Implemented support for horizontal mouse wheel scrolling as well as high-precision scrolling on Windows and OS X.

include/SFML/Window/Event.hpp

@@ -102,6 +102,9 @@ public:
     ////////////////////////////////////////////////////////////
     /// \brief Mouse wheel events parameters (MouseWheelMoved)
     ///
+    /// \deprecated This event is deprecated and potentially inaccurate.
+    ///             Use MouseWheelVerticalEvent instead.
+    ///
     ////////////////////////////////////////////////////////////
     struct MouseWheelEvent
     {
@@ -110,6 +113,28 @@ public:
         int y;     ///< Y position of the mouse pointer, relative to the top of the owner window
     };
 
+    ////////////////////////////////////////////////////////////
+    /// \brief Mouse wheel horizontal events parameters (MouseWheelHorizontalMoved)
+    ///
+    ////////////////////////////////////////////////////////////
+    struct MouseWheelHorizontalEvent
+    {
+        float delta; ///< Number of ticks the wheel has moved (positive is left, negative is right)
+        int x;       ///< X position of the mouse pointer, relative to the left of the owner window
+        int y;       ///< Y position of the mouse pointer, relative to the top of the owner window
+    };
+
+    ////////////////////////////////////////////////////////////
+    /// \brief Mouse wheel vertical events parameters (MouseWheelVerticalMoved)
+    ///
+    ////////////////////////////////////////////////////////////
+    struct MouseWheelVerticalEvent
+    {
+        float delta; ///< Number of ticks the wheel has moved (positive is up, negative is down)
+        int x;       ///< X position of the mouse pointer, relative to the left of the owner window
+        int y;       ///< Y position of the mouse pointer, relative to the top of the owner window
+    };
+
     ////////////////////////////////////////////////////////////
     /// \brief Joystick connection events parameters
     ///        (JoystickConnected, JoystickDisconnected)
@@ -178,7 +203,9 @@ public:
         TextEntered,               ///< A character was entered (data in event.text)
         KeyPressed,                ///< A key was pressed (data in event.key)
         KeyReleased,               ///< A key was released (data in event.key)
-        MouseWheelMoved,        ///< The mouse wheel was scrolled (data in event.mouseWheel)
+        MouseWheelMoved,           ///< The mouse wheel was scrolled (data in event.mouseWheel) (deprecated)
+        MouseWheelHorizontalMoved, ///< The mouse wheel was tilted horizontally (data in event.mouseWheelHorizontal)
+        MouseWheelVerticalMoved,   ///< The mouse wheel was scrolled vertically (data in event.mouseWheelVertical)
         MouseButtonPressed,        ///< A mouse button was pressed (data in event.mouseButton)
         MouseButtonReleased,       ///< A mouse button was released (data in event.mouseButton)
         MouseMoved,                ///< The mouse cursor moved (data in event.mouseMove)
@@ -209,7 +236,9 @@ public:
         TextEvent                 text;                 ///< Text event parameters (Event::TextEntered)
         MouseMoveEvent            mouseMove;            ///< Mouse move event parameters (Event::MouseMoved)
         MouseButtonEvent          mouseButton;          ///< Mouse button event parameters (Event::MouseButtonPressed, Event::MouseButtonReleased)
-        MouseWheelEvent      mouseWheel;      ///< Mouse wheel event parameters (Event::MouseWheelMoved)
+        MouseWheelEvent           mouseWheel;           ///< Mouse wheel event parameters (Event::MouseWheelMoved) (deprecated)
+        MouseWheelHorizontalEvent mouseWheelHorizontal; ///< Mouse wheel horizontal event parameters (Event::MouseWheelHorizontalMoved)
+        MouseWheelVerticalEvent   mouseWheelVertical;   ///< Mouse wheel vertical event parameters (Event::MouseWheelVerticalMoved)
         JoystickMoveEvent         joystickMove;         ///< Joystick move event parameters (Event::JoystickMoved)
         JoystickButtonEvent       joystickButton;       ///< Joystick button event parameters (Event::JoystickButtonPressed, Event::JoystickButtonReleased)
         JoystickConnectEvent      joystickConnect;      ///< Joystick (dis)connect event parameters (Event::JoystickConnected, Event::JoystickDisconnected)

src/SFML/Window/OSX/SFOpenGLView.mm

@@ -474,7 +474,7 @@ BOOL isValidTextUnicode(NSEvent* event);
     if (m_requester != 0)
     {
         NSPoint loc = [self cursorPositionFromEvent:theEvent];
-        m_requester->mouseWheelScrolledAt([theEvent deltaY], loc.x, loc.y);
+        m_requester->mouseWheelScrolledAt([theEvent deltaX], [theEvent deltaY], loc.x, loc.y);
     }
 
     // Transmit to non-SFML responder

src/SFML/Window/OSX/WindowImplCocoa.hpp

@@ -164,12 +164,13 @@ public:
     ///
     /// Send the event to SFML WindowImpl class.
     ///
-    /// \param delta scrolling delta
+    /// \param deltaX horizontal scrolling delta
+    /// \param deltaY vertical scrolling delta
     /// \param x mouse x position
     /// \param y mouse y position
     ///
     ////////////////////////////////////////////////////////////
-    void mouseWheelScrolledAt(float delta, int x, int y);
+    void mouseWheelScrolledAt(float deltaX, float deltaY, int x, int y);
 
