This patch introduces a new Derived Resources concept to the compositor.
Derived resources are resources that are computed from a particular
result and cached in it in case it is needed by another operation, which
can greatly improve performance in some cases at the cost of more memory
usage.
The first use case is to store denoised versions of the Denoising Albedo
and Denoising Normals passes if auxiliary pass denoising is enabled in
the denoise node. Consequently, multi-pass denoising setups where the
same auxiliary passes are used in multiple denoise nodes should be much
faster due to caching of the derived resources.
This implementation has the limitation that it can't preemptively
invalidate the cache when the derived resources are no longer needed to
free up memory. This requires a special resource tracking mechanism that
need to happen during node tree compilation, and will be submitted
later. The limitation is not significant in the particular derived
resources that is currently implemented. Since the auxiliary passes are
rarely used outside of denoising.
Fixes#131171.
Pull Request: https://projects.blender.org/blender/blender/pulls/125671
2028bc8d7d