Fixed bug #382

Added horizontal scrolling support

--HG--
extra : convert_revision : svn%3Ac70aab31-4412-0410-b14c-859654838e24/trunk%402428

include/SDL_events.h

@@ -199,7 +199,8 @@ typedef struct SDL_MouseWheelEvent
 {
     Uint8 type;             /**< SDL_MOUSEWHEEL */
     Uint8 which;            /**< The mouse device index */
-    int motion;             /**< The direction and distance scrolled */
+    int x;                  /**< The amount scrolled horizontally */
+    int y;                  /**< The amount scrolled vertically */
     SDL_WindowID windowID;  /**< The window with mouse focus, if any */
 } SDL_MouseWheelEvent;