SSS2 prepass and GI.

[jstrob]

Hi,

I just noticed that GI has no effect on a SSS2 material in pre-pass mode. Is that correct? It seems like GI is simulated in the prepass? That means we should always render a pass with SSS2 objects alone and deactivate GI for this pass.

[tashko.zashev]

In order to include the GI in the illumination map used to approximate the subsurface scattering, you have to enable Scatter Gi option in the SSS2 material parameters.

[vlado]

I just noticed that GI has no effect on a SSS2 material in pre-pass mode. Is that correct? It seems like GI is simulated in the prepass? That means we should always render a pass with SSS2 objects alone and deactivate GI for this pass.

Are you using irradiance map for GI? If yes, what is the min/max rate? Also, what is the prepass rate of the sss2 material?

Best regards,
Vlado

[jstrob]

I always use brute force and light cache for animation. Prespass rate is zero. scatter GI is enabled in SSS2. So in that case that means we can turn off GI in the render settings for a pass containing only the SSS2 objects?

[vlado]

This seems like a bug. I'm working on a fix now and I should be able to get it to you as soon as I have it.

Best regards,
Vlado

[vlado]

In the meantime you could try the object-space method, which works fine and it should give very similar results (you might have to adjust the "samples per unit area"). Or you could turn off "scatter GI" - should also work fine.

Best regards,
Vlado