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1 | .TH "SDL_SetTimer" "3" "Tue 11 Sep 2001, 23:01" "SDL" "SDL API Reference" |
2 | .SH "NAME" |
3 | SDL_SetTimer \- Set a callback to run after the specified number of milliseconds has elapsed\&. |
4 | .SH "SYNOPSIS" |
5 | .PP |
6 | \fB#include "SDL\&.h" |
7 | .sp |
8 | \fBint \fBSDL_SetTimer\fP\fR(\fBUint32 interval, SDL_TimerCallback callback\fR); |
9 | .SH "CALLBACK" |
10 | .PP |
11 | /* Function prototype for the timer callback function */ typedef Uint32 (*SDL_TimerCallback)(Uint32 interval); |
12 | .SH "DESCRIPTION" |
13 | .PP |
14 | 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\&. |
15 | .PP |
16 | To cancel a currently running timer, call \fBSDL_SetTimer(0, NULL);\fP |
17 | .PP |
18 | The timer callback function may run in a different thread than your main constant, and so shouldn\&'t call any functions from within itself\&. |
19 | .PP |
20 | 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)\&. |
21 | .PP |
22 | If you use this function, you need to pass \fBSDL_INIT_TIMER\fP to \fBSDL_Init()\fP\&. |
23 | .PP |
24 | .RS |
25 | \fBNote: |
26 | .PP |
27 | This function is kept for compatibility but has been superseded by the new timer functions \fISDL_AddTimer\fR and \fISDL_RemoveTimer\fR which support multiple timers\&. |
28 | .RE |
29 | .SH "EXAMPLES" |
30 | .PP |
31 | .PP |
32 | .nf |
33 | \f(CWSDL_SetTimer((33/10)*10, my_callback);\fR |
34 | .fi |
35 | .PP |
36 | .SH "SEE ALSO" |
37 | .PP |
38 | \fI\fBSDL_AddTimer\fP\fR |
39 | .\" created by instant / docbook-to-man, Tue 11 Sep 2001, 23:01 |