POV-Ray : Newsgroups : povray.newusers : Media in Povray 3.5 : Re: Media in Povray 3.5 Server Time
31 Jul 2024 02:24:05 EDT (-0400)
  Re: Media in Povray 3.5  
From: Tim Nikias
Date: 14 Feb 2003 09:27:05
Message: <3e4cfcb9@news.povray.org>
> btw, you mention density{rgb 5} - funnily enough I came across this the other
> day(putting a rgb val into a density block). The docs don't really mention that
> this syntax is okay, and I'm slightly mystified as to what it is doing.
>
> is scattering{1, 5} any different from scattering{1,1} density{rgb 5} ?

It is different!
If the volume is denser, this should have different effects, like being
absorbed faster, but since we've got more "particles" to light, it also
gets brighter. Hence I use absorption to compensate for that.
Its quiet difficult to explain, actually, and you should experiment with
it. Here's a code snippet for you to start with (its just the media),
you might want to place it in a sphere on a plane... :-)
And then just fumble with the settings, and modify the code.

//SubSurfaceScattering
#local SSS=2;
#local SSS_Color=<1,0,0>;
#local Extra_Absorb=1.5;

#local SSS_Media=
  media{
   scattering{2,vnormalize(SSS_Color)*SSS}
   absorption (vnormalize(<1,1,1>-SSS_Color)*SSS+Extra_Absorb)
   emission Extra_Absorb*vnormalize(SSS_Color)
   density{rgb SSS_Cloud}
   method 3 intervals 1 samples 10,30
   }



--
Tim Nikias
Homepage: http://www.digitaltwilight.de/no_lights/index.html
Email: Tim### [at] gmxde
"Tom Melly" <tom### [at] tomandlucouk> schrieb im Newsbeitrag
news:3e4cfaac@news.povray.org...
> "Tim Nikias" <tim### [at] gmxde> wrote in message
> news:3e4cea83$1@news.povray.org...
>
> > > 5. Oh, and don't use rgbft 1 for your container's pigment - either rgbf 1 or
> > > rgbt 1
> >
> > I'm curious, why? I'm always using rgbt...
> >
>
> rgbt is fine, so is rgbf - it's rgbft that's a problem - see:
>
> http://news.povray.org/povray.binaries.images/30422/
> and
> http://news.povray.org/povray.general/30421/
>
> btw, you mention density{rgb 5} - funnily enough I came across this the other
> day(putting a rgb val into a density block). The docs don't really mention that
> this syntax is okay, and I'm slightly mystified as to what it is doing.
>
> is scattering{1, 5} any different from scattering{1,1} density{rgb 5} ?
>
>


Post a reply to this message

Copyright 2003-2023 Persistence of Vision Raytracer Pty. Ltd.