[SDL] Detecting scroll wheel up (and down) in OS X?

[Sam Lantinga]

> Recently I've been trying to detect for scroll wheel movements in OS X 
> with:

> if(SDL_GetMouseState(NULL, NULL) & SDL_BUTTON(SDL_BUTTON_WHEELUP)) 

Since mouse wheel motion is an instantaneous event, you'll never see
the state on if you poll it.  To handle mouse wheel events, you actually
have to handle mouse button events and figure out how far you want to
move based on the number of events you get.

See ya,
	-Sam Lantinga, Software Engineer, Blizzard Entertainment