POV-Ray : Newsgroups : povray.general : media sizes : Re: media sizes Server Time
12 Aug 2024 05:24:30 EDT (-0400)
  Re: media sizes  
From: Bob Hughes
Date: 21 Mar 1999 00:30:31
Message: <36F483F0.30645127@aol.com>
You can do it two different ways.
Either increase 'emission' OR increase the density values by a factor
based upon the change in size.
I tried a 10 times reduction (scale 2.5 rather than 25) on the media
container object and raised the emission 10 times (0.5 rather than
0.05). This makes the same thing as the original.
Oh, and the camera location and look_at numbers were all brought down to
one tenth too (not angle 35, same for it) and also the translate 25*y
changed to 2.5*y to keep the view the same.
'density' can instead be raised 10 times and emission left alone. Skip
scattering altogether if at all possible.

So, it's rather simple. Just go higher or lower as much as you go up or
down in size scale.


portelli wrote:
> 
> I'm afraid I still don't understand.  Do you increase the color values?
> How would you make the pov example,( the fire in the sphere,
> hollow3.pov) to a one unit sized sphere?
> 
> Bob Hughes wrote:
> >
> > It's basically a case of coupling scale in the media object with  the
> > density floats/vectors (and/or scattering {}).
> >
> >  Container {
> >  //etc., etc.
> >    media {
> >  //blah, blah
> >      density { rgb <.1,.2,.3> } //increase if scale decreases
> >    }
> >   scale <.5,.5,.5> //decreased scale, reverse if scaling up
> >  }
> >
> > portelli wrote:
> > >
> > > How do you do this.  I looked in th edocs but it does not tell you
> > > much.  Is there a float to put somewhere?  I tried before  the pattern
> > > type but I get an error.
> > >
> > > Jerry wrote:
> > > >
> > > > In article <36F2D5BE.F86968D1@pilot.msu.edu>, portelli
> > > > <por### [at] pilotmsuedu> wrote:
> > > >
> > > > >        Can media only be put in large containers?  Large with respect to one
> > > > >POV unit.  Most examples I've seen have large spheres with media in
> > > > >them.  Is there a way to scale down the media or containers?  Or do I
> > > > >have to enlarge everything in my scene?
> > > >
> > > > You might end up having to increase the density above 1. Media effects are
> > > > not unit independent. So if you change the size of your media container,
> > > > you'll most likely need to change the density. If you make the object
> > > > bigger, reduce the density; if you make the object smaller, increase the
> > > > density.
> > > >
> > > > I haven't worked with densities above 1, however, and have no idea what
> > > > that will do.
> > > >
> > > > Jerry
> >
> > --
> >  omniVERSE: beyond the universe
> >   http://members.aol.com/inversez/homepage.htm
> >  mailto:inv### [at] aolcom?Subject=PoV-News

-- 
 omniVERSE: beyond the universe
  http://members.aol.com/inversez/homepage.htm
 mailto:inv### [at] aolcom?Subject=PoV-News


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