"clipka" <nomail@nomail> wrote:
> "JeffBTX" <nomail@nomail> wrote:
> > 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.
>
> This is for the simple reason that DF3 media does *not* repeat (I guess applying
> some suitable repeat-warp would do the trick), nor does it "auto-center" on the
> container: It always fills just the unit cube from <0,0,0> to <1,1,1>, and
> everything outside is assumed to have the value 0 (even if all voxels in the
> DF3 happen to be set to 1.0).
>
> If you specify the box to match the unit cube, specify the media, and *then*
> translate the whole smash, the translation will be applied to the media as
> well, i.e. "dragging" it with the box, so to speak.
>
>
> No bug here, and hence not "fixed" in 3.7 either.
>
> Though admittedly it might be worth considering to have DF3 repeat by default,
> like with image maps, and instead require the "once" keyword for non-repeating
> operation.

Clipka;
Thank you for your reply. That makes sense to me, and I understand your input.
So basically, whenever using DF3s (if nothing else just to simply things); one
MUST use and visualize unit cubes from 0 to 1. THEN translate to wherever.

The main thing is that I understand your explanation for "why"; thank you.

Warp;
You read too fast.
:p
That is, you read my post too fast.
;p
Less coffee
:o

Specifying the cube from 0 to 1 doesn't cause the "problem". Specifying from
-0.5 to +0.5 is what caused the unexpected results. Clipka pretty much answers
my question.

I very much appreciate the input from this newsgroup... it is a valuable
resource, especially from old-timers to new-bies. (Not that I'm a newbie... its
just that with me, raytracing has been an on-again off-again thing).

- Thanks, Both

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