Multiple transparent materials per object

[gingerskull]

Hi,

I have a problem assigning two transparent materials to the same object. When I do that, the refractions at the boundary between the two materials are wrong.
In the attached screenshot, I assigned the same simple glass material to the object and a bunch of faces separately. Any idea what causes this?

[linograndiotoy]

I've tried here and it works as expected.
Did you check the normals of your model?

[glasshandfilms]

This still does not work in the latest version : OctaneRender™ for Blender 2020.2.3 - 23.5 [STABLE]

I have a bottle that has a displacement shader on the outside, and another shader that has no displacement applied to the polygons on the inside.

[linograndiotoy]

Can you be more specific about what you're trying to achieve?
Again, assigning 2 different materials, transparent or not, works perfectly here.