2.5. Random generator library

The RANDOM module implements pseudo-random number generation using a linear congruential generator with vectorized state (int4). It provides integer, float, and vector random values, as well as geometric sampling (unit vectors, points in spheres and disks).

All functions and symbols are in “random” module, use require to get access to it.

require daslib/random

Example:

require daslib/random

    [export]
    def main() {
        var seed = random_seed(12345)
        print("int: {random_int(seed)}\n")
        print("float: {random_float(seed)}\n")
        print("float: {random_float(seed)}\n")
    }
    // output:
    // int: 7584
    // float: 0.5848567
    // float: 0.78722495

2.5.1. Constants

random::LCG_RAND_MAX = 32767

maximum possible output of random number generator

random::LCG_RAND_MAX_BIG = 1073741823

maximum possible output of random_big_int

2.5.2. Seed and basic generators

• random_big_int (var seed: int4&) : auto

• random_float (var seed: int4&) : auto

• random_float4 (var seed: int4&) : auto

• random_int (var seed: int4&) : auto

• random_int4 (var seed: int4&) : auto

• random_seed (seed: int) : auto

• random_seed2D (var seed: int4&; co: int2; cf: int = 0) : auto

• random_uint (var seed: int4&) : auto

random::random_big_int(seed: int4&) : auto()

random integer 0..32768*32768-1 (LCG_RAND_MAX_BIG)

Arguments

• seed : int4&

random::random_float(seed: int4&) : auto()

random float 0..1

Arguments

• seed : int4&

random::random_float4(seed: int4&) : auto()

random float4, each component is 0..1

Arguments

• seed : int4&

random::random_int(seed: int4&) : auto()

random integer 0..32767 (LCG_RAND_MAX)

Arguments

• seed : int4&

random::random_int4(seed: int4&) : auto()

random int4, each component is 0..32767 (LCG_RAND_MAX)

Arguments

• seed : int4&

random::random_seed(seed: int) : auto()

constructs seed vector out of single integer seed

Arguments

• seed : int

random::random_seed2D(seed: int4&; co: int2; cf: int = 0) : auto()

constructs seed vector out of 2d screen coordinates and frame counter cf

Arguments

• seed : int4&

• co : int2

• cf : int

random::random_uint(seed: int4&) : auto()

random unsigned integer using 3-component LCG, covering full uint range

Arguments

• seed : int4&

2.5.3. Random iterators

• each_random_uint (rnd_seed: int = 13) : iterator<uint>

random::each_random_uint(rnd_seed: int = 13) : iterator<uint>()

infinite generator of random uints initialized with rnd_seed

Arguments

• rnd_seed : int

2.5.4. Specific distributions

• random_in_unit_disk (var seed: int4&) : auto

• random_in_unit_sphere (var seed: int4&) : auto

• random_unit_vector (var seed: int4&) : auto

random::random_in_unit_disk(seed: int4&) : auto()

Returns a random float3 point uniformly distributed inside the unit disk (length <= 1, z=0).

Arguments

• seed : int4&

random::random_in_unit_sphere(seed: int4&) : auto()

Returns a random float3 point uniformly distributed inside the unit sphere (length <= 1).

Arguments

• seed : int4&

random::random_unit_vector(seed: int4&) : auto()

random float3 unit vector (length=1.)

Arguments

• seed : int4&