Hello everyone,

Someone can perhaps help me. I search to make a good texture for wine
(example wine in a glass). The property of the wine (or other colored
liquid) is that its transparency (filtering) decrease with the
augmentation of the quantity of liquid crossed by the light (I hope do
you understand me). So imagine (you can make the manipulation to night!)
a glass of wine on a table. 50 cm away from your eyes. You will see that
the wine has not the same color everywhere! It is more luminous above
(where the light don't cross to many quantity of wine) and less luminous
at the bottom of the glass (where the light cross more quantity of
liquid).

Povray can similate this? I think that "filter" or "transmit" just
define the quantity of light which go through the object. But I think
that this independant of the volume and the quantity of liquid cross by
the light!

Thanks to answer my question!

If you don't understand me just go to the page:
 http://www.gk.dtu.dk/home/hwj/pictures/caustics.html

And look the glass of Cognac and look the texture for the Cognac! Can
someone do this?

Thanks!


PS: I know that I use the word cross here and this is not the good word!
But I don't remenber the right word!

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I fear the answer is:

"Welcome to the world of media!"

It's the only way I know to simulate such behaviour.

Marc

-- 
Marc Schimmler

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> I fear the answer is:
>
> "Welcome to the world of media!"
>
> It's the only way I know to simulate such behaviour.

Fade_distance and fade_power can do some of the same things, but media
is the more accurate was of doing it.

-Mike

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Mike wrote:
> 
> > I fear the answer is:
> >
> > "Welcome to the world of media!"
> >
> > It's the only way I know to simulate such behaviour.
> 
> Fade_distance and fade_power can do some of the same things, but media
> is the more accurate was of doing it.
> 
> -Mike

Yes. Scattering media is the only way to get the desired result.

Margus

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Thanks all!

Margus Ramst wrote:

> Mike wrote:
> >
> > > I fear the answer is:
> > >
> > > "Welcome to the world of media!"
> > >
> > > It's the only way I know to simulate such behaviour.
> >
> > Fade_distance and fade_power can do some of the same things, but media
> > is the more accurate was of doing it.
> >
> > -Mike
>
> Yes. Scattering media is the only way to get the desired result.
>
> Margus

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Margus Ramst wrote:
> 
> Yes. Scattering media is the only way to get the desired result.
> 
> Margus

A simple absorbing media would be adequate for a clearish wine. 
Scattering would probably be necessary for a darkish red.

PoD.

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Mike <pov### [at] aolcom> wrote in message news:38035E1B.6E3555B5@aol.com...
> Fade_distance and fade_power can do some of the same things, but media
> is the more accurate was of doing it.

Or, if you like patches, you can use fade_distance, fade_power, and my
fade_colour patch, assuming you only want filtering with no scattering.  The
patch is more than twice as fast as media, and somewhat easier to use too.

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Mike <pov### [at] aolcom> wrote:
: Fade_distance and fade_power can do some of the same things, but media
: is the more accurate was of doing it.

  If the only goal is to set the transparency depending on the size of the
object, the fade_distance is the best solution since it's a lot faster to
render.
  The only advantage of using scattering media is that objects can cast
shadows throughout the wine, but it also takes a lot more time to calculate.

-- 
main(i,_){for(_?--i,main(i+2,"FhhQHFIJD|FQTITFN]zRFHhhTBFHhhTBFysdB"[i]
):5;i&&_>1;printf("%s",_-70?_&1?"[]":" ":(_=0,"\n")),_/=2);} /*- Warp -*/

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It can also create a more realistic glow effect. It does look better, but of
course the increased render time is only worth it in close-ups when quality is
of utmost importance.

Margus

Nieminen Juha wrote:
> 
>   If the only goal is to set the transparency depending on the size of the
> object, the fade_distance is the best solution since it's a lot faster to
> render.
>   The only advantage of using scattering media is that objects can cast
> shadows throughout the wine, but it also takes a lot more time to calculate.
> 
> --
> main(i,_){for(_?--i,main(i+2,"FhhQHFIJD|FQTITFN]zRFHhhTBFHhhTBFysdB"[i]
> ):5;i&&_>1;printf("%s",_-70?_&1?"[]":" ":(_=0,"\n")),_/=2);} /*- Warp -*/

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