     ////////////////////////////////////////////////////////////
     /// \brief Mouse In Event - called by the cocoa view object

src/SFML/Window/OSX/WindowImplCocoa.mm

@@ -370,15 +370,29 @@ void WindowImplCocoa::mouseMovedAt(int x, int y)
 }
 
 ////////////////////////////////////////////////////////////
-void WindowImplCocoa::mouseWheelScrolledAt(float delta, int x, int y)
+void WindowImplCocoa::mouseWheelScrolledAt(float deltaX, float deltaY, int x, int y)
 {
     Event event;
+
     event.type = Event::MouseWheelMoved;
-    event.mouseWheel.delta = delta;
+    event.mouseWheel.delta = deltaY;
     event.mouseWheel.x = x;
     event.mouseWheel.y = y;
     scaleOutXY(event.mouseWheel, m_delegate);
+    pushEvent(event);
 
+    event.type = Event::MouseWheelVerticalMoved;
+    event.mouseWheelVertical.delta = deltaY;
+    event.mouseWheelVertical.x = x;
+    event.mouseWheelVertical.y = y;
+    scaleOutXY(event.mouseWheelVertical, m_delegate);
+    pushEvent(event);
+
+    event.type = Event::MouseWheelHorizontalMoved;
+    event.mouseWheelHorizontal.delta = deltaX;
+    event.mouseWheelHorizontal.x = x;
+    event.mouseWheelHorizontal.y = y;
+    scaleOutXY(event.mouseWheelHorizontal, m_delegate);
     pushEvent(event);
 }
 

src/SFML/Window/Unix/WindowImplX11.cpp

@@ -1154,6 +1154,7 @@ bool WindowImplX11::processEvent(xcb_generic_event_t* windowEvent)
             xcb_button_press_event_t* e = reinterpret_cast<xcb_button_press_event_t*>(windowEvent);
 
             // XXX: Why button 8 and 9?
+            // Because 4 and 5 are the vertical wheel and 6 and 7 are horizontal wheel ;)
             xcb_button_t button = e->detail;
             if ((button == XCB_BUTTON_INDEX_1) ||
                 (button == XCB_BUTTON_INDEX_2) ||
@@ -1207,11 +1208,27 @@ bool WindowImplX11::processEvent(xcb_generic_event_t* windowEvent)
             else if ((button == XCB_BUTTON_INDEX_4) || (button == XCB_BUTTON_INDEX_5))
             {
                 Event event;
+
                 event.type             = Event::MouseWheelMoved;
                 event.mouseWheel.delta = button == XCB_BUTTON_INDEX_4 ? 1 : -1;
                 event.mouseWheel.x     = e->event_x;
                 event.mouseWheel.y     = e->event_y;
                 pushEvent(event);
+
+                event.type                     = Event::MouseWheelVerticalMoved;
+                event.mouseWheelVertical.delta = button == XCB_BUTTON_INDEX_4 ? 1 : -1;
+                event.mouseWheelVertical.x     = e->event_x;
+                event.mouseWheelVertical.y     = e->event_y;
+                pushEvent(event);
+            }
+            else if ((button == 6) || (button == 7))
+            {
+                Event event;
+                event.type                       = Event::MouseWheelHorizontalMoved;
+                event.mouseWheelHorizontal.delta = button == 6 ? 1 : -1;
+                event.mouseWheelHorizontal.x     = e->event_x;
+                event.mouseWheelHorizontal.y     = e->event_y;
+                pushEvent(event);
             }
             break;
         }

src/SFML/Window/Win32/WindowImplWin32.cpp

@@ -48,6 +48,9 @@
 #ifndef XBUTTON2
     #define XBUTTON2 0x0002
 #endif
+#ifndef WM_MOUSEHWHEEL
+    #define WM_MOUSEHWHEEL 0x020E
+#endif
 #ifndef MAPVK_VK_TO_VSC
     #define MAPVK_VK_TO_VSC (0)
 #endif
@@ -671,12 +674,42 @@ void WindowImplWin32::processEvent(UINT message, WPARAM wParam, LPARAM lParam)
             position.y = static_cast<Int16>(HIWORD(lParam));
             ScreenToClient(m_handle, &position);
 
+            Int16 delta = static_cast<Int16>(HIWORD(wParam));
+
             Event event;
+
             event.type             = Event::MouseWheelMoved;
-            event.mouseWheel.delta = static_cast<Int16>(HIWORD(wParam)) / 120;
+            event.mouseWheel.delta = delta / 120;
             event.mouseWheel.x     = position.x;
             event.mouseWheel.y     = position.y;
             pushEvent(event);
+
+            event.type                     = Event::MouseWheelVerticalMoved;
+            event.mouseWheelVertical.delta = static_cast<float>(delta) / 120.f;
+            event.mouseWheelVertical.x     = position.x;
+            event.mouseWheelVertical.y     = position.y;
+            pushEvent(event);
+
+            break;
+        }
+
+        // Mouse wheel event
+        case WM_MOUSEHWHEEL:
+        {
+            // Mouse position is in screen coordinates, convert it to window coordinates
+            POINT position;
+            position.x = static_cast<Int16>(LOWORD(lParam));
+            position.y = static_cast<Int16>(HIWORD(lParam));
+            ScreenToClient(m_handle, &position);
+
+            Int16 delta = static_cast<Int16>(HIWORD(wParam));
+
+            Event event;
+            event.type                       = Event::MouseWheelHorizontalMoved;
+            event.mouseWheelHorizontal.delta = -static_cast<float>(delta) / 120.f;
+            event.mouseWheelHorizontal.x     = position.x;
+            event.mouseWheelHorizontal.y     = position.y;
+            pushEvent(event);
             break;
         }