plucky (3) SDL_SetEventFilter.3.gz

NAME

       SDL_SetEventFilter  -  Set  up a filter to process all events before they are added to the internal event
       queue.

HEADER FILE

       Defined in SDL3/SDL_events.h

SYNOPSIS

       #include "SDL3/SDL.h"

       void SDL_SetEventFilter(SDL_EventFilter filter, void *userdata);

DESCRIPTION

       If you just want to see events without modifying them or preventing them from being  queued,  you  should
       use SDL_AddEventWatch () instead.

       If  the  filter function returns true when called, then the event will be added to the internal queue. If
       it returns false, then the event will be dropped from the queue, but the internal  state  will  still  be
       updated.  This  allows  selective filtering of dynamically arriving events.  WARNING : Be very careful of
       what you do in the event filter function, as it may run in a different thread!

       On platforms that support it, if the quit event is generated by an interrupt signal (e.g. pressing  Ctrl-
       C), it will be delivered to the application at the next event poll.

       Note: Disabled events never make it to the event filter function; see

       SDL_SetEventEnabled ().

       Note:  Events pushed onto the queue with SDL_PushEvent () get passed through the event filter, but events
       pushed onto the queue with

       SDL_PeepEvents () do not.

FUNCTION PARAMETERS

       filter an SDL_EventFilter
               function to call when an event happens.

       userdata
              a pointer that is passed to filter .

THREAD SAFETY

       It is safe to call this function from any thread.

AVAILABILITY

       This function is available since SDL 3.2.0.

SEE ALSO

       •(3),   SDL_AddEventWatch(3),   •(3),   SDL_SetEventEnabled(3),   •(3),   SDL_GetEventFilter(3),    •(3),
       SDL_PeepEvents(3), •(3), SDL_PushEvent(3)