Well, Tim, just a minute... I think that I'm doing it right now.


mensaje news:41484a80@news.povray.org...
> > With the scale <.25, 1, 1>, how do you calculate the translate <5, 0,
0>?
> > If I put scale 5, how can I know the translate vector?
>
> That's actually pretty simple: first, Povray scales the object, afterwards
> it translates it to <5,0,0>. Since the sphere is already located at the
> origin, the position of the sphere won't change when scaling it. Thus, it
> will be squashed a little, but still be positioned at <0,0,0>. So, if I
want
> to place the sphere at <5,0,0>, I just have to translate it there.
>
> > "for a sphere this is kinda pointless, as you could have placed it at
the
> > origin from the beginning and thus save translating it back to the
> origin:"
> > Can you tray to explain me it again, please?
>
> The same as above: positions of objects only change when they are not
> centered at the origin, since scaling would not only scale the object, but
> also its distance to the origin.
> The sphere requires a center vector and a radius. If the center vector is
> <0,0,0>, the sphere is sitting right on the origin, and scaling it will
only
> affect the size.
>
> But, if you place the center of the sphere somewhere else, scaling would
> also affect the position/center of the sphere. Hence, we need to move it
to
> the origin first, scale it, and move it back, if we want to retain its
> position, but not its size.
>
> Regards,
> Tim
>
> -- 
> "Tim Nikias v2.0"
> Homepage: <http://www.nolights.de>
>
>

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