Added support for wxWidgets magnify events from the Magic Trackpad on OS X

  Committing this separately from the rest to ease making a patch for just this
  functionality in case that it might make it into the trunk.
  
  This can function standalone, though it is less useful without the rest.
  It requires that wxwidgets-3.0.0_macosx_magnify_event.patch be applied to wxWidgets
  It is completely optional; everything is guarded by the USE_OSX_MAGNIFY_EVENT macro.
  
  - Added OnMagnify event handler to EDA_DRAW_PANEL, EDA_3D_CANVAS and the helper for
    EDA_DRAW_PANEL_GAL, WX_VIEW_CONTROLS. This should cover canvases all current tools.
  - Guarded all with USE_OSX_MAGNIFY EVENT feature macro and added support in CMakeLists.txt

3d-viewer/3d_canvas.cpp

@@ -66,6 +66,9 @@ BEGIN_EVENT_TABLE( EDA_3D_CANVAS, wxGLCanvas )
     // mouse events
     EVT_RIGHT_DOWN( EDA_3D_CANVAS::OnRightClick )
     EVT_MOUSEWHEEL( EDA_3D_CANVAS::OnMouseWheel )
+#ifdef USE_OSX_MAGNIFY_EVENT
+    EVT_MAGNIFY( EDA_3D_CANVAS::OnMagnify )    
+#endif
     EVT_MOTION( EDA_3D_CANVAS::OnMouseMove )
 
     // other events
@@ -281,6 +284,21 @@ void EDA_3D_CANVAS::OnMouseWheel( wxMouseEvent& event )
     GetPrm3DVisu().m_Beginy = event.GetY();
 }
 
+#ifdef USE_OSX_MAGNIFY_EVENT
+void EDA_3D_CANVAS::OnMagnify( wxMouseEvent& event )
+{
+    double magnification = (event.GetMagnification() + 1.0f);
+
+    GetPrm3DVisu().m_Zoom /= magnification;
+
+    if( GetPrm3DVisu().m_Zoom <= 0.01 ) {
+        GetPrm3DVisu().m_Zoom = 0.01;
+    }
+
+    DisplayStatus();
+    Refresh( false );
+}
+#endif
 
 void EDA_3D_CANVAS::OnMouseMove( wxMouseEvent& event )
 {

3d-viewer/3d_canvas.h

@@ -115,6 +115,9 @@ public:
     void   OnEraseBackground( wxEraseEvent& event );
     void   OnChar( wxKeyEvent& event );
     void   OnMouseWheel( wxMouseEvent& event );
+#ifdef USE_OSX_MAGNIFY_EVENT
+    void   OnMagnify( wxMouseEvent& event );
+#endif
     void   OnMouseMove( wxMouseEvent& event );
     void   OnRightClick( wxMouseEvent& event );
     void   OnPopUpMenu( wxCommandEvent& event );

CMakeLists.txt

@@ -268,6 +268,10 @@ if( USE_WX_GRAPHICS_CONTEXT )
     add_definitions( -DUSE_WX_GRAPHICS_CONTEXT )
 endif()
 
+if( USE_OSX_MAGNIFY_EVENT )
+    add_definitions( -DUSE_OSX_MAGNIFY_EVENT )
+endif()
+
 
 # Allow user to override the default settings for adding images to menu items.  By default
 # images in menu items are enabled on all platforms except OSX.  This can be over ridden by

common/draw_panel.cpp

@@ -70,6 +70,9 @@ static const int CURSOR_SIZE = 12; ///< Cursor size in pixels
 BEGIN_EVENT_TABLE( EDA_DRAW_PANEL, wxScrolledWindow )
     EVT_LEAVE_WINDOW( EDA_DRAW_PANEL::OnMouseLeaving )
     EVT_MOUSEWHEEL( EDA_DRAW_PANEL::OnMouseWheel )
+#ifdef USE_OSX_MAGNIFY_EVENT
+    EVT_MAGNIFY( EDA_DRAW_PANEL::OnMagnify )
+#endif
     EVT_MOUSE_EVENTS( EDA_DRAW_PANEL::OnMouseEvent )
     EVT_CHAR( EDA_DRAW_PANEL::OnKeyEvent )
     EVT_CHAR_HOOK( EDA_DRAW_PANEL::OnCharHook )
@@ -96,7 +99,11 @@ EDA_DRAW_PANEL::EDA_DRAW_PANEL( EDA_DRAW_FRAME* parent, int id,
     wxASSERT( parent );
 
