Testing Creation of Simplex Noise Textures

gistfile1.js

function createNoiseTexture(width, height) {
	var canvas = document.createElement("canvas");
	canvas.width = width;
	canvas.height = height;
	
	var context = canvas.getContext('2d');
	
	var image = context.createImageData( width, height );
	
	var imageData = image.data;
	
	var simplex = new SimplexNoise();
	
	var now = Date.now();
	var w,h, n;
	var octaves = 3;
	for ( var i = 0, j = 0, l = imageData.length; i < l; i += 4, j ++  ) {
		
		h = Math.floor( j/width );
		w = j % width;
		
		n = 0;
		 
		for (var oi=0; oi < octaves; oi++) {
			var exp = Math.pow(2, oi);
			n += simplex.noise(w/width * exp, h/height* exp) / (exp * 2) ;
		}
		//n /= octaves;
		n = Math.floor(Math.abs(n) * 255);
		//n = Math.floor((simplex.noise(w/width, h/height)+1)/2 * 255);
		imageData[ i ] = n;
		imageData[ i + 1 ] = n;
		imageData[ i + 2 ] = n;
		imageData[ i + 3 ] = 255;
		

	}

	context.putImageData( image, 0, 0 );
	console.log('done', Date.now() - now);
	document.body.appendChild(canvas);
	
	var texture = new THREE.Texture(  canvas  );
	texture.needsUpdate = true; 
	return texture;
}


var texture = createNoiseTexture(1024, 1024);