Rendering of a glass of wine (materials and geometry)

[3dben]

Hello Everybody,

I'm asking help for a scene that looks simple :
achieve a realistic rendering of a glass with wine.
The fact is, that generaly, people let a gap between the wine geometry and the glass geometry.
But, if the ior of the glass is bigger than the wine ior, then you should see as the wine fill the glass border (you can see a photo beneath in the study).

Here are my differents tries :


03g version.

The Glass is set with ior=1.6.

My big questions are:
1) What is the correct geometry to set?
2) What is the correct material to set ?
3) What about the shadows? (affect shadows is also checkd for the glass, vray shadows used)
4) =>Vlado) How vray consider the ior when the wine (1.333) is inside the glass (1.6) (the third case).

Here is a render with the third case used (fog density=2) plus GI :

Too dark on the top!!


Any comments welcome.

Many tanks in advance

Ben

[GoncaloP]

what happens if you use a black color as diffuse? Instead of white...

Gonçalo

[3dben]

It doesnt change anything. (applied for the glass and the wine)

ben

[GoncaloP]

Can you post the scene?

Gonçalo

[winberg]

well, to get "correct" shadows from the glass, you need to set the fog color to something other than white..A light grey would be enough, play around to see..

The only way I could get "correct" ior of the wine and the glass, was to actually remove the glass where it meets the wine, so the rays hits the glass one time, and then hits the wine, instead of two times glass then wine..

-Tom

[losbellos]

interesting issue, but there have been some people who have done this and they didnt say anythink like this, as far as I remember, i'll try this today.

[restoeboemi]

nice result winberg, but what do u mean "remove the glass where it meets the wine" ?

[b-spline]

great explanation!
please, would you post GLASS material parameters?

[3dben]

I can't post my scene neither the glass material now. I will do it on the evening.

My scene is really basic, the glass is defined in the same way as the wine.
So it's ior is set to 1.6 and the fog color is a pure white.

I thought about "removing the glass where it meets the wine" but I found it not really suitable.

Anothers ideas ???
thanks

[losbellos]

check this, he has managed it without geometry and shadow problem. Look after, he maybe can help you.

http://www.vray.info/entry.asp?entryID=68

[flipside]

Yes but his glass and liquid look wrong. Look at tom's image, that looks correct and is indeed the only way I found to get correct look of the liquid on the glass sides.

[losbellos]

ah yes.

[winberg]

here is an image explaining what I meant earlier..

I also did some more experimenting, and came up with an error that I cant get rid of.
Trying to mix 2 materials, one "normal" glass, and one "frosted" type, I get black borders around the bounderies of the two materials..
Anyone experienced this?..




-Tom

[restoeboemi]

thx alot Tom!

[3dben]

So it's not possible to make a simple glass filled with liquid without a big fake? i'm a little bit disapointed, it should work. Is it a bug or is it the some with other renderers ?