This "problem" is very simple and easy to reproduce, so I will not waste
bandwidth posting examples and images.

I am guessing this problem WILL NOT (hopefully) exist in POVRay 3.7+ (I am using
3.6.1 64 bit) (64 bit OS). The guess is due to something that Alain observed,
and comments by some others in another thread or two, and my assumption that
THIS problem is related to ANOTHER problem that I posted on.

Almost every example of media that I have seen involves defining a media
container such as:

box { 0,1 pigment {rgbt 1} hollow
   (... media with DF3)
 translate -0.5
}

(... or a sphere { 0,1 etc.)

I used a small 10 x 10 x 10 DF3 file, it is completely filled with value 255
($FF) voxels. If simple emission is used, it is a "big white cube of glowing
gas". (or absorption with a background, "big box of smoke"; or scattering, "big
box of fog").

This defines a media cube of 1 unit, at x=y=z=0 to x=y=z=1, and then translates
it such that the center of the cube is at the origin.

It renders OK.

BUT if I define the container as:

box { <-0.5,-0.5,-0.5>,<0.5,0.5,0.5> {rgbt 1} hollow
   (... media with DF3)
}

.... with no translation, in other words define the 1 unit box as already being
at the origin, then something very strange happens.

Only the PART of the media showing in the +X +Y +Z quadrant shows. That would be
the "uppermost northeast corner", the quadrant in +x +y +z.

ALL parts that are "BEHIND the origin" do NOT show, such that "only 1/8th" of
the media is showing.

This only happens with a DF3. If I just simply fill the box (at
<-0.5,-0.5,-0.5>,<0.5,0.5,0.5>) with simple media (whether emission, absorption
or scattering), it looks OK.

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