Jim Gould <jim### [at] homecom> wrote:
: I discovered that on a Duron 800, this would
: still probably take about 2 weeks to render, (about 25000 spheres
: differenced against a cylinder.)

  There are several things you can do to speed this up.

  For example, if the entire object was a triangle mesh it would probably
render in some minutes instead of two weeks (well, of course it depends on
reflections and refractions amount, but it would still be a lot faster).
  Figuring out how to (automatically) create a mesh of smooth triangles which
resembles the same object with povray code can be sometimes very difficult,
if not near-to-impossible, but if you can do it, it certainly is worth the
efforts.
  I have done this and it really helps. I had a set of tubes (cylinders and
clipped toruses) forming a complex scene (several millions of cylinders and
toruses). I made two macros which created (open) cylinders and torus
segments with smooth triangles and I recreated the scene with those. The
speed difference was marvelous (a total of more than 30 millions of triangles
rendered in less than 8 minutes at 1024x768 in a P-II 350MHz).

  If you have to use CSG, you may want to see if there's any cheaper way of
achieving the same effect you want. For example sometimes the union of 12
cubes can be faster than 3 cubes differenced from a 4th, the resulting object
being identical.

  With glass objects you may want to experiment with the adc_bailout value.
Setting it larger than the default may speed up the rendering without too
visible artifacts.

-- 
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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