I have a problem combing a scattering media with another media:

When I try to add a second media (to the same interior block),
the first one gets much brighter, even when the second media
doesn't contribute anything at all (like emission 0).
This behavior is the same in 3.1, 3.5 and megapov.

Bug, limitation, intended behavior?

Minimal scene:

camera{
 spherical angle 360
 location -z+y look_at y
}     

light_source{
 <0,1,0>*1000
 color rgb 2
 rotate z*45 rotate y*180
} 

sphere{
 0,1 hollow pigment{color rgbt 1}
 interior{
  media{
   scattering{4,rgb <0.1,0.12,.2>*.01}
  }
  media{emission 0}
 }                         
 scale <10,2,10>*50
}

Lutz-Peter

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"Lutz-Peter Hooge" <lpv### [at] gmxde> wrote in message
news:3f00a814$1@news.povray.org...
> I have a problem combing a scattering media with another media:
>

I can confirm the effect you are describing. I've no idea if this is a bug, but
it certainly looks like one.

Does anyone know if this is a known bug/not a bug/an unreported bug?

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I don't think it's been mentioned before, just not sure though.

It actually only needs to be an empty media statement to cause the extra
brightening. I wouldn't expect to see a change like this so I, too, wonder
if it is a fault somehow. Supposed to be additive or multiplicative when a
media exists, yes, but I guess this means it does something beyond that.

Putting a density {rgb 0} into the second media without anything else
doesn't have any affect. Neither does a scattering rgb 0, of course, only a
raised scattering does.

Out of curiousity I added a third empty media statement and further
increased the brightness due to it, so it is cumulative.

Bob H.

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