[Computer-go] fast + good RNG

Dave Dyer ddyer at real-me.net
Sun Mar 29 07:42:16 PDT 2015

>Anyway, it's very easy to make a fast PRNG these days. 

A couple words of caution about hacking PNRG.   

Back in the stone age of computing, some mavens from the triple-i movie
group cooked up a "galaxy simulator" which generated pictures of spiral
galaxies based on a numerical model.  The capability to make pictures was 
rare at the time.

The pictures sucked.  After lots of hunting for flaws in the model,
and tweaking it, the real cause for the poor quality was determined to be
that fortran's "random" numbers weren't very good.  Substitute a better
PRNG, and beautiful pictures emerged.


On a similar note, working with a UCT robot for a blokus clone at
boardspace.net, I found that tiny changes in the way PRNG's were used
had measurable effects on the quality of play.  Not necessarily better 
or worse, just different.


So if you're going to hack the PRNG, you should retain the ability
to use a gold standard PRNG instead of your faster-better-cheaper
model, and you should use it once in a while, just to be sure you're
not introducing hidden flaws.

More information about the Computer-go mailing list