diff options
Diffstat (limited to 'core/math/random_pcg.h')
| -rw-r--r-- | core/math/random_pcg.h | 15 |
1 files changed, 12 insertions, 3 deletions
diff --git a/core/math/random_pcg.h b/core/math/random_pcg.h index 230eb9a11b..0d1b311c0d 100644 --- a/core/math/random_pcg.h +++ b/core/math/random_pcg.h @@ -31,6 +31,8 @@ #ifndef RANDOM_PCG_H #define RANDOM_PCG_H +#include <math.h> + #include "core/math/math_defs.h" #include "thirdparty/misc/pcg.h" @@ -38,18 +40,18 @@ class RandomPCG { pcg32_random_t pcg; uint64_t current_seed; // seed with this to get the same state + uint64_t current_inc; public: static const uint64_t DEFAULT_SEED = 12047754176567800795U; static const uint64_t DEFAULT_INC = PCG_DEFAULT_INC_64; static const uint64_t RANDOM_MAX = 0xFFFFFFFF; - RandomPCG(uint64_t p_seed = DEFAULT_SEED, uint64_t p_inc = PCG_DEFAULT_INC_64); + RandomPCG(uint64_t p_seed = DEFAULT_SEED, uint64_t p_inc = DEFAULT_INC); _FORCE_INLINE_ void seed(uint64_t p_seed) { current_seed = p_seed; - pcg.state = p_seed; - pcg32_random_r(&pcg); // Force changing internal state to avoid initial 0 + pcg32_srandom_r(&pcg, current_seed, current_inc); } _FORCE_INLINE_ uint64_t get_seed() { return current_seed; } @@ -61,6 +63,13 @@ public: _FORCE_INLINE_ double randd() { return (double)rand() / (double)RANDOM_MAX; } _FORCE_INLINE_ float randf() { return (float)rand() / (float)RANDOM_MAX; } + _FORCE_INLINE_ double randfn(double p_mean, double p_deviation) { + return p_mean + p_deviation * (cos(Math_TAU * randd()) * sqrt(-2.0 * log(randd()))); // Box-Muller transform + } + _FORCE_INLINE_ float randfn(float p_mean, float p_deviation) { + return p_mean + p_deviation * (cos(Math_TAU * randf()) * sqrt(-2.0 * log(randf()))); // Box-Muller transform + } + double random(double p_from, double p_to); float random(float p_from, float p_to); real_t random(int p_from, int p_to) { return (real_t)random((real_t)p_from, (real_t)p_to); } |