Blender 2.91 has support for the Intel OpenImageDenoise library. This is not available in Gentoo yet. An ebuild for Intel OpenImageDenoise would need to be added to Gentoo first, and then this can be added as an optional dependency to Blender, behind an USE flag. Reproducible: Always
Well, same deal for media-libs/oidn, CC'ing here as well in case.
This is almost the same as in bug #770103. Adrian and I have the same oidn version, but I haven't tried to build blender against it lately. I'm too busy with some of the bigger packages I have contributed to lately (freecad, vtk-9, opencascade update).
Yes, I filed both of these bugs. I made them separate, so that we don't overload one bug tracker page with too many unrelated things. I thought it would be useful to be able to track and discuss each of the missing optional dependencies independently.
I am testing oidn with blender in my blender-2.91.0 ebuild in my repository. However I will probably work on embree and draco first.
Fixed already in https://github.com/gentoo/gentoo/pull/20565. See the work in: bug 795003 bug 778008 bug 774372 bug 673422 bug 737388