This includes collision (2D SDF, Box, Sphere, Heightmap),
attraction (Box, Sphere), and all sorting modes.
This does not include 3D SDF collisions, trails, or
manual emission.
Due to the port to Vulkan and complete redesign of the rendering backend,
the `drivers/gles3` code is no longer usable in this state and is not
planned to be ported to the new architecture.
The GLES2 backend is kept (while still disabled and non-working) as it
will eventually be ported to serve as the low-end renderer for Godot 4.0.
Some GLES3 features might be selectively ported to the updated GLES2
backend if there's a need for them, and extensions we can use for that.
So long, OpenGL driver bugs!
As of clang-format 6.0.1, putting the `/* clang-format off */` hint
around our "invalid" `[vertex]` and `[shader]` statements isn't enough
to prevent a bogus indent of the next comments and first valid statement,
so we need to enclose that first valid statement in the unformatted chunk.
