В поисках "не жручих" падающих снежинок

snow = {
    count: 60,
    delay: 10,
    flutter: 0.2,
    wind: 1.0,
    w1: 1,
    minSpeed: 0.3,
    maxSpeed: 4,
    cv: null,
    flakes: [],
    toggle: function() {
        if(window.snowtimer)
            snow.stop();
        else
            snow.start();
    },
    resize: function() {
        snow.cv.width = innerWidth;
        snow.cv.height = innerHeight;
        snow.gt = snow.ct.createLinearGradient(0,0,0,snow.cv.height);
        snow.gt.addColorStop(0.0, '#6666ff');
        snow.gt.addColorStop(1.0, '#ffffff');
        snow.ct.fillStyle = snow.gt;
    },
    start: function() {
        snow.cv = document.createElement('canvas');
        snow.cv.width = snow.cv.height = 10; // set initial size
        snow.cv.id = 'backgroundSnowCanvas';
        document.body.appendChild(snow.cv);
        snow.createFlake();
        snow.ct = snow.cv.getContext('2d'),
        snow.cv.style.position = 'absolute';
        snow.cv.style.top = 0;
        snow.cv.style.left = 0;
        snow.cv.style.zIndex = -1;
        snow.resize();
        var c = snow.count;
        snow.flakes = [];
        do {
            snow.flakes.push(new snow.flake());
        } while(--c);
        snow.ct.fillRect(0,0,snow.cv.width,snow.cv.height);
        window.snowtimer = window.setInterval(snow.draw, snow.delay);
        window.addEventListener('resize',snow.resize);
    },
    stop: function() {
        window.clearInterval(window.snowtimer);
        var c = document.getElementById('backgroundSnowCanvas');
        c.parentNode.removeChild(c);
        window.snowtimer=snow=null;
    },
    draw: function() {
        var ct = snow.ct, f = snow.flakes, c = snow.count;
        ct.fillRect(0,0,snow.cv.width,snow.cv.height);
 
        do {
            if(f[--c].draw(ct) && ++fdone) { };
        } while(c);
        snow.wind += Math.cos(snow.w1++ / 180.0);
    },
    flake: function() {
        this.draw = function(ct) {
            ct.drawImage(snow.flakeImage,this.x + snow.wind,this.y,this.sz,this.sz);
            this.animate();
        };
        this.animate = function() {
            this.y += this.speed;
            this.x += this.flutter * Math.cos(snow.flutter * snow.flutter * this.y);
            if(this.y > innerHeight)
                this.init(1);
        };
        this.init = function(f) {
            this.speed = snow.minSpeed + (Math.random() * (snow.maxSpeed - snow.minSpeed));
            this.sz = ~~(Math.random() * 40) + 20;
            this.flutter = ~~(Math.random() * snow.flutter * (60-this.sz));
            this.x = (Math.random() * (innerWidth + this.sz)) - this.sz;
            this.y = f ? -this.sz : Math.random() * innerHeight;
        };
        this.init();
    },
    createFlake: function() {
        snow.flakeImage = document.createElement('canvas');
        snow.flakeImage.width = snow.flakeImage.height = 440;
        var c = snow.flakeImage.getContext('2d');
        c.fillStyle = '#fff';
        c.translate(20,20);
        c.beginPath();
        c.rect(-5,-20,10,40);
        c.rotate(Math.PI / 3.0);
        c.rect(-5,-20,10,40);
        c.rotate(Math.PI / 3.0);
        c.rect(-5,-20,10,40);
        c.closePath();
        c.fill();
    },
};

background.src = 'https://dl.dropbox.com/s/tfnp41sf8cgfesx/abstract_minimalistic_digital_art.jpg';