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    <p>There are much better choices than Mersenne Twister nowadays. Here is a RNG called WELL512, designed by the designers of Mersenne, developed 10 years later, and an all around better choice for games. The code is put in the public domain by Dr. Chris Lomont. He claims this implementation is 40% faster than Mersenne, does not suffer from poor diffusion and trapping when the state contains many 0 bits, and is clearly a lot simpler code. It has a period of 2^512; a PC takes over 10^100 years to cycle through the states, so it is large enough.</p> <p>Here is a paper overviewing PRNGs where I found the WELL512 implementation. <a href="http://www.lomont.org/Math/Papers/2008/Lomont_PRNG_2008.pdf" rel="noreferrer">http://www.lomont.org/Math/Papers/2008/Lomont_PRNG_2008.pdf</a></p> <p>So - faster, simpler, created by the same designers 10 years later, and produces better numbers than Mersenne. How can you go wrong? :)</p> <p><strong>UPDATE (11-18-14)</strong>: Fixed error (changed 0xDA442D20UL to 0xDA442D24UL, as described in the paper linked above).</p> <pre><code>/* initialize state to random bits */ static unsigned long state[16]; /* init should also reset this to 0 */ static unsigned int index = 0; /* return 32 bit random number */ unsigned long WELLRNG512(void) { unsigned long a, b, c, d; a = state[index]; c = state[(index+13)&amp;15]; b = a^c^(a&lt;&lt;16)^(c&lt;&lt;15); c = state[(index+9)&amp;15]; c ^= (c&gt;&gt;11); a = state[index] = b^c; d = a^((a&lt;&lt;5)&amp;0xDA442D24UL); index = (index + 15)&amp;15; a = state[index]; state[index] = a^b^d^(a&lt;&lt;2)^(b&lt;&lt;18)^(c&lt;&lt;28); return state[index]; } </code></pre>
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    1. POWhat is a good random number generator for a game?
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    1. USTyler Streeter
    1. USChris Lomont
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    1. COThat's a good one.
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      1. USNosredna
    2. COI waste one evening to understand why my code doesn't work: on 64 bit machines this code procude 64 bit number! Use `sizeof(unsigned long) * 8`
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      1. USRuggero Turra
    3. CO@wiso, use `sizeof(unsigned long) * 8` instead of which part?
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      1. USShahbaz
 

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