code: public void pinchToZoom(PointF startPoint1, PointF startPoint2, PointF endPoint1, PointF endPoint2)
  	{
  		if(config.commandLogging){
  			Log.d(config.commandLoggingTag, "pinchToZoom("+startPoint1+", "+startPoint2+", "+endPoint1+", "+endPoint2+")");
  		}
  		
  		if (android.os.Build.VERSION.SDK_INT < 14){
  			throw new RuntimeException("pinchToZoom() requires API level >= 14");
  		}
  		zoomer.generateZoomGesture(startPoint1, startPoint2, endPoint1, endPoint2);
  	}
docs: Zooms in or out if startPoint1 and startPoint2 are larger or smaller then endPoint1 and endPoint2. Requires API level >= 14.
  
  @param startPoint1 First "finger" down on the screen
  @param startPoint2 Second "finger" down on the screen
  @param endPoint1 Corresponding ending point of startPoint1
  @param endPoint2 Corresponding ending point of startPoint2