var num = 30;
var w = c.canvas.width;
var h = c.canvas.height;
for (var i = 0; i < num; i = i + 1) {
var x = i * w / (num - 1);
var y = i * h / (num - 1);
c.strokeStyle = randomRGBA();
drawLine(0, y, x, h);
c.strokeStyle = randomRGBA();
drawLine(x, 0, w, y);
}
function randomRGBA() {
var r = randInt(255);
var g = randInt(255);
var b = randInt(255);
var a = Math.random();
var rgba = [r,g,b,a].join(",");
return "rgba(" + rgba + ")";
}
function randInt(limit) {
var x = Math.random() * limit;
return Math.floor(x);