title: How can i find angle between two circle points in cocos2dx
body: <p>I am working in cocos2dx game developing and working on circle gesture detection . I would like to ask how can I find angle between two points.How can i find angle between two points A and B.my ccTouchesMoved event as follows.</p>
  
  <pre><code>void HelloWorld::ccTouchesMoved(CCSet *pTouches, CCEvent *pEvent)
  {
  
      CCLog("Touches moved");
  
      CCTouch *touch = (CCTouch*)pTouches-&gt;anyObject();
  
      location = touch-&gt;getLocation();
  
      location=CCDirector::sharedDirector()-&gt;convertToGL(location);
  
      prevLocation=CCDirector::sharedDirector()-&gt;convertToGL(touch-&gt;getPreviousLocationInView());
  
      deltax=prevLocation.x-location.x;//difference of x
  
      deltay=prevLocation.y-location.x;//difference of y
  
      angle=??// i want this angle using deltax and deltay
  
  }
  </code></pre>
  
  <p><img src="https://i.stack.imgur.com/7lqCE.png" alt=""></p>