 #if wxCHECK_VERSION( 2, 9, 5 )
+#ifndef USE_OSX_MAGNIFY_EVENT
     ShowScrollbars( wxSHOW_SB_ALWAYS, wxSHOW_SB_ALWAYS );
+#else
+    ShowScrollbars( wxSHOW_SB_NEVER, wxSHOW_SB_NEVER );
+#endif
     DisableKeyboardScrolling();
 #endif
 
@@ -971,6 +978,32 @@ void EDA_DRAW_PANEL::OnMouseWheel( wxMouseEvent& event )
     event.Skip();
 }
 
+#ifdef USE_OSX_MAGNIFY_EVENT
+void EDA_DRAW_PANEL::OnMagnify( wxMouseEvent& event )
+{
+    // Scale the panel around our cursor position.
+    bool warpCursor = false;
+
+    wxPoint cursorPosition = GetParent()->GetCursorPosition(false);
+    wxPoint centerPosition =  GetParent()->GetScrollCenterPosition();
+    wxPoint vector = centerPosition - cursorPosition;
+
+    double magnification = (event.GetMagnification() + 1.0f);
+    double scaleFactor = GetZoom() / magnification;
+
+    // Scale the vector between the cursor and center point
+    vector.x /= magnification;
+    vector.y /= magnification;
+
+    SetZoom(scaleFactor);
+
+    // Recenter the window along our scaled vector such that the
+    // cursor becomes our scale axis, remaining fixed on screen
+    GetParent()->RedrawScreen(cursorPosition + vector, warpCursor);
+
+    event.Skip();
+}
+#endif
 
 void EDA_DRAW_PANEL::OnMouseEvent( wxMouseEvent& event )
 {

common/draw_panel_gal.cpp

@@ -78,7 +78,11 @@ EDA_DRAW_PANEL_GAL::EDA_DRAW_PANEL_GAL( wxWindow* aParentWindow, wxWindowID aWin
         wxEVT_LEFT_UP, wxEVT_LEFT_DOWN, wxEVT_LEFT_DCLICK,
         wxEVT_RIGHT_UP, wxEVT_RIGHT_DOWN, wxEVT_RIGHT_DCLICK,
         wxEVT_MIDDLE_UP, wxEVT_MIDDLE_DOWN, wxEVT_MIDDLE_DCLICK,
-        wxEVT_MOTION, wxEVT_MOUSEWHEEL, wxEVT_CHAR, KIGFX::WX_VIEW_CONTROLS::EVT_REFRESH_MOUSE
+        wxEVT_MOTION, wxEVT_MOUSEWHEEL, wxEVT_CHAR,
+#ifdef USE_OSX_MAGNIFY_EVENT
+        wxEVT_MAGNIFY,
+#endif        
+        KIGFX::WX_VIEW_CONTROLS::EVT_REFRESH_MOUSE
     };
 
     BOOST_FOREACH( wxEventType eventType, events )

common/gal/opengl/opengl_gal.cpp

@@ -85,6 +85,9 @@ OPENGL_GAL::OPENGL_GAL( wxWindow* aParent, wxEvtHandler* aMouseListener,
     Connect( wxEVT_RIGHT_UP,        wxMouseEventHandler( OPENGL_GAL::skipMouseEvent ) );
     Connect( wxEVT_RIGHT_DCLICK,    wxMouseEventHandler( OPENGL_GAL::skipMouseEvent ) );
     Connect( wxEVT_MOUSEWHEEL,      wxMouseEventHandler( OPENGL_GAL::skipMouseEvent ) );
+#ifdef USE_OSX_MAGNIFY_EVENT
+    Connect( wxEVT_MAGNIFY,         wxMouseEventHandler( OPENGL_GAL::skipMouseEvent ) );
+#endif
 #if defined _WIN32 || defined _WIN64
     Connect( wxEVT_ENTER_WINDOW,    wxMouseEventHandler( OPENGL_GAL::skipMouseEvent ) );
 #endif

