Create dissolve effect

dissolve.js

var Canvas = require('canvas'),
    fs = require('fs'),
    pad = require('pad'),
    _ = require('underscore'),
    canvas = new Canvas(256, 256),
    ctx = canvas.getContext('2d');

ctx.antialias = 'none';
var pts = _.range(256 * 256).sort(function() { return Math.random() - 0.5; });

ctx.fillStyle = '#fff';
ctx.fillRect(0, 0, 256, 256);

ctx.fillStyle = '#000';

var f = 8;

for (var i = 0; i < 256 * 256; i++) {
    var tofill = pts.pop();
    ctx.fillRect(Math.floor(tofill / 256), tofill % 256, 1, 1);
    if (i % (256 * 32) === 0) {
        fs.writeFileSync('frames/' + pad(15, (f--) + 'frame.png', '0'), canvas.toBuffer());
    }
}
fs.writeFileSync('frames/' + pad(15, (f--) + 'frame.png', '0'), canvas.toBuffer());