title: How can we implement overlay effect in cocos2d for my game
body: <p>We have a guy whose shooting range is denoted by a transparent circle. We want to have overlay affect in that transparent layer, as it works in Photoshop.</p>
  
  <p>Basically that will highlight all the elements which comes in that range.</p>
  
  <p>How can we do the same effect in cocos2d.</p>