[SDL] Collecting the keypresses without the mouse events?

[Peter Mulholland]

Hello Matt,

Sunday, March 12, 2006, 9:36:47 PM, you wrote:

MK> Hi!

MK> How to collect all the pending keypresses and avoiding to 
MK> have to discard all the mouse events? This is needed 
MK> in any FPS game (DooM, Quake etc..) where the user uses 
MK> both the keyboard and the mouse at the same time.

<snip>

MK> The above code makes the while() stuck as long as the user 
MK> keeps moving the mouse thus introducing a jerky movement in 
MK> the game - That's one of the reasons why Icculus' port of Duke 
MK> Nukem 3d has a Jerky mouse behavior.

MK> So I tryed to use a 

MK> SDL_PumpEvents(); 
MK> SDL_GetMouseState(...);

MK> before doing a 

MK> while (SDL_PollEvent(&event)) 
MK>    root_sdl_event_filter(&event); 

MK> because only the mouse position at the time we probe 
MK> is actually needed for FPS games. But SDL_GetMouseState 
MK> doesn't seem to remove the move mouse events at all, so 
MK> it's pointless and the while(...) will remain very laggy.

I also had this issue. I solved it by telling SDL to ignore mouse
movement events:

SDL_EventState(SDL_MOUSEMOTION, SDL_IGNORE);

Then I polled for mouse movement per frame with SDL_GetMouseState()

For an FPS you might be best reading key input this way too, since as
multiple keypresses will no doubt be needed. It would be far more
efficient to dump keystate into an array and check buttons in there
than process messages.

-- 
Best regards,
 Peter                            mailto:darkmatter at freeuk.com