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ZdenniZ avatar image
ZdenniZ asked FlyingRaccoon answered

Weird glass material behavior

TestCube.zipI am working with SU7 Beta. I know overlapping glass materials are not supported, but this issue is completely different. Somehow, only the front face of the glass polygon is transparent, whereas its back side is not transparent and is mirror-like:


You can see a simple cube with one face detached and moved away. The glass material is pplied to the detached face and to the opposite side of the cube. The polygon facing the camera on the cube is transparent but the back side of the detached face is not. Here's what's happening on the other side:


So now it's vice a versa.

Here are my material settings:

1641444770712.png 1641444821502.png

Another object in my scenery compiled with an earlier SDK version shows transparency both ways no problem. Any advice? Thanks.

UPDATE: It seems to work fine if I duplicate the face with the glass material applied, flip its normal and remove the double-sided checkmark. However this doubles the polygons, not sure this is what was intended. Previously the double-sided property worked just fine.

UPDATE 2: Seems I have figured this out. It is caused by Roughness factor set to 0 as previously advised here at devsupport. Roughness 0.5 gets everything back to normal. Did this change again in SU7?

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1 Answer

FlyingRaccoon avatar image
FlyingRaccoon answered

Hello @ZdenniZ

Using multiple overlapping glass layers is no longer an issue. This is part of the changes that came with SU7.

Your problem comes from using the double sided property. This should only be enabled when shading is not very important as the normals are not changed for backface. You want to duplicate faces and invert normals yourself to have a real and correct double sided material.

This was already a problem before but has become more visible with the new glass material.

@Nocturne FYI


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