Since UVs are now stored as 2D vectors in meshes, they can be copied
directly to the vertex buffers. Somewhat surprisingly, multithreading
the copying into the vertex buffer provides a good speedup on a CPU
with many cores at least.
Here is a test uploading two UV maps created in geometry
nodes with a 1 million quad mesh, with a Ryzen 7950x:
| | Before | After | Speedup |
| Average | 24.3 ms | 7.5 ms | 3.2x |
| Min | 17.6 ms | 7.0 ms | 2.5x |
I added the copying utilities to the array utils header, since the
need for them has come up in a few different places already, and the
existing function with a selection argument didn't make sense here.
Hans Goudey