There are few issues with the logic and implementation of this option:
- While the first pass is faster in the terms of a wall-clock time, it
is often not giving usable results to artists, as the final look of
the result is so much different from what it is expected to be.
- It is not supported by the GPU compositor.
- It is based on some static rules based on the node type, rather than
on the apparent computational complexity.
The performance settings are planned to be moved to the RenderData, and
it is unideal to carry on such limited functionality to more places. There
are better approaches to quickly provide approximated results, which we can
look into later.
Pull Request: https://projects.blender.org/blender/blender/pulls/121558
6db8091f45