* no need to deal with EventObject, that kind of functionality is handled
  internally

* PG_TimerObject should be a mixin
  - or perhaps use a different SDL library?
* PG_Navigator as well, but what is it?
  - it makes the cursor jump

* How in the world are we going to bridge RUDL and Paragui?
  - the SDL_Surface objects need to be shared
  - also, the clipping rect if any
  - Idea: typemap to convert SDL_Surface to unsigned long (out)
  - Idea: typemap to convert unsigned long *sdl_surface_ptr to SDL_Surface (in)