Bad glass refraction

[gagui]

This seems to happend only in beveled glass edges, like this:


How can i fix this?

Note: i put 10 levels in max depth in the refract map, but this doesn't seem to be the problem.

[samuel_bubat]

i´m not shure in this case, but in realworld glass refractions/reflections can look similar to the effect shown in your pic.

[natty]

looks like a reflection to me ...

[Da_elf]

looks like a smoothing group error

[gagui]

Those white oblique bands looks real for you?

Not for me.

I will check the smoothing groups Da_elf. Thanks.

[gagui]

The problem is more obious here:



One glass has bevel edges and the other one has not.

Im using EGZ Glass material.

I think the problem isn't the smoothing group Da_Elf.

[natty]

are you getting any warnings at all ?
like transparentcy levels ?

[gagui]

No warnings appear in my log window natty.

But i found the solution to this using a chanfer cylinder instead a cylinder converted to poly object and edge beveled.

In any case, it seems to be a problem with beveled glasses.

[samuel_bubat]

What you see there is a correct physical behaviour !
The stripes are just internal reflected chamfer faces.
When you take a closer look at some realworld glass table
you will see similar "stripes". Not that obvious but they are there.
You can verify this by by changing your refraction depth. As higher
the depth as more stripes will be visible.

Unfortunatelly Vray always reflects the inside, too.
No matter if you turn off "double-sided" or you deactivate
"reflect on backside" (Still working on 1.09)
When rendering with the scanliner (raytrace mat)
for example, you have to activate "double sided" to get the same effect.

I would darken the fog color a little bit, to make the edges darker
This will lower the effect and can make the glass more realistic.
You could also play with the angle of the chamfered faces.

Take a look at this quick test, wich shows the effect

1. Vray stripes
2. Scanline "double sided" stripes
3. Vray no fog
4. Vray fog









Hope this will help you a little

cheers

[trixian]

Wouldn't it just be better to build the glass with better geometry, as in more physically correct? Threre are no such things as smoothing groups in real life.
Infact....most likely, the only place you can find edges with similar characteristics are on cut gemstones like diamonds and such. For a fast fix one could try chamfering ones chamfered edges a few times with minute values...and then tesselate the rest so one could use one smoothing group instead.