title: Moving GPUImage Layer with Finger
body: <p>I have a base <code>GPUImagePicture (Layer 1)</code> and then another <code>GPUImagePicture (Layer 2)</code> that I have added a bunch of <code>filters</code> to. </p>
  
  <p>When I put them together into one image they look fine but what I would like to do is move <code>Layer 2</code> with my finger to different positions on <code>Layer 1</code>. Is this possible without using something like <code>Cocos2D</code>?</p>