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-rw-r--r--src/mersenne.cpp76
1 files changed, 0 insertions, 76 deletions
diff --git a/src/mersenne.cpp b/src/mersenne.cpp
deleted file mode 100644
index 70a443149..000000000
--- a/src/mersenne.cpp
+++ /dev/null
@@ -1,76 +0,0 @@
-/* $Id$ */
-
-/** @file mersenne.cpp */
-
-#include "stdafx.h"
-#include "openttd.h"
-
-#ifdef MERSENNE_TWISTER
-
-// Source code for Mersenne Twister.
-// A Random number generator with much higher quality random numbers.
-
-#define N (624) // length of _mt_state vector
-#define M (397) // a period parameter
-#define K (0x9908B0DFU) // a magic constant
-#define hiBit(u) ((u) & 0x80000000U) // mask all but highest bit of u
-#define loBit(u) ((u) & 0x00000001U) // mask all but lowest bit of u
-#define loBits(u) ((u) & 0x7FFFFFFFU) // mask the highest bit of u
-#define mixBits(u, v) (hiBit(u)|loBits(v)) // move hi bit of u to hi bit of v
-
-static uint32 _mt_state[N+1]; // _mt_state vector + 1 extra to not violate ANSI C
-static uint32 *_mt_next; // _mt_next random value is computed from here
-static int _mt_left = -1; // can *_mt_next++ this many times before reloading
-
-void SeedMT(uint32 seed)
-{
- register uint32 x = (seed | 1U) & 0xFFFFFFFFU, *s = _mt_state;
- register int j;
-
- for (_mt_left=0, *s++=x, j=N; --j;
- *s++ = (x*=69069U) & 0xFFFFFFFFU);
- }
-
-
-static uint32 ReloadMT()
- {
- register uint32 *p0=_mt_state, *p2=_mt_state+2, *pM=_mt_state+M, s0, s1;
- register int j;
-
- if (_mt_left < -1)
- SeedMT(4357U);
-
- _mt_left=N-1, _mt_next=_mt_state+1;
-
- for (s0=_mt_state[0], s1=_mt_state[1], j=N-M+1; --j; s0=s1, s1=*p2++)
- *p0++ = *pM++ ^ (mixBits(s0, s1) >> 1) ^ (loBit(s1) ? K : 0U);
-
- for (pM=_mt_state, j=M; --j; s0=s1, s1=*p2++)
- *p0++ = *pM++ ^ (mixBits(s0, s1) >> 1) ^ (loBit(s1) ? K : 0U);
-
- s1=_mt_state[0], *p0 = *pM ^ (mixBits(s0, s1) >> 1) ^ (loBit(s1) ? K : 0U);
- s1 ^= (s1 >> 11);
- s1 ^= (s1 << 7) & 0x9D2C5680U;
- s1 ^= (s1 << 15) & 0xEFC60000U;
- return(s1 ^ (s1 >> 18));
- }
-
-
-uint32 RandomMT()
-{
- uint32 y;
-
- if (--_mt_left < 0)
- return ReloadMT();
-
- y = *_mt_next++;
- y ^= (y >> 11);
- y ^= (y << 7) & 0x9D2C5680U;
- y ^= (y << 15) & 0xEFC60000U;
- return y ^ (y >> 18);
-}
-#else
-
-void SeedMT(uint32 seed) {}
-
-#endif /* MERSENNE_TWISTER */