IPR light cache

[Art48]

Hi,

I think in RT if you have set your GI to BF+LC you don't actually see the lightcache being created but instantly have your image visible on-screen. I noticed when using the new IPR you see the LC getting calculated every time you change something. This is obviously logical but from an artist point of view I would rather have it behave like RT where the LC calculation time doesn't distract me from the image I am working on, even at the expense of feedback time.

For the time being I could switch to BF+BF, but I'd prefer BF+LC.

[svetlozar.draganov]

Hi,

I think in RT if you have set your GI to BF+LC you don't actually see the lightcache being created but instantly have your image visible on-screen. I noticed when using the new IPR you see the LC getting calculated every time you change something. This is obviously logical but from an artist point of view I would rather have it behave like RT where the LC calculation time doesn't distract me from the image I am working on, even at the expense of feedback time.

For the time being I could switch to BF+BF, but I'd prefer BF+LC.

LC is not supported on RT for that reason actually to have an instant preview.
IPR rendering however should work with LC for sure and when LC is enabled it will be calculated with each IPR update so you have to decide whether you would like to have instant feedback with BF+BF or you would like to use LC at the price of its recalculation. Another option which might be helpful is to load LC from a file, that would give you instant update but the GI solution might not be very accurate.

[Art48]

Oh I thought I read some patch notes a while ago about LC being supported in RT now. Was that GPU then? Or am I confusing something here?
Anyways I see. I think I will roll with BF+BF then for the time being.

[svetlozar.draganov]

It is supported when RT is assigned as a Production Renderer where the recalculation of it is not an issue.
When ActiveShade is used it is not very handy to recalculate LC for each change that's why it is disabled.

LC should be calculated very fast when rendering with IPR is there any noticeable differences when using BF+BF and BF+LC?

[Art48]

There are no noticable differences besides BF+BF being slower taking more time to clean up noise. But in the IPR phase I am not after noise cleanup but after lighting and shader development. And especially in case of lighting it is just distracting to see the LC calculating. for VERY broad and general lighting setup it may be okay since you get an early preview but when it is in the stage of adjusting light intensities and nuanced positioning etc it just becomes distracting seein the LC calculate.

I would rather take a few seconds delay where my image is staying the same in the VFB while LC gets calculated, then gets replaced with the actual rendering image instead of GI preview.

Edit: The "Show calc phase" checkbox seems to have no effect in IPR, it is always visible.