2
SDL - Simple DirectMedia Layer
3
Copyright (C) 1997-2004 Sam Lantinga
5
This library is free software; you can redistribute it and/or
6
modify it under the terms of the GNU Library General Public
7
License as published by the Free Software Foundation; either
8
version 2 of the License, or (at your option) any later version.
10
This library is distributed in the hope that it will be useful,
11
but WITHOUT ANY WARRANTY; without even the implied warranty of
12
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13
Library General Public License for more details.
15
You should have received a copy of the GNU Library General Public
16
License along with this library; if not, write to the Free
17
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
25
"@(#) $Id: SDL_timer.h,v 1.7 2005/01/13 23:24:56 slouken Exp $";
31
/* Header for the SDL time management routines */
34
#include "SDL_types.h"
36
#include "begin_code.h"
37
/* Set up for C function definitions, even when using C++ */
42
/* This is the OS scheduler timeslice, in milliseconds */
43
#define SDL_TIMESLICE 10
45
/* This is the maximum resolution of the SDL timer on all platforms */
46
#define TIMER_RESOLUTION 10 /* Experimentally determined */
48
/* Get the number of milliseconds since the SDL library initialization.
49
* Note that this value wraps if the program runs for more than ~49 days.
51
extern DECLSPEC Uint32 SDLCALL SDL_GetTicks(void);
53
/* Wait a specified number of milliseconds before returning */
54
extern DECLSPEC void SDLCALL SDL_Delay(Uint32 ms);
56
/* Function prototype for the timer callback function */
57
typedef Uint32 (SDLