VRayFastSSS2 "Scatter GI" interpolation / adaptive sampling

[insanetk]

VRayFastSSS2 is NOT fast with Scatter GI on. It seems to do the SSS pass with Scatter GI in brute force mode. It slows down even more based on how high the hemispheric subdivision in Irradiance map is. It seems to recaculating the entire GI environment after the initial GI pass, not using what was already calculated.

Why is it not able to do internal scattering approximation like the method you can use in VRayMtl with refraction + interpolation, even brute force in VRayMtl with raw glossiness in refraction with the SSS particles can be faster then VrayFastSSS2+scatter gi.

I don't see why there is no interpolation or adaptive sampling in the scatter gi function, makes no sense to me. :P

[vlado]

This is on the "to do" list.

Best regards,
Vlado

[insanetk]

That sounds great! I assume the new SSS2 shader build Blur Studio got from Chaosgroup is that "to do" SSS2 improvement. I'm wondering if this is gonna be in the first release of V-Ray 2.0. This improvement is a big deal for me in a character design project I'm doing at university.

[vlado]

The improvement for Blur was the addition of the "prepass id" parameter that allows several sss2 shaders to share the same illumination map. This feature is in SP5 already.

Best regards,
Vlado