Nekar Xenos <vir### [at] iconcoza> wrote:
: Does this mean I won't be able to do a scene that starts on earth, flies up
: into space and look at earth again with the sun included?

  Everything has its price.
  If you wanted variable precision floating point numbers, then povray would
be about 100 times slower than it's now. And we don't want that, do we?
  So we have to use the system's own floating point numbers. They are usually
64 bit long, and you can easily see that with that amount of bits there's a
rather small set of numbers that can be represented ("small" if we are
talking about scale differences comparable to the stars and to individual
atoms). The advantage of using those is the incredible speed boost (which
is natural since the numbers are crunched in hardware).

  And to answer your question: Yes, you can make a scene where you can
fly from the earth to the stars, but you can't have both things at the
same time. You have to first model the earth with big accuracy and the
stars with low accuracy, and as you fly away from one and towards the other
you have to lower the accuracy of the first and increase the accuracy of
the second.
  This only means that you can't have a scene of the surface of the earth
and an extremely powerful telescope looking at the surface of another
planet (not without using tricks, that is).

-- 
char*i="b[7FK@`3NB6>B:b3O6>:B:b3O6><`3:;8:6f733:>::b?7B>:>^B>C73;S1";
main(_,c,m){for(m=32;c=*i++-49;c&m?puts(""):m)for(_=(
c/4)&7;putchar(m),_--?m:(_=(1<<(c&3))-1,(m^=3)&3););}    /*- Warp -*/

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