Jerome M. BERGER <jbe### [at] enstfr> wrote:
: But when you scale a normal
: by 5, the way pov does it is equivalent to scaling by <5, 1, 5>

  Wrong. The slope doesn't change. Thus, the apparent depth is scaled by 5,
not by 1.
  To really scale the apparent depth by 1 instead of 5, the slopes would
have to be scaled by 1/5. Povray does not do this. This is easy to test:
Make an object with a normal modifier. Scale that object 100 times larger
and move the camera and the light source 100 times farther away. If what
you say was true, now the slopes would be 1/100 of the original and the
apparent depth would have not changed, so the normal modifier should be
almost invisible. This, of course, is not so. The slopes are not changed
and the apparent depth gets scaled by 100 too.
  Now make this same test in megapov. What happens is that megapov will
scale the _slopes_ by 100 as well, which means that the apparent depth
of the surface would be 10000 after scaling.

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

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