For the scope of this game, we will observe just a few basic gestures. These are defined by an enum EGestureType in GameGlobals.h as follows:

enum EGestureType
{
  E_GESTURE_NONE = 0,
  E_GESTURE_TAP,
  E_GESTURE_SWIPE_UP,
  E_GESTURE_SWIPE_DOWN,
  E_GESTURE_SWIPE_LEFT,
  E_GESTURE_SWIPE_RIGHT,
};

As you can see, we will observe the player's touches for taps and swipes in four directions: up, down, left and right. A lot of developers have written great code that observes multiple taps, pinch-zoom gestures, panning gestures, and so on. I encourage you to plug them into this class and increase its capabilities.

Without further ado, let's take a look at the class declaration of GestureLayer from the GestureLayer.h file:

class GestureLayer : public CCLayer
{
public:
  GestureLayer();
  ~GestureLayer();

  static GestureLayer* create(CCObject* target, SEL_CallFuncO handler);

  virtual bool init(CCObject* target, SEL_CallFuncO handler);

  // touch listeners
  virtual void...