IPR GI settings

[Jiri.Matys]

Hi,

I think this could be important improvement of IPR.

Everyone have set up GI for some needs, primary for some good preview or final render. But IPR need fast GI, so both BF or secondary LC with low subdivs. And its terrible to loading presets or changing GI settings. I think IPR should have its own GI settings (only type of primary/secondary and subdivs) or just set some settings for fast preview by Chaos.

What do you think?

[vlado]

I'm not opposed to it, but I want to think a bit more carefully about this. The IPR already lowers some settings by the way (light cache subdivs and min. shading rate), we also have some ideas on how to generally speed up GI, so it will get better.

Best regards,
Vlado

[kosso_olli]

Is switching to BF/BF for IPR a good idea? I am thinking it might speed up the initial feedback, but will take longer to clear the noise.

[Pixelcon]

For me I use progressive, with BF+LC (yet to try BF+BF) and then switch to Bucket w/ IR+LC so for me this would be a good idea

[vlado]

Is switching to BF/BF for IPR a good idea?

I'm not sure. The light cache gives a pretty good idea of the image as a preview, and the IPR render is a lot closer to the production one. With V-Ray GPU, people always complain that the ActiveShade preview is darker than the final render because of the limited BF+BF bounces. I didn't want to make the same mistake again.

Best regards,
Vlado

[kosso_olli]

I'm not sure. The light cache gives a pretty good idea of the image as a preview, and the IPR render is a lot closer to the production one. With V-Ray GPU, people always complain that the ActiveShade preview is darker than the final render because of the limited BF+BF bounces. I didn't want to make the same mistake again.

Best regards,
Vlado

I see. Will stick with BF/LC then.

[Jiri.Matys]

I use BF/LC too. But when I set LC to 2000 for final render and then go IPR, its useless and have to stop it and change LC subdivs to 300 or something low to make IPR really realtime. You know what I mean.

[Alex_M]

For product shots, exteriors and very simple interiors I generally use BF+BF. For more complex interiors I use BF+LC 50-300 subdivs. For final renders I use BF+LC 1000-2000 subdivs. So for me it's not that big of a deal to change the GI settings between IPR and final renders.

[LudvikKoutny]

I recently found out V-Ray is a lot slower in some scenes with BF+BF due to the absence of Light Cache handling glossy reflections. Glossy reflections render significantly slower with BF+BF, so I try to utilize BF+LC as much as possible. Also, V-Ray seems to rely on LC more and more, with new adaptive lights for example. While I would love V-Ray to have reliable and reasonably fast BF only solution, at the moment it's not the case unfortunately.

[vlado]

As a side note, technically adaptive lights can be made to work with bf+bf if the progressive sampler is used, like we do in the GPU renderer. But then the bucket and progressive samplers would not be on par, and I didn't think it would be a good idea for the moment. We might do that in the future though.

Best regards,
Vlado

[LudvikKoutny]

As a side note, technically adaptive lights can be made to work with bf+bf if the progressive sampler is used, like we do in the GPU renderer. But then the bucket and progressive samplers would not be on par, and I didn't think it would be a good idea for the moment. We might do that in the future though.

Best regards,
Vlado

Yep, I guess consistency is more important here. Although I would like to see bucket sampler eventually deprecated, once progressive is able to handle PhoenixFD/Volumetrics better.

[Jiri.Matys]

Yes, agree with that.

And one more thing about IPR: if render is set to bucket, IPR render in bucket mode. I think IPR should automaticly change mode to progressive to be really IPR.

[vlado]

And one more thing about IPR: if render is set to bucket, IPR render in bucket mode. I think IPR should automaticly change mode to progressive to be really IPR.

Yes, I thought about this; I guess we will change it eventually.

Best regards,
Vlado