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@leegrey
Last active November 13, 2023 17:09
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Seeded Perlin Noise in JavaScript - based on original by Ken Perlin
// Seeded Perlin Noise
//
// Based on the original by Ken Perlin:
//
// http://mrl.nyu.edu/~perlin/noise/
// http://mrl.nyu.edu/~perlin/paper445.pdf
//
// Seeding function based on code from:
// http://techcraft.codeplex.com/discussions/264014
//
// translated By Lee Grey 2012 - www.lgrey.com
function PerlinNoiseGenerator( seed ) {
this.p = new Array(512);
//permutation from original by Ken Perlin:
this.permutation;
if( seed ) {
this.setSeed( seed );
} else {
for (var i=0; i < 256 ; i++) {
this.p[256+i] = this.p[i] = this.permutation[i];
}
}
}
PerlinNoiseGenerator.prototype.p;
PerlinNoiseGenerator.prototype.permutation = [
151,160,137,91,90,15,
131,13,201,95,96,53,194,233,7,225,140,36,103,30,69,142,8,99,37,240,21,10,23,
190, 6,148,247,120,234,75,0,26,197,62,94,252,219,203,117,35,11,32,57,177,33,
88,237,149,56,87,174,20,125,136,171,168, 68,175,74,165,71,134,139,48,27,166,
77,146,158,231,83,111,229,122,60,211,133,230,220,105,92,41,55,46,245,40,244,
102,143,54, 65,25,63,161, 1,216,80,73,209,76,132,187,208, 89,18,169,200,196,
135,130,116,188,159,86,164,100,109,198,173,186, 3,64,52,217,226,250,124,123,
5,202,38,147,118,126,255,82,85,212,207,206,59,227,47,16,58,17,182,189,28,42,
223,183,170,213,119,248,152, 2,44,154,163, 70,221,153,101,155,167, 43,172,9,
129,22,39,253, 19,98,108,110,79,113,224,232,178,185, 112,104,218,246,97,228,
251,34,242,193,238,210,144,12,191,179,162,241, 81,51,145,235,249,14,239,107,
49,192,214, 31,181,199,106,157,184, 84,204,176,115,121,50,45,127, 4,150,254,
138,236,205,93,222,114,67,29,24,72,243,141,128,195,78,66,215,61,156,180
];
PerlinNoiseGenerator.prototype.setSeed = function( seed ) {
seed = seed || 1337;
this.permutation = []; //make permutation unique between instances
if( SeededRandomNumberGenerator == undefined ) {
console.log( 'PerlinNoiseGenerator.setSeed() - warning,'
+' SeededRandomNumberGenerator is undefined' );
return;
}
var seedRND = new SeededRandomNumberGenerator();
seedRND.seed = seed;
var i;
for ( i = 0; i < 256; i++) {
this.permutation[i] = i;
}
for ( i = 0; i < 256; i++) {
var k = seedRND.randomIntRange( 0, 256 - i ) + i; //(256 - i) + i;
var l = this.permutation[i];
this.permutation[i] = this.permutation[k];
this.permutation[k] = l;
this.permutation[i + 256] = this.permutation[i];
}
for (var i=0; i < 256 ; i++) {
this.p[256+i] = this.p[i] = this.permutation[i];
}
}
PerlinNoiseGenerator.prototype.noise = function(x, y, z) {
// NOTE: "~~" is a faster approximation of Math.floor()
// Modern browsers inline Math.floor(), so it may actually be faster...
//Find unit cube that contains point
var X = ~~(x) & 255;
var Y = ~~(y) & 255;
var Z = ~~(z) & 255;
//Find relative x,y,z of point in cube
x -= ~~(x);
y -= ~~(y);
z -= ~~(z);
//compute fade curves for each of x,y,z
var u = this.fade(x);
var v = this.fade(y);
var w = this.fade(z);
//hash coordinates of the 8 cube corners
var A = this.p[X ]+Y, AA = this.p[A]+Z, AB = this.p[A+1]+Z;
var B = this.p[X+1]+Y, BA = this.p[B]+Z, BB = this.p[B+1]+Z;
return (
//and add blended results from 8 corners of cube
this.lerp(w, this.lerp(v, this.lerp(u, this.grad(this.p[AA], x, y, z ),
this.grad(this.p[BA], x-1, y, z )),
this.lerp(u, this.grad(this.p[AB], x, y-1, z ),
this.grad(this.p[BB], x-1, y-1, z ))),
this.lerp(v, this.lerp(u, this.grad(this.p[AA+1], x , y , z-1 ),
this.grad(this.p[BA+1], x-1, y, z-1 )),
this.lerp(u, this.grad(this.p[AB+1], x, y-1, z-1 ),
this.grad(this.p[BB+1], x-1, y-1, z-1 ))))
) * 0.5 + 0.5; // return value from 0.0 to 1.0, rather than -1.0 to 1.0
};
PerlinNoiseGenerator.prototype.fade = function(t) {
return t * t * t * (t * (t * 6 - 15) + 10);
}
PerlinNoiseGenerator.prototype.lerp = function( t, a, b) {
return a + t * (b - a);
}
PerlinNoiseGenerator.prototype.grad = function(hash, x, y, z) {
//convert LO 4 bits of hash code into 12 gradient directions
var h = hash & 15;
var u = h<8 ? x : y;
var v = h<4 ? y : h==12||h==14 ? x : z;
return ((h&1) == 0 ? u : -u) + ((h&2) == 0 ? v : -v);
}
@EliezerSolinger
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where is the SeededRandomNumberGenerator???

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