diff options
| -rw-r--r-- | core/math/random_number_generator.cpp | 1 | ||||
| -rw-r--r-- | core/math/random_number_generator.h | 2 | ||||
| -rw-r--r-- | core/math/random_pcg.h | 9 | ||||
| -rw-r--r-- | doc/classes/RandomNumberGenerator.xml | 11 |
4 files changed, 23 insertions, 0 deletions
diff --git a/core/math/random_number_generator.cpp b/core/math/random_number_generator.cpp index fccc0f72fe..6add00c1d8 100644 --- a/core/math/random_number_generator.cpp +++ b/core/math/random_number_generator.cpp @@ -40,6 +40,7 @@ void RandomNumberGenerator::_bind_methods() { ClassDB::bind_method(D_METHOD("randi"), &RandomNumberGenerator::randi); ClassDB::bind_method(D_METHOD("randf"), &RandomNumberGenerator::randf); + ClassDB::bind_method(D_METHOD("randfn", "mean", "deviation"), &RandomNumberGenerator::randfn, DEFVAL(0.0), DEFVAL(1.0)); ClassDB::bind_method(D_METHOD("randf_range", "from", "to"), &RandomNumberGenerator::randf_range); ClassDB::bind_method(D_METHOD("randi_range", "from", "to"), &RandomNumberGenerator::randi_range); ClassDB::bind_method(D_METHOD("randomize"), &RandomNumberGenerator::randomize); diff --git a/core/math/random_number_generator.h b/core/math/random_number_generator.h index 66c77b8ccf..6b6bcdd2cd 100644 --- a/core/math/random_number_generator.h +++ b/core/math/random_number_generator.h @@ -55,6 +55,8 @@ public: _FORCE_INLINE_ real_t randf_range(real_t from, real_t to) { return randbase.random(from, to); } + _FORCE_INLINE_ real_t randfn(real_t mean = 0.0, real_t deviation = 1.0) { return randbase.randfn(mean, deviation); } + _FORCE_INLINE_ int randi_range(int from, int to) { unsigned int ret = randbase.rand(); return ret % (to - from + 1) + from; diff --git a/core/math/random_pcg.h b/core/math/random_pcg.h index cd721ef4d1..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" @@ -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); } diff --git a/doc/classes/RandomNumberGenerator.xml b/doc/classes/RandomNumberGenerator.xml index 6fa2d44fd0..07c9f2a74b 100644 --- a/doc/classes/RandomNumberGenerator.xml +++ b/doc/classes/RandomNumberGenerator.xml @@ -28,6 +28,17 @@ Generates pseudo-random float between [code]from[/code] and [code]to[/code]. </description> </method> + <method name="randfn"> + <return type="float"> + </return> + <argument index="0" name="mean" type="float" default="0.0"> + </argument> + <argument index="1" name="deviation" type="float" default="1.0"> + </argument> + <description> + Generates normally(gaussian) distributed pseudo-random number, using Box-Muller transform with the specified [code]mean[/code] and a standard [code]deviation[/code]. + </description> + </method> <method name="randi"> <return type="int"> </return> |