Hi, I see that Wormux 0.8 uses the "ANSI C" pseudo-random number generator (PRNG): modulo=32768 mutiplicative=1103515245 additive=12345 period=??? (maybe 32768) RAND_MAX=32767
It would be better to use Park-Miller PRNG (also known as "Lehmner PRNG" or "Minimum standard PRNG"): modulo=2147483647 mutiplicative=16807 additive=0 period=2147483646 RAND_MAX=??? (maybe 2147483646) Current generator generates ~15 bits of entropy (in higher bits) at each "clock tick" whereas Park-Miller one does generator ~31 bits. The period is also better: 32768 vs 2147483646. The period is the number of clock ticks before you get the same number. Eg: (n+1) % 10 has as period of 10: it generates 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 0, 1, 2, 3, (...) ;-) I checked Wormux PRNG because I saw two bonus boxes placed at the same position in the same game!? If you choose to change the PRNG, it will break network version compatibility. You have to increment network protocol version. But it should be possible to write a compatibility mode: if any client uses the old protocol, fallback to the old PRNG. Problem: if you want to keep backward compatibility, Wormux source code base will be bigger and bigger... Victor -- Victor Stinner aka haypo http://www.haypocalc.com/blog/ _______________________________________________ Wormux-dev mailing list Wormux-dev@gna.org https://mail.gna.org/listinfo/wormux-dev