common/tool/tool_dispatcher.cpp

@@ -247,6 +247,9 @@ void TOOL_DISPATCHER::DispatchWxEvent( wxEvent& aEvent )
 
     // Mouse handling
     if( type == wxEVT_MOTION || type == wxEVT_MOUSEWHEEL ||
+#ifdef USE_OSX_MAGNIFY_EVENT
+        type == wxEVT_MAGNIFY ||
+#endif
         type == wxEVT_LEFT_DOWN || type == wxEVT_LEFT_UP ||
         type == wxEVT_MIDDLE_DOWN || type == wxEVT_MIDDLE_UP ||
         type == wxEVT_RIGHT_DOWN || type == wxEVT_RIGHT_UP ||

common/view/wx_view_controls.cpp

@@ -39,6 +39,10 @@ WX_VIEW_CONTROLS::WX_VIEW_CONTROLS( VIEW* aView, wxWindow* aParentPanel ) :
 {
     m_parentPanel->Connect( wxEVT_MOTION,
                             wxMouseEventHandler( WX_VIEW_CONTROLS::onMotion ), NULL, this );
+#ifdef USE_OSX_MAGNIFY_EVENT
+    m_parentPanel->Connect( wxEVT_MAGNIFY,
+                            wxMouseEventHandler( WX_VIEW_CONTROLS::onMagnify ), NULL, this );
+#endif
     m_parentPanel->Connect( wxEVT_MOUSEWHEEL,
                             wxMouseEventHandler( WX_VIEW_CONTROLS::onWheel ), NULL, this );
     m_parentPanel->Connect( wxEVT_MIDDLE_UP,
@@ -175,6 +179,16 @@ void WX_VIEW_CONTROLS::onWheel( wxMouseEvent& aEvent )
     aEvent.Skip();
 }
 
+#ifdef USE_OSX_MAGNIFY_EVENT
+void WX_VIEW_CONTROLS::onMagnify( wxMouseEvent& aEvent )
+{
+    // Scale based on the magnification from our underlying magnification event.
+    VECTOR2D anchor = m_view->ToWorld( VECTOR2D( aEvent.GetX(), aEvent.GetY() ) );
+    setScale( m_view->GetScale() * (aEvent.GetMagnification() + 1.0f), anchor );
+
+    aEvent.Skip();
+}
+#endif
 
 void WX_VIEW_CONTROLS::onButton( wxMouseEvent& aEvent )
 {

include/class_drawpanel.h

@@ -256,6 +256,9 @@ public:
      *</p>
      */
     void OnMouseWheel( wxMouseEvent& event );
+#ifdef USE_OSX_MAGNIFY_EVENT
+    void OnMagnify( wxMouseEvent& event );
+#endif
     void OnMouseEvent( wxMouseEvent& event );
     void OnMouseLeaving( wxMouseEvent& event );
     void OnKeyEvent( wxKeyEvent& event );

include/view/wx_view_controls.h

@@ -54,6 +54,9 @@ public:
     /// Handler functions
     void onWheel( wxMouseEvent& aEvent );
     void onMotion( wxMouseEvent& aEvent );
+#ifdef USE_OSX_MAGNIFY_EVENT
+    void onMagnify( wxMouseEvent& aEvent );
+#endif
     void onButton( wxMouseEvent& aEvent );
     void onEnter( wxMouseEvent& WXUNUSED( aEvent ) );
     void onTimer( wxTimerEvent& WXUNUSED( aEvent ) );