Glass and Brute Force

[squeakybadger]

Hi,

We are using BF/LC as a renderer these days, but sometimes we have glass objects that aren't rendering correctly with the default settings.

Attached are 2 images, one being the defaults (no depth override), and one using depth override set at 30.

Can we get the glass to render correctly as the 30 subdiv example without having to set the depth over everything to 30, as that seems a bit overkill?

Thanks for any pointers.

[BBB3]

Even at 30, the bottom of the glass where it touches the table looks unnaturally dark, doesn't it?

[Alex_M]

You can manually set the reflection and refraction depths only for the glass material to something like 20-30. Did you try this and doesn't that work for you?

[piotrus3333]

looks like bottom of the glass cylinders is cooplanar with the white surface. it would also help to see your glass shader.

[squeakybadger]

Glass settings attached.

I've tried setting it to 30 in the reflect/refract depth of the material but it doesn't make a difference and renders dark.

The glass is a solid object with no flipped faces, and it is sitting about 1mm from the white top.

Even upping the global depth to 60 doesn't change how it is rendering on the bottom of the glass.

[Vizioen]

The darkness of the bottom is the reflection of the refraction of that copper thingy. Try rendering without them, shouldn't be that dark. Also, as stated, just up the reflection/refraction depth of your glass material not all of them by changing the override.

[squeakybadger]

The darkness of the bottom is the reflection of the refraction of that copper thingy. Try rendering without them, shouldn't be that dark. Also, as stated, just up the reflection/refraction depth of your glass material not all of them by changing the override.

Changing the depth on the glass material had no effect, all the glass was dark, not just the bottom.

[kosso_olli]

Also, the cutoff value is very high in the glass material. We often ran into problems with that, which is why in newer versions of V-Ray the default is now 0.001

[^Lele^]

Remake that shader, it's ancient as the cutoff value shows.
Fog units scaling is off too, and it's nearly an order of magnitude more reflective than it ought to be.
Also, why the diffuse component in a perfectly refractive object? It's going to be calculated for nothing at all (at facing angles refraction overrules it, at grazing angles reflection does.).
If you could anyways post the scene reduced to minimum terms (one plane and glass which show the issue, along with the lights and textures needed), one could be more precise as to why overriding global depth seems to fix the issue (besides total internal reflection and low shader bounces, coupled with the high cutoff. Too far a shot.).

[piotrus3333]

bottom of the cylinder should be sunk into the surface a bit.

[squeakybadger]

Just an update on this.

Rebuilt the shader from scratch, but didn't really change the look of anything.

Got it rendering correctly by changing the reflec/refrac values of anything that is picked up in the reflection/refraction of the glass to 30 (so the glass itself, the wall mat, the shelf mat and the copper mat)