Last weekend I've encountered a strange behavior in the official Pov 3.1 for Windows which I would take for an error.

If you define a layered media and transform it later on, only the first media after the define is transformed. The other media are not affected by the transform, but are rendered beside this correctly.

The following code shows exemplary the error for 'translate', but it als occurs for 'scale'. For all other transforms I didn' t test it, but I think it will occur for most of them.

However you could work around this error by declaring the multilayer media as single medias and combine them transformed as needed in the object, but for very complex medias this would cancel the advantage of defines to handle them as one unit, especially if you use the same media multiple times but differently transformed.

Your Axel Baune

PS: By the way: Pov-Ray is a great work.

----- Example code --------

// declare multilayered media

#declare med = media {
  emission <1,0,0>
  density {
     spherical
  }
}
media {
  emission <0,0,1>
  density {
     spherical
  }
}

// use declared media

sphere { 0, 1
  texture { pigment rgbt 1 }
  interior {
     media {
        med
        translate <1,0,0>
     }
  }
}

----- Used Resourcen -----

Pov:Pov-Ray 3.1 for Windows (official)

CPU: AMD K6-2 300 3D Now

OS: Windows 95B with USB Support

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Axel Baune                                            Phone:  +49 731 502 4242 
Department of Neural Information Processing             Fax:  +49 731 502 4156
University of Ulm                                      
89069 Ulm                            email: abaune@neuro.informatik.uni-ulm.de
Germany                            URL (privat): http://www.uni-ulm.de/~abaune
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