Glass Edges Creating NOISE

[ntavian]

hey forum members
I am having trouble when I have a piece of glass that terminates against a wall, or when 2 pieces of glass form a corner, or one piece of glass ends against the other perpendicularly,
I am getting a very noisy edge

I think it has to do with the geometry touching each other

I have been playing with the "Secondary rays bias" using .005 like the vray help guide says but I cannot get a clean edge

(please excuse the poor rendered images)

thanks in advance

[Neilg]

move it apart 1mm or something.

[Jason Stewart]

Those faces are occupying the same space not touching. Separate them slightly and the problem will be gone.

[Vizioen]

Those faces are occupying the same space not touching. Separate them slightly and the problem will be gone.

While that might work to get rid of the noisey edge, i'm wondering. How do you get rid of these things for instance a glass pane in an exterior window with a aluminum frame. If u leave a tiny gap, you have light leaks. If you push it in the geometry you might not see the glass edge which has a different color. I always let it touch, I used to be able to live with the noise but as I start to strive towards realism, I don't see how to overcome things touching things. Actually in real life there's no such thing as two things touching eachother perfectly on molecular level, there's always a gap, but it's just microscopically small.

[rjohnson33]

If you're striving for realism then the edges of the pane(s) of glass would typically be recessed into the frame itself - so you could model that if you felt you were going to get close enough to see the detail.
Or whatever the real life interface is supposed to be - if you look up a reference section for the detail or a similar one you should be able to recreate it without 'cheating'.

[Macker]

Agreed with the above, if you want absolute realism then you ought to start modelling it as per the construction details. The glass would be sat within a frame, which itself would be recessed into the wall, or the plasterboard/tiles built out to sheath it.

A quick google search shows loads of suitable details.

[Vizioen]

Agreed with the above, if you want absolute realism then you ought to start modelling it as per the construction details. The glass would be sat within a frame, which itself would be recessed into the wall, or the plasterboard/tiles built out to sheath it.

A quick google search shows loads of suitable details.

Actually in Interiors I do that if I get close enough to the frame. I actually had the same problem when not modelling the entire frame. Come to think of it last time I modelled the entire frame I didn't seem to have the noise problem, which is weird because my glass was touching rubber sides and a metallic place holder. EDIT: actually the noise is probably there but u can't see it because of the black rubber.




And this was the result (on the left side; drag into new tab for full resolution)

[rjohnson33]

EDIT: actually the noise is probably there but u can't see it because of the black rubber.

Maybe, but why not drag those edges away from one another so you don't have to worry about coplanar faces at all? (I think there was a recent thread somewhere that suggested coplanar faces were increasing render times also)

I'd just zoom in close and shift them a tiny amount apart or build them slightly apart in the first instance (I'd rather work that way in 3dsMax anyway because the snapping is dreadful - But looks like you might be modelling in SketchUp so don't know if you have to work with your geometry perfectly aligned like that)

[Vizioen]

Maybe, but why not drag those edges away from one another so you don't have to worry about coplanar faces at all? (I think there was a recent thread somewhere that suggested coplanar faces were increasing render times also)

I'd just zoom in close and shift them a tiny amount apart or build them slightly apart in the first instance (I'd rather work that way in 3dsMax anyway because the snapping is dreadful - But looks like you might be modelling in SketchUp so don't know if you have to work with your geometry perfectly aligned like that)

Well, in that regard don't I have to worry about light leaking through those edges? Even if they are a tiny bit apart? Light leaks can also increase rendertime, or am I wrong.

And you're absolutely right about the dreadfull max snapping that's one of the reasons I model in SketchUp.

[rjohnson33]

Well, in that regard don't I have to worry about light leaking through those edges? Even if they are a tiny bit apart? Light leaks can also increase rendertime, or am I wrong.

And you're absolutely right about the dreadfull max snapping that's one of the reasons I model in SketchUp.

When I first started with Max I came from a background of working with AutoCAD as a draftsperson for Structural Engineers and just couldn't handle the idea of not being able to make quick and definite feeling snaps at first!
Took me a long while to loosen up to the concept that really visually aligning objects in the viewport was fine as far as visualisation worked out.

As far as light leaks are concerned I don't think there is any issue in terms of the final result - I mean you'd have to have quite a significant gap and a strong directional light source beyond to actually see any distinct light/shadow cast through that gap.

With the render time maybe someone with a better handle on the ray tracing could advise? I'd always assumed there would be some kind of accuracy cut-off level that means rays wouldn't bounce around in microscopic spaces. I could easily be wrong.

[svetlozar.draganov]

Light leaks can also increase rendertime, or am I wrong.

Yes - they will increase render times but in general the difference won't be so noticeable unless the light source intensity is with an extreme values.

[Shimakaze]

And you're absolutely right about the dreadfull max snapping that's one of the reasons I model in SketchUp.

I would ask them to try and fix it, but after they "fixed" viewport navigation in 2015 I don't know if I want them to even try to fix anything again ever.