D editor works again.
* This is the 3D counterpart to #49632
* Implemented a bit different as 3D works using instancing
After merged, both 2D and 3D classes will most likely be renamed in a separate PR to DisplayNotifier2D/3D.
* GIProbe is now VoxelGI
* BakedLightmap is now LightmapGI
As godot adds more ways to provide GI (as an example, SDFGI in 4.0), the different techniques (which have different pros/cons) need to be properly named to avoid confusion.