| .TH "SDL_SetTimer" "3" "Tue 11 Sep 2001, 23:01" "SDL" "SDL API Reference" |
| .SH "NAME" |
| SDL_SetTimer \- Set a callback to run after the specified number of milliseconds has elapsed\&. |
| .SH "SYNOPSIS" |
| .PP |
| \fB#include "SDL\&.h" |
| .sp |
| \fBint \fBSDL_SetTimer\fP\fR(\fBUint32 interval, SDL_TimerCallback callback\fR); |
| .SH "CALLBACK" |
| .PP |
| /* Function prototype for the timer callback function */ typedef Uint32 (*SDL_TimerCallback)(Uint32 interval); |
| .SH "DESCRIPTION" |
| .PP |
| Set a callback to run after the specified number of milliseconds has elapsed\&. The callback function is passed the current timer interval and returns the next timer interval\&. If the returned value is the same as the one passed in, the periodic alarm continues, otherwise a new alarm is scheduled\&. |
| .PP |
| To cancel a currently running timer, call \fBSDL_SetTimer(0, NULL);\fP |
| .PP |
| The timer callback function may run in a different thread than your main constant, and so shouldn\&'t call any functions from within itself\&. |
| .PP |
| The maximum resolution of this timer is 10 ms, which means that if you request a 16 ms timer, your callback will run approximately 20 ms later on an unloaded system\&. If you wanted to set a flag signaling a frame update at 30 frames per second (every 33 ms), you might set a timer for 30 ms (see example below)\&. |
| .PP |
| If you use this function, you need to pass \fBSDL_INIT_TIMER\fP to \fBSDL_Init()\fP\&. |
| .PP |
| .RS |
| \fBNote: |
| .PP |
| This function is kept for compatibility but has been superseded by the new timer functions \fISDL_AddTimer\fR and \fISDL_RemoveTimer\fR which support multiple timers\&. |
| .RE |
| .SH "EXAMPLES" |
| .PP |
| .PP |
| .nf |
| \f(CWSDL_SetTimer((33/10)*10, my_callback);\fR |
| .fi |
| .PP |
| .SH "SEE ALSO" |
| .PP |
| \fI\fBSDL_AddTimer\fP\fR |
| .\" created by instant / docbook-to-man, Tue 11 Sep 2001, 23:01 |
