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Math.random Extension

The goal of this extension is to describe how a random proposal would change with types. This will cover the basic generation tasks like random numbers and seeded randoms with various methods.

Refer to this as I'll base these notes off of it: https://github.com/tc39/proposal-seeded-random

Note: This is a pseudorandom library identical to Math.random and not cryptographically random. It's designed around speed for things like games. Extending the Crypto library later into ECMAScript would probably be ideal to have a wide range of Crypto RNG generation.

Math.random.<T, Method=???>()

The first addition is a generic version of Math.random for the float types:

float16, float32, float64

The second generic argument is a method set to the browser default PRNG method. Not sure how to namespace that. Like Math.PRNG.Default.

Rapidly generating arrays of random numbers in the range [0, 1):

const a: [100].<float32>;
Math.random.<float32>(a);

When used with an integer type it will generate a random integer in their range.

int8, int16, int32, int64
uint8, uint16, uint32, uint64

const a = Math.random.<uint8>();
a; // 0 to 255

Generating a random RGB color:

const a: [3].<uint8>;
Math.random.<uint8>(a);
a; // [100, 20, 25] as an example

Math.random.<T, Method=???>(min: T, max: T)

For generating between a min and max inclusive the following data types are allowed:

int8, int16, int32, int64
uint8, uint16, uint32, uint64
bigint
float16, float32, float64

So to generate an int32 between -5 and 5 you only need to do:

Math.random.<int32>(-5, 5);

Rapidly generating arrays of random numbers in the range [-1, 1]:

const prng = Math.seededRandom.<float32>({ seed: 0 });
const a: [100].<float32>;
prng.random(a, -1, 1);

Could also define Math.random<T, M=???>(max) since function overloading exists.

Math.seededRandom.<T, Method=???>(config)

const prng = Math.seededRandom.<float32>({ seed: 0 });
const i = prng.random(); // [0, 1)
const j = prng.random(-5, 5); // [-5, 5]

Rapidly generating arrays of random numbers:

const prng = Math.seededRandom.<float32>({ seed: 0 });
const a: [100].<float32>;
prng.random(a, -1, 1);

Web Workers

Sharing seeded random across Web Workers isn't allowed. Using an atomic index into an array would work. Or each thread just creates its own seeded random and uses that.

WIP

Extracting state to save is still up for debate. I'd think a standardized [].<uint8> array of binary data would be sufficient for each PRNG method. Basically just need a way that works as nobody is inspecting it probably.