elias/strudel
1
0
Fork 0
mirror of https://github.com/eliasstepanik/strudel.git synced 2026-01-11 13:48:40 +00:00
Code Issues Packages Projects Releases Wiki Activity

add brand (boolean rand) and brandBy

Browse Source
This commit is contained in:
alex 2022-04-15 15:05:30 +01:00
parent b674014377
commit 19f7dc1657
1 changed files with 17 additions and 14 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

31
packages/core/signal.mjs
View File

@ -29,23 +29,22 @@ export const square2 = square._toBipolar();
export const tri = fastcat(isaw, saw);
export const tri2 = fastcat(isaw2, saw2);
// random signals
const xorwise = x => {
const a = (x << 13) ^ x
const b = (a >> 17) ^ a
return (b << 5) ^ b
}
const xorwise = (x) => {
const a = (x << 13) ^ x;
const b = (a >> 17) ^ a;
return (b << 5) ^ b;
};
// stretch 300 cycles over the range of [0,2**29 == 536870912) then apply the xorshift algorithm
const _frac = x => x - Math.trunc(x);
const _frac = (x) => x - Math.trunc(x);
const timeToIntSeed = x => xorwise(Math.trunc(_frac(x / 300) * 536870912));
const timeToIntSeed = (x) => xorwise(Math.trunc(_frac(x / 300) * 536870912));
const intSeedToRand = x => (x % 536870912) / 536870912;
const intSeedToRand = (x) => (x % 536870912) / 536870912;
const timeToRand = x => intSeedToRand(timeToIntSeed(x));
const timeToRand = (x) => intSeedToRand(timeToIntSeed(x));
const timeToRandsPrime = (seed, n) => {
const result = [];
@ -53,9 +52,13 @@ const timeToRandsPrime = (seed, n) => {
result.push(intSeedToRand(seed));
seed = xorwise(seed);
}
return(result);
}
return result;
};
const timeToRands = (t, n) => timeToRandsPrime(timeToIntSeed(t), n)
const timeToRands = (t, n) => timeToRandsPrime(timeToIntSeed(t), n);
export const rand = signal(timeToRand)
export const rand = signal(timeToRand);
export const _brandBy = (p) => rand.fmap((x) => x < p);
export const brandBy = (pPat) => reify(pPat).fmap(_brandBy).innerJoin();
export const brand = _brandBy(0.5);