Media simulates an exponential absorption process, so if you scale up
and object by x (uniform scale), then you have to scale down the density
by 1 / e^x.  If you use a non-uniform scale, you will probably have a
lot of trouble getting things to work right...

The thing to remember is that media really only works in world
coordinates.  That means that while POV-Ray wants the media to be
defined in object coordinates (before transformations), the process of
sampling will always be in the final transformed coords.

Xander

ryan constantine wrote:
> 
> didn't somebody say that when you scale a media-filled object that the
> media must be scaled by the inverse?  so if you scale the object up or
> down, media should be scaled by 1/scale (notice if you scale down the
> object, the fraction flips automatically to make the media bigger).  try
> it out.  hopefully i'm not in left field.
> 
> How Camp wrote:
> >
> > Well, once again I seem to be a bit confused...
> >
> > I have a simple texture in Moray that uses emission media.  When rendered in
> > the preview mode, it looks just the way I want it to.  However, the object
> > to which I am applying the texture has been scaled considerably (much
> > smaller).  The media does not seem to render the same when the object
> > changes size - it tends to diminish in both intensity and density until
> > there is only a faint hint of anything at all.
> >
> > I have tried to scale the density map as well as the entire texture to no
> > avail.  Would anyone be so kinds as to shed some light on how to alter my
> > media so it will render as I might expect?  I'm relatively confident it is
> > just a matter of transforms somewhere...?
> >
> > - How

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