Ron Parker <ron### [at] povrayorg> wrote:
:>  But would inverting the whole 4x4 matrix work as well?

: Of course.  

  It may be crystal-clear to you, but it isn't to me.

  The decision to put the translation as the fourth column of the matrix
can sound quite arbitrary ("Hey, we need some place to put the translation
along with the other transformations. Where should we put it? Perhaps the
most handy way is just to expand the transformation matrix to 4x4 and put
the translation in the extra places").

  However, if the inversion of this matrix works as expected (that is, the
translation is also inverted as it should), then putting the translation
where it is now has a strong mathematical basis. Which is good, of course :)

-- 
main(i,_){for(_?--i,main(i+2,"FhhQHFIJD|FQTITFN]zRFHhhTBFHhhTBFysdB"[i]
):_;i&&_>1;printf("%s",_-70?_&1?"[]":" ":(_=0,"\n")),_/=2);} /*- Warp -*/

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