mirror of
https://github.com/ReMinecraftPE/mcpe.git
synced 2025-01-23 17:52:10 -05:00
110 lines
2.5 KiB
C++
110 lines
2.5 KiB
C++
/********************************************************************
|
|
Minecraft: Pocket Edition - Decompilation Project
|
|
Copyright (C) 2023 iProgramInCpp
|
|
|
|
Random.cpp
|
|
|
|
The following code is licensed under the following license:
|
|
< no license yet :( >
|
|
********************************************************************/
|
|
|
|
#include "Utils.hpp"
|
|
#include "Random.hpp"
|
|
|
|
/* Period parameters */
|
|
#define N 624
|
|
#define M 397
|
|
#define MATRIX_A 0x9908b0dfUL /* constant vector a */
|
|
#define UPPER_MASK 0x80000000UL /* most significant w-r bits */
|
|
#define LOWER_MASK 0x7fffffffUL /* least significant r bits */
|
|
|
|
Random::Random(long seed)
|
|
{
|
|
setSeed(seed);
|
|
}
|
|
|
|
void Random::setSeed(long seed)
|
|
{
|
|
rseed = seed;
|
|
mti = N + 1;
|
|
init_genrand(seed);
|
|
}
|
|
|
|
/* initializes mt[N] with a seed */
|
|
void Random::init_genrand(unsigned long s)
|
|
{
|
|
mt[0] = s & 0xffffffffUL;
|
|
for (mti = 1; mti < N; mti++) {
|
|
mt[mti] =
|
|
(1812433253UL * (mt[mti - 1] ^ (mt[mti - 1] >> 30)) + mti);
|
|
/* See Knuth TAOCP Vol2. 3rd Ed. P.106 for multiplier. */
|
|
/* In the previous versions, MSBs of the seed affect */
|
|
/* only MSBs of the array mt[]. */
|
|
/* 2002/01/09 modified by Makoto Matsumoto */
|
|
mt[mti] &= 0xffffffffUL;
|
|
/* for >32 bit machines */
|
|
}
|
|
}
|
|
|
|
int Random::nextInt(int max)
|
|
{
|
|
return int(genrand_int32() % unsigned(max));
|
|
}
|
|
|
|
// Returns a number from 0 to n (excluding n)
|
|
unsigned int Random::genrand_int32()
|
|
{
|
|
unsigned long y;
|
|
static unsigned long mag01[2]={0x0UL, MATRIX_A};
|
|
/* mag01[x] = x * MATRIX_A for x=0,1 */
|
|
|
|
if (mti >= N) { /* generate N words at one time */
|
|
int kk;
|
|
|
|
if (mti == N+1) /* if init_genrand() has not been called, */
|
|
init_genrand(5489UL); /* 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 & 0x1UL];
|
|
}
|
|
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 & 0x1UL];
|
|
}
|
|
y = (mt[N-1]&UPPER_MASK)|(mt[0]&LOWER_MASK);
|
|
mt[N-1] = mt[M-1] ^ (y >> 1) ^ mag01[y & 0x1UL];
|
|
|
|
mti = 0;
|
|
}
|
|
|
|
y = mt[mti++];
|
|
|
|
/* Tempering */
|
|
y ^= (y >> 11);
|
|
y ^= (y << 7) & 0x9d2c5680UL;
|
|
y ^= (y << 15) & 0xefc60000UL;
|
|
y ^= (y >> 18);
|
|
|
|
return y;
|
|
}
|
|
|
|
float Random::nextFloat()
|
|
{
|
|
return float(genrand_real2());
|
|
}
|
|
|
|
double Random::genrand_real2()
|
|
{
|
|
return double(genrand_int32()) * (1.0 / 4294967296.0);
|
|
}
|
|
|
|
long Random::nextLong()
|
|
{
|
|
return long(genrand_int32() >> 1);
|
|
}
|
|
|
|
int Random::nextInt()
|
|
{
|
|
return int(genrand_int32() >> 1);
|
|
}
|