Re: Test scences GPU Path vs CPU BiDir
Posted: Mon Aug 27, 2018 6:41 am
You are right. It is possible. Result depends on the size of the area light. Too large or too small does not work well.
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You are right. It is possible. Result depends on the size of the area light. Too large or too small does not work well.
I am not sure yet if glossy translucent depends on inner material. Texture applies at all surfaces, there is the option missing apply once and use transparent if uv map is out of mesh.wasd wrote: ↑Sun Aug 26, 2018 7:16 pmIt's not complex. It just isn't translucent. The only tricky part in it is how with rather thin volume and absolutely smooth surface it scatters light so evenly.
Here be the glossy translucent material transmitting 97% light on the left and glass on the right.
Both has heterogeneous volume with 0.001 scattering scale.
You have very peculiar translucent materials around you. I can hardly find one around me that will scatter light as much as glossy translucent does.FarbigeWelt wrote: ↑Mon Aug 27, 2018 10:22 pm This material behaves as one expects from a transluscent body.
As said, the cuboid in the picture is very thin and I miss scattering settings. You may need a model made from two 3D meshes for your purpose, one made from a very thin Glossy transluscent and the other made from Glass, both with clear volume and the same IOR. Heterogenous volume has a big influence on Glossy transluscent. In the picture above cuboid's depth is 1.0. In contrast to the earlier post, alpha channel is used for five faces and heterogenous volume as inner volume.wasd wrote: ↑Mon Aug 27, 2018 11:02 pmYou have very peculiar translucent materials around you. I can hardly find one around me that will scatter light as much as glossy translucent does.FarbigeWelt wrote: ↑Mon Aug 27, 2018 10:22 pm This material behaves as one expects from a transluscent body.
I can only do cpu rendering, and at least in that case, glossy translucent is not translucent at all. When it says it's 97% transmissive, that means that it in fact 3% reflective and absorbs everything else. Abandon all hope, photons who enter here! Glossy translucent mercilessly devours all photons brave enough to travel beyond surface, then with all it almighty surface violently emits violent photons of evil in every direction.
And that's the problem. Opacity is not physical property. And look at lasers, they are not bent. It is not glossy translucent you're testing, but opacity.
Good point. One cannot see the volume effect if one uses glossy translucent. Opacity 100% removes the surface completely, concluding there cannot be any refraction. Is there any refraction with glossy material expected? It is glossy not glassy.
You can see volume effect, but you can't see through, because of the name glossy translucent only first part is true.FarbigeWelt wrote: ↑Tue Aug 28, 2018 3:47 pm One cannot see the volume effect if one uses glossy translucent.
Of course refraction is expected with translucent material which IOR is different from its surrounding. Btw, glass is also glossy.FarbigeWelt wrote: ↑Tue Aug 28, 2018 3:47 pm Is there any refraction with glossy material expected? It is glossy not glassy.
Not sure what you mean by that.
You are right with this one. I was not precise enough.wasd wrote: ↑Tue Aug 28, 2018 4:53 pmYou can see volume effect,FarbigeWelt wrote: ↑Tue Aug 28, 2018 3:47 pm One cannot see the volume effect if one uses glossy translucent.
Volume effect: they are now both glossy translucent. Left is green, scattering scale 0.01, absorption depth 1 cm; right is red, scattering scale 10.0, absorption depth also 1 cm. Both has diffuse color #333333