Merge multi-touch gestures event branch

This is a squashed commit of the SOC2017_GESTURES branch from
https://github.com/prashantkn94/wxWidgets.git

Closes https://github.com/wxWidgets/wxWidgets/pull/551

interface/wx/event.h

@@ -3644,6 +3644,257 @@ public:
     void SetPosition(int pos);    
 };
 
+
+
+/** @class wxGestureEvent
+    This is the base class for all supported gesture events.
+
+    @library{wxcore}
+    @category{events}
+
+    @see wxPanGestureEvent, wxZoomGestureEvent, wxRotateGestureEvent
+
+    @since 3.1.1
+*/
+class wxGestureEvent : public wxEvent
+{
+public:
+    /**
+        Constructor.
+    */
+    wxGestureEvent(wxWindowID winid = 0, wxEventType type = wxEVT_NULL);
+
+    /**
+        Returns the position where the event took effect, in client coordinates: position of Pan event,
+        center of zoom for Zoom event, center of rotation for Rotate event, center of box formed by 2 fingers
+        for Two Finger Tap event and position of the pressed finger for Press and Tap Event.
+    */
+    const wxPoint& GetPosition() const;
+
+    /**
+        Returns true if the event was the first in a gesture sequence.
+    */
+    bool IsGestureStart() const;
+
+    /**
+        Returns true if the event was the last in a gesture sequence.
+    */
+    bool IsGestureEnd() const;
+
+    /**
+        Sets the position where the event took effect, in client coordinates: position of Pan event,
+        center of zoom for Zoom event, center of rotation for Rotate event.
+    */
+    void SetPosition(const wxPoint& pos);
+
+    /**
+        Sets the event to be the first in a gesture sequence.
+    */
+    void SetGestureStart(bool isStart = true);
+
+    /**
+        Sets the event to be the last in a gesture sequence.
+    */
+    void SetGestureEnd(bool isEnd = true);
+};
+
+
+/** @class wxPanGestureEvent
+
+    This event is generated when the user moves a finger on the surface.
+
+    wxGTK also generates this event during mouse dragging (mouse motion while a left mouse button is depressed).
+
+    Note that OSX requires the primary mouse button to be pressed while performing the finger movement.
+
+    @beginEventTable{wxPanGestureEvent}
+    @event{EVT_GESTURE_PAN(id, func)}
+        Process a @c wxEVT_GESTURE_PAN.
+    @endEventTable
+
+    @library{wxcore}
+    @category{events}
+
+    @since 3.1.1
+*/
+class wxPanGestureEvent : class wxGestureEvent
+{
+public:
+    /**
+        Constructor.
+    */
+    wxPanGestureEvent(wxWindowID winid = 0);
+
+    /**
+        Returns the horizontal component of the distance covered since the previous Pan event.
+    */
+    int GetDeltaX() const;
+
+    /**
+        Returns the vertical component of the distance covered since the previous Pan event.
+    */
+    int GetDeltaY() const;
+
+    /**
+        Sets the horizontal component of the distance covered since the previous Pan event.
+    */
+    int SetDeltaX(int DeltaX);
+
+    /**
+        Sets the vertical component of the distance covered since the previous Pan event.
+    */
+    int SetDeltaY(int DeltaY);
+};
+
+
+/** @class wxZoomGestureEvent
+
+    This event is generated when two fingers pinch the surface to zoom in or out.
+
+    @beginEventTable{wxZoomGestureEvent}
+    @event{EVT_GESTURE_ZOOM(id, func)}
+        Process a @c wxEVT_GESTURE_ZOOM.
+    @endEventTable
+
+    @library{wxcore}
+    @category{events}
+
+    @since 3.1.1
+*/
+class wxZoomGestureEvent : public wxGestureEvent
+{
+public:
+    /**
+        Constructor.
+    */
+    wxZoomGestureEvent(wxWindowID windid = 0);
+
+    /**
+        Returns the zoom Factor since the gesture started. Hence, starting of the gesture
+        is considered as 1:1. A value greater than 1.0 means we should enlarge
+        (or zoom in), a value less than 1.0 means we should shrink (or zoom out).
+    */
+    double GetZoomFactor() const;
+
+    /**
+        Sets the zoom Factor.
+    */
+    double SetZoomFactor() const;
+};
+
+
+/** @class wxRotateGestureEvent
+
+    This event is generated when two fingers move in opposite directions on the surface.
+
+    @beginEventTable{wxRotateGestureEvent}
+    @event{EVT_GESTURE_ROTATE(id, func)}
+        Process a @c wxEVT_GESTURE_ROTATE.
+    @endEventTable
+
+    @library{wxcore}
+    @category{events}
+
+    @since 3.1.1
+*/
+class wxRotateGestureEvent : public wxGestureEvent
+{
+public:
+    /**
+        Constructor.
+    */
+    wxRotateGestureEvent(wxWindowID windid = 0);
+
+    /**
+        Returns the total angle of rotation in radians in clockwise direction since the
+        gesture was first started i.e. when IsGestureStart() returned true. This value is always
+        greater than or equal to zero.
+    */
+    double GetRotationAngle() const;
+
+     /**
+        Sets the total angle of rotation in radians in clockwise direction since the
+        gesture was first started i.e. when IsGestureStart() returned true. This value is always
+        greater than or equal to zero.
+    */
+    void SetRotationAngle(double rotationAngle);
+};
+
+/** @class wxTwoFingerTapEvent
+
+    This event is generated when two fingers touch the surface at the same time.
+
+    @beginEventTable{wxTwoFingerTapEvent}
+    @event{EVT_TWO_FINGER_TAP(id, func)}
+        Process a @c wxEVT_TWO_FINGER_TAP.
+    @endEventTable
+
+    @library{wxcore}
+    @category{events}
+
+    @since 3.1.1
+*/
+class wxTwoFingerTapEvent : public wxGestureEvent
+{
+public:
+    /**
+        Constructor.
+    */
+    wxTwoFingerTapEvent(wxWindowID windid = 0);
+};
+
+/** @class wxLongPressEvent
+
+    This event is generated when one finger touches the surface and remains stationary.
+
+    Note that currently it is only generated under wxGTK and wxOSX.
+
+    wxGTK also generates this event when left mouse button is being pressed for some minimum duration of time.
+
+    @beginEventTable{wxLongPressEvent}
+    @event{EVT_LONG_PRESS(id, func)}
+        Process a @c wxEVT_LONG_PRESS.
+    @endEventTable
+
+    @library{wxcore}
+    @category{events}
+
+    @since 3.1.1
+*/
+class wxLongPressEvent : public wxGestureEvent
+{
+public:
+    /**
+        Constructor.
+    */
+    wxLongPressEvent(wxWindowID windid = 0);
+};
+
+/** @class wxPressAndTapEvent
+
+    This event is generated when the user press the surface with one finger and taps with another.
+
+    Note that once started the event will also be generated when the finger that was pressed moves on surface.
+
+    @beginEventTable{wxPressAndTapEvent}
+    @event{EVT_PRESS_AND_TAP(id, func)}
+        Process a @c wxEVT_PRESS_AND_TAP.
+    @endEventTable
+
+    @library{wxcore}
+    @category{events}
+
+    @since 3.1.1
+*/
+class wxPressAndTapEvent : public wxGestureEvent
+{
+public:
+    /**
+        Constructor.
+    */
+    wxPressAndTapEvent(wxWindowID windid = 0);
+};
+
 #endif // wxUSE_GUI
 
 #if wxUSE_BASE