Mandelbrot Web Worker

mandelbrot.js

xMax = window.innerWidth ;
yMax = window.innerHeight ;

maxThreads = 6 ;

function workerMessage(thread) {
	return '' +thread + ' ' + xMax + " " + yMax ;
}

var b_canvas = document.getElementById("a"); 
var b_context = b_canvas.getContext("2d");

var worker = new Worker("js/mandelbrot_worker.js") ;

for(thread = 1 ; thread <= maxThreads ; thread++) {
	worker.postMessage(workerMessage(thread)) ;
}

worker.onmessage = function(e) {
	data = e.data.split(" ") ;
	
	x = parseInt(data.shift()) ;

	for(y = 0 ; y < yMax ; y++) {
		b_context.fillStyle = data[y] ;
		b_context.fillRect(x, y, 1, 1);
	}
	
	x = x+maxThreads ;
	
	if (x < xMax) {
		worker.postMessage(workerMessage(x))
	}
} ;

mandelbrot_worker.js

function doYLine(screenX, xMax, yMax)
	{
	computedLine = new String ;
	
	computedLine = screenX ;
	
	xZoom = xMax/1000.0/.5 ;
	yZoom = yMax/1000.0/.5 ;
	xThingy = screenX/xMax ;
	
	xOffset = xZoom/4 ;
	yOffset = yZoom/4 ;
	
	for (screenY=0 ; screenY < yMax ; screenY++) {
		x0 = xZoom*xThingy-1 - xOffset ;
		y0 = yZoom*screenY/yMax-1 - yOffset ; 
	
	  x = 0
	  y = 0

	  iteration = 0
	  max_iteration = 50

	  while ( (x*x + y*y <= (2*2))  &&  (iteration < max_iteration) )
	  	{
	    xtemp = x*x - y*y + x0
	    y = 2*x*y + y0

	    x = xtemp

	    iteration = iteration + 1
	  	}

	  if (iteration == max_iteration) {
			computedLine += " rgb(0,0,0)"
			}
		else {
			computedLine += " rgb(" + parseInt((iteration/max_iteration)*255+30) + ",10,10)" ;
			}
	}
	
	return computedLine;
}

onmessage = function(event) {
	m = event.data.split(" ") ;
	
 	line = doYLine(parseInt(m[0]), parseInt(m[1]), parseInt(m[2])) ;
	
	postMessage(line) ;
} ;