* 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.
* Added support to our local copy of SpirV Reflect (which does not support it).
* Pass them on render or compute pipeline creation.
* Not implemented in our shaders yet.
* IF a texture was reimported (calling replace as an example), it would invalidate all materials using it, causing plenty of errors.
* Added the possibility to get a notification when a uniform set is erased.
* With this notification, materials can be queued for update properly.
* Implements the code to show the boot splash on load using RenderingDevice
* Does not work on X11 when maximized, some platform specific hack will be needed there.
* 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.
* Colors were imported as 16BPP (half float)
* Far most common use cases only require 8BPP
* If you need higher data precision, use a custom array, which are supported now.
**WARNING**: 3D Scenes imported in 4.0 no longer compatible with this new format. You need to re-import them (erase them from .godot/import)
* 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.
* Editor 2D viewport now uses embedded subwindows (windows no longer pop up)
* Restored the ability to disable 3D on the 2D viewport (makes 3D not display on 2D when there is a camera on the scene)
* Ability to allocate empty objects in RID_Owner, so RID_PtrOwner is not needed in most cases.
* Improves cache usage, as objects are now allocated together
* Should improve performance in 2D rendering
