Fixed bug 731 - No mechanism to extract the NSView for 3d library

include/SDL_syswm.h

@@ -82,6 +82,7 @@ struct SDL_SysWMinfo;
 #include <Cocoa/Cocoa.h>
 #else
 typedef struct _NSWindow NSWindow;
+typedef struct _NSView NSView;
 #endif
 #endif
 
@@ -187,6 +188,7 @@ struct SDL_SysWMinfo
         struct
         {
             NSWindow *window;           /* The Cocoa window */
+            NSView *view;               /* The Cocoa view */
         } cocoa;
 #endif
 #if defined(SDL_VIDEO_DRIVER_UIKIT)

src/video/cocoa/SDL_cocoawindow.m

@@ -1131,6 +1131,7 @@ Cocoa_GetWindowWMInfo(_THIS, SDL_Window * window, SDL_SysWMinfo * info)
     if (info->version.major <= SDL_MAJOR_VERSION) {
         info->subsystem = SDL_SYSWM_COCOA;
         info->info.cocoa.window = nswindow;
+        info->info.cocoa.view = [nswindow contentView];
         return SDL_TRUE;
     } else {
         SDL_SetError("Application not compiled with SDL %d.%d\n",