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Diffstat (limited to 'intern/moto/intern/MT_random.cpp')
| -rwxr-xr-x | intern/moto/intern/MT_random.cpp | 142 |
1 files changed, 142 insertions, 0 deletions
diff --git a/intern/moto/intern/MT_random.cpp b/intern/moto/intern/MT_random.cpp new file mode 100755 index 00000000000..72e7c373201 --- /dev/null +++ b/intern/moto/intern/MT_random.cpp @@ -0,0 +1,142 @@ +/** + * $Id$ + * ***** BEGIN GPL/BL DUAL LICENSE BLOCK ***** + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. The Blender + * Foundation also sells licenses for use in proprietary software under + * the Blender License. See http://www.blender.org/BL/ for information + * about this. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software Foundation, + * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + * + * The Original Code is Copyright (C) 2001-2002 by NaN Holding BV. + * All rights reserved. + * + * The Original Code is: all of this file. + * + * Contributor(s): none yet. + * + * ***** END GPL/BL DUAL LICENSE BLOCK ***** + */ + +/* A C-program for MT19937: Real number version */ + +/* genrand() generates one pseudorandom real number (double) */ +/* which is uniformly distributed on [0,1]-interval, for each */ +/* call. sgenrand(seed) set initial values to the working area */ +/* of 624 words. Before genrand(), sgenrand(seed) must be */ +/* called once. (seed is any 32-bit integer except for 0). */ +/* Integer generator is obtained by modifying two lines. */ +/* Coded by Takuji Nishimura, considering the suggestions by */ +/* Topher Cooper and Marc Rieffel in July-Aug. 1997. */ + +/* This library is free software; you can redistribute it and/or */ +/* modify it under the terms of the GNU Library General Public */ +/* License as published by the Free Software Foundation; either */ +/* version 2 of the License, or (at your option) any later */ +/* version. */ +/* This library is distributed in the hope that it will be useful, */ +/* but WITHOUT ANY WARRANTY; without even the implied warranty of */ +/* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. */ +/* See the GNU Library General Public License for more details. */ +/* You should have received a copy of the GNU Library General */ +/* Public License along with this library; if not, write to the */ +/* Free Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA */ +/* 02111-1307 USA */ + +/* Copyright (C) 1997 Makoto Matsumoto and Takuji Nishimura. */ +/* When you use this, send an email to: matumoto@math.keio.ac.jp */ +/* with an appropriate reference to your work. */ + +#include "MT_random.h" + +/* Period parameters */ +#define N 624 +#define M 397 +#define MATRIX_A 0x9908b0df /* constant vector a */ +#define UPPER_MASK 0x80000000 /* most significant w-r bits */ +#define LOWER_MASK 0x7fffffff /* least significant r bits */ + +/* Tempering parameters */ +#define TEMPERING_MASK_B 0x9d2c5680 +#define TEMPERING_MASK_C 0xefc60000 +#define TEMPERING_SHIFT_U(y) (y >> 11) +#define TEMPERING_SHIFT_S(y) (y << 7) +#define TEMPERING_SHIFT_T(y) (y << 15) +#define TEMPERING_SHIFT_L(y) (y >> 18) + +static unsigned long mt[N]; /* the array for the state vector */ +static int mti = N+1; /* mti==N+1 means mt[N] is not initialized */ + +/* initializing the array with a NONZERO seed */ +void MT_srand(unsigned long seed) +{ + /* setting initial seeds to mt[N] using */ + /* the generator Line 25 of Table 1 in */ + /* [KNUTH 1981, The Art of Computer Programming */ + /* Vol. 2 (2nd Ed.), pp102] */ + mt[0] = seed & 0xffffffff; + for (mti = 1; mti < N; mti++) + mt[mti] = (69069 * mt[mti-1]) & 0xffffffff; +} + +unsigned long MT_rand() +{ + static unsigned long mag01[2] = { 0x0, MATRIX_A }; + /* mag01[x] = x * MATRIX_A for x=0,1 */ + + unsigned long y; + + if (mti >= N) { /* generate N words at one time */ + int kk; + + if (mti == N+1) /* if sgenrand() has not been called, */ + MT_srand(4357); /* a default initial seed is used */ + + for (kk = 0; kk < N - M; kk++) { + y = (mt[kk] & UPPER_MASK) | (mt[kk+1] & LOWER_MASK); + mt[kk] = mt[kk+M] ^ (y >> 1) ^ mag01[y & 0x1]; + } + for (; kk < N-1; kk++) { + y = (mt[kk] & UPPER_MASK) | (mt[kk+1] & LOWER_MASK); + mt[kk] = mt[kk+(M-N)] ^ (y >> 1) ^ mag01[y & 0x1]; + } + y = (mt[N-1] & UPPER_MASK) | (mt[0] & LOWER_MASK); + mt[N-1] = mt[M-1] ^ (y >> 1) ^ mag01[y & 0x1]; + + mti = 0; + } + + y = mt[mti++]; + y ^= TEMPERING_SHIFT_U(y); + y ^= TEMPERING_SHIFT_S(y) & TEMPERING_MASK_B; + y ^= TEMPERING_SHIFT_T(y) & TEMPERING_MASK_C; + y ^= TEMPERING_SHIFT_L(y); + + return y; +} + +#undef N +#undef M +#undef MATRIX_A +#undef UPPER_MASK +#undef LOWER_MASK + +/* Tempering parameters */ +#undef TEMPERING_MASK_B +#undef TEMPERING_MASK_C +#undef TEMPERING_SHIFT_U +#undef TEMPERING_SHIFT_S +#undef TEMPERING_SHIFT_T +#undef TEMPERING_SHIFT_L + |