VFB and switching on test resolution

[SonyBoy]

I'd really like to see the VFB have the ability to retain any previous rendered parts of an image even after turning on test resolution and re-rendering just a region. Currently when following this workflow, any areas outside of the region are purged. This is really detrimental to workflow in most cases, and there is a purge button (red X) in the UI to remove it if preferred.

[hermit.crab]

I'd really like to see the VFB have the ability to retain any previous rendered parts of an image even after turning on test resolution and re-rendering just a region. Currently when following this workflow, any areas outside of the region are purged. This is really detrimental to workflow in most cases, and there is a purge button (red X) in the UI to remove it if preferred.

I'm unsure how that will work when rendering two regions with different resolutions. If it did retain the last rendered region, the new region will have to adapt to the already chosen resolution, be it the test one or the regular one, which may not be desirable.

[SonyBoy]

I should clarify that I'm not talking about using such renders for any kind of output, and obviously the two renders would not share the same resolution, but I would have thought it would be possible to scale the previous render up or down to match the newly set test resolution and retain those pixels. During lookdev it's often desirable to use regions to fine tune certain areas, but having the entire image in the VFB is usually very helpful for context.