p5.js Question

var img, pg;

var canvasOfset = 10;

var fillColor;

var drawn = false;

​

function preload() {

  img = loadImage('http://cdni.pageflow.codevise.de/main/video_files/posters/000/000/370/v3/medium/poster-0.JPG');

}

​

​

​

function setup() {

  createCanvas(windowWidth - canvasOfset, windowHeight - canvasOfset);

  pg = createGraphics(width, height);

  pg.image(img, 0, 0, width, height);

}

​

​

function draw() {

  pg.loadPixels();

  rectMode(CENTER);

  var numberOfRands = 100;

  var d = pixelDensity();

  for (var j = 0; j < numberOfRands; j += 4) {

    var off = random(width * height);

    var fillColor = color(pg.pixels[off], pg.pixels[off + 1], pg.pixels[off + 2], pg.pixels[off + 3]);

    for (var i = 0; i < random(120, 1600); i += 4) {

      pg.pixels[off + i] = color(fillColor);

      pg.pixels[off + i + 1] = green(fillColor);

      pg.pixels[off + i + 2] = blue(fillColor);

      pg.pixels[off + i + 3] = alpha(fillColor);

    }

  }

​

  pg.updatePixels();

  image(pg, 0, 0, width, height);

}

​

​

​

function windowResized() {

  resizeCanvas(windowWidth - canvasOfset, windowHeight - canvasOfset);

}