VrayBlend with refractive materials

[gagui]

Hello.

I'm having some problems doing a simple animated change of materials.
I'm using Vray blend where I connect an animated vray color in the blend amount to control the transition between the two materials.
One of the materials is refractive and the VrayBlend seem to not hadle well this type of mix.

Any work around to make such a simple task?

[fixeighted]

Not sure I understand...but if it is what I see happening with the blend, with the 'glass' not rendering as expected, then swapping the shaders will make it work, so using the refractive one as the base.
If I'm mistaken then you'll have to be more specific

[gagui]

Yes, you're right. If I swap the materials works fine.
Now the next problem is when instead of blending a refractive material and a solid one I need to blend a refractive material and a sss material.
Is there any way to do this?

[fixeighted]

Only one way to find out

There is an issue still with this setup, as the refractive material refuses to show in the alpha....or rather it did, once, but I cannot make it work again, which is very odd and feels buggy.
I think it has to do with the gradient ramp not working right here...

[gagui]

You could try with a checker map instead and see if it works in any way

[fixeighted]

It occurs to me that no, a blend with SSS won't work, as it needs actual volume, where the blend will just see it as single sided.

[gagui]

Then the only way to make a nice transition between two refractive materials is through comp, isn't it?

[fixeighted]

Hmm...guess it could be done, depending on the complexity of the objects. Or if it's possible you could build each part separately, to allow more control.
What is the object?

[Vizioen]

What about duplicating the object and animating the visibility, and using secondary ray bias to prevent Z fighting. (Just thinking out loud, no idea if that would work or produce the results you want). Also if the camera is not animated isn't it way faster/easier in comp? (Or even if it's animated, just render the overlapping frames with the different materials).