Added support for double-clicks, through a new "clicks" field in the mouse button event.

include/SDL_events.h

@@ -239,8 +239,8 @@ typedef struct SDL_MouseButtonEvent
     Uint32 which;       /**< The mouse instance id, or SDL_TOUCH_MOUSEID */
     Uint8 button;       /**< The mouse button index */
     Uint8 state;        /**< ::SDL_PRESSED or ::SDL_RELEASED */
+    Uint8 clicks;       /**< 1 for single-click, 2 for double-click, etc. */
     Uint8 padding1;
-    Uint8 padding2;
     Sint32 x;           /**< X coordinate, relative to window */
     Sint32 y;           /**< Y coordinate, relative to window */
 } SDL_MouseButtonEvent;