title: canvas update with drawImage from buffer don't apply actions with drawImage
body: <p>I use the buffering method to update a canvas, the thing is when I draw an Image in my buffer canvas and apply it to the real canvas there is no image at the real canvas. But I can apply anything else to the real canvas.</p>
  
  <p>This is my code:</p>
  
  <pre><code>var ctx = $('#canvas')[0].getContext("2d"),
      width  = $("#canvas").width(),
      height = $("#canvas").height(),
      buffer = $("&lt;canvas&gt;")[0].getContext("2d");
  ctx.canvas.width = width;
  ctx.canvas.height = height;
  buffer.canvas.width = width;
  buffer.canvas.height = height;
  var image = new Image();
  image.src = "img/logo.png";
  $(image).load(function() {
      buffer.drawImage(image, 0, 0);
  });
  ctx.drawImage(buffer.canvas, 0, 0);
  </code></pre>