RandomNumberGenerator

Inherits: Reference < Object

A class for generating pseudo-random numbers.

Description

RandomNumberGenerator is a class for generating pseudo-random numbers. It currently uses PCG32.

Note: The underlying algorithm is an implementation detail. As a result, it should not be depended upon for reproducible random streams across Godot versions.

To generate a random float number (within a given range) based on a time-dependant seed:

var rng = RandomNumberGenerator.new()
func _ready():
    rng.randomize()
    var my_random_number = rng.randf_range(-10.0, 10.0)

Properties

int seed -6398989897141750821

Methods

float randf ( )
float randf_range ( float from, float to )
float randfn ( float mean=0.0, float deviation=1.0 )
int randi ( )
int randi_range ( int from, int to )
void randomize ( )

Property Descriptions

int seed

Default -6398989897141750821
Setter set_seed(value)
Getter get_seed()

The seed used by the random number generator. A given seed will give a reproducible sequence of pseudo-random numbers.

Note: The RNG does not have an avalanche effect, and can output similar random streams given similar seeds. Consider using a hash function to improve your seed quality if they're sourced externally.

Method Descriptions

float randf ( )

Generates a pseudo-random float between 0.0 and 1.0 (inclusive).

float randf_range ( float from, float to )

Generates a pseudo-random float between from and to (inclusive).

float randfn ( float mean=0.0, float deviation=1.0 )

Generates a normally-distributed pseudo-random number, using Box-Muller transform with the specified mean and a standard deviation. This is also called Gaussian distribution.

int randi ( )

Generates a pseudo-random 32-bit unsigned integer between 0 and 4294967295 (inclusive).

int randi_range ( int from, int to )

Generates a pseudo-random 32-bit signed integer between from and to (inclusive).

void randomize ( )

Setups a time-based seed to generator.

© 2014–2020 Juan Linietsky, Ariel Manzur, Godot Engine contributors
Licensed under the MIT License.
https://docs.godotengine.org/en/3.2/classes/class_randomnumbergenerator.html