Seeded Perlin Noise in JavaScript - based on original by Ken Perlin

PerlinNoiseGenerator.js

// 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);
}

where is the SeededRandomNumberGenerator???