randiny
Version:
<h1 style="margin-bottom: 0">Randiny</h1> <h2 style="font-size: 14px; margin-top: 0">A pseudo random number generator, capable of generating random numbers, and noise maps.</h2>
176 lines • 6.41 kB
JavaScript
"use strict";
var __importDefault = (this && this.__importDefault) || function (mod) {
return (mod && mod.__esModule) ? mod : { "default": mod };
};
Object.defineProperty(exports, "__esModule", { value: true });
const RandomNumber_1 = __importDefault(require("./RandomNumber"));
class RNG {
constructor(seed) {
this.seed = seed;
this.rollingseed = this.seed;
}
/**
* Returns a pseudo-random number between 0-1. As a RandomNumber class.
*/
nextValue() {
const a = 1664525;
const c = 1013904223;
const m = 2 ** 32;
this.rollingseed = (a * this.rollingseed + c) % m;
return new RandomNumber_1.default(this, this.rollingseed / m);
}
/**
Returns a static capture of the RNG configuration.
*/
capture() {
return {
seed: this.seed,
rollingseed: this.rollingseed,
};
}
fade(t) {
return t * t * t * (t * (t * 6 - 15) + 10);
}
lerp(a, b, t) {
return a + t * (b - a);
}
grad(hash, ...coords) {
switch (coords.length) {
case 1: {
const x = coords[0];
return (hash & 1) === 0 ? x : -x;
}
case 2: {
const [x, y] = coords;
const h = hash & 7;
switch (h) {
case 0: return x + y;
case 1: return -x + y;
case 2: return x - y;
case 3: return -x - y;
case 4: return x;
case 5: return -x;
case 6: return y;
case 7: return -y;
}
return 0;
}
case 3: {
const [x, y, z] = coords;
const h = hash & 15;
const u = h < 8 ? x : y;
const v = h < 4 ? y : h === 12 || h === 14 ? x : z;
return ((h & 1) === 0 ? u : -u) + ((h & 2) === 0 ? v : -v);
}
default:
throw new Error("Invalid dimension for grad()");
}
}
hash(...coords) {
let h = this.seed >>> 0;
for (let i = 0; i < coords.length; i++) {
let k = (coords[i] + i * 374761393) >>> 0;
k *= 0xcc9e2d51;
k = (k << 15) | (k >>> 17);
k *= 0x1b873593;
h ^= k;
h = (h << 13) | (h >>> 19);
h = h * 5 + 0xe6546b64;
}
h ^= coords.length * 4;
h ^= h >>> 16;
h *= 0x85ebca6b;
h ^= h >>> 13;
h *= 0xc2b2ae35;
h ^= h >>> 16;
return h & 255;
}
perlin1D(x) {
const x0 = Math.floor(x);
const x1 = x0 + 1;
const sx = this.fade(x - x0);
const n0 = this.grad(this.hash(x0), x - x0);
const n1 = this.grad(this.hash(x1), x - x1);
const value = this.lerp(n0, n1, sx);
return new RandomNumber_1.default(this, (value + 1) / 2); // normalize to [0,1]
}
perlin2D(x, y) {
const x0 = Math.floor(x), x1 = x0 + 1;
const y0 = Math.floor(y), y1 = y0 + 1;
const sx = this.fade(x - x0);
const sy = this.fade(y - y0);
const n00 = this.grad(this.hash(x0, y0), x - x0, y - y0);
const n10 = this.grad(this.hash(x1, y0), x - x1, y - y0);
const n01 = this.grad(this.hash(x0, y1), x - x0, y - y1);
const n11 = this.grad(this.hash(x1, y1), x - x1, y - y1);
const ix0 = this.lerp(n00, n10, sx);
const ix1 = this.lerp(n01, n11, sx);
const value = this.lerp(ix0, ix1, sy);
return new RandomNumber_1.default(this, (value + 1) / 2);
}
perlin3D(x, y, z) {
const x0 = Math.floor(x), x1 = x0 + 1;
const y0 = Math.floor(y), y1 = y0 + 1;
const z0 = Math.floor(z), z1 = z0 + 1;
const sx = this.fade(x - x0);
const sy = this.fade(y - y0);
const sz = this.fade(z - z0);
const n000 = this.grad(this.hash(x0, y0, z0), x - x0, y - y0, z - z0);
const n100 = this.grad(this.hash(x1, y0, z0), x - x1, y - y0, z - z0);
const n010 = this.grad(this.hash(x0, y1, z0), x - x0, y - y1, z - z0);
const n110 = this.grad(this.hash(x1, y1, z0), x - x1, y - y1, z - z0);
const n001 = this.grad(this.hash(x0, y0, z1), x - x0, y - y0, z - z1);
const n101 = this.grad(this.hash(x1, y0, z1), x - x1, y - y0, z - z1);
const n011 = this.grad(this.hash(x0, y1, z1), x - x0, y - y1, z - z1);
const n111 = this.grad(this.hash(x1, y1, z1), x - x1, y - y1, z - z1);
const ix00 = this.lerp(n000, n100, sx);
const ix01 = this.lerp(n001, n101, sx);
const ix10 = this.lerp(n010, n110, sx);
const ix11 = this.lerp(n011, n111, sx);
const iy0 = this.lerp(ix00, ix10, sy);
const iy1 = this.lerp(ix01, ix11, sy);
const value = this.lerp(iy0, iy1, sz);
return new RandomNumber_1.default(this, (value + 1) / 2);
}
fbm1D(x, octaves = 4, frequency = 0.01, lacunarity = 2, gain = 0.5) {
let total = 0;
let amp = 1;
let freq = frequency;
let max = 0;
for (let i = 0; i < octaves; i++) {
total += this.perlin1D(x * freq).get() * amp;
max += amp;
amp *= gain;
freq *= lacunarity;
}
return new RandomNumber_1.default(this, total / max);
}
fbm2D(x, y, octaves = 4, frequency = 0.01, lacunarity = 2, gain = 0.5) {
let total = 0;
let amp = 1;
let freq = frequency;
let max = 0;
for (let i = 0; i < octaves; i++) {
total += this.perlin2D(x * freq, y * freq).get() * amp;
max += amp;
amp *= gain;
freq *= lacunarity;
}
return new RandomNumber_1.default(this, total / max);
}
fbm3D(x, y, z, octaves = 4, frequency = 0.01, lacunarity = 2, gain = 0.5) {
let total = 0;
let amp = 1;
let freq = frequency;
let max = 0;
for (let i = 0; i < octaves; i++) {
total += this.perlin3D(x * freq, y * freq, z * freq).get() * amp;
max += amp;
amp *= gain;
freq *= lacunarity;
}
return new RandomNumber_1.default(this, total / max);
}
}
exports.default = RNG;
//# sourceMappingURL=RNG.js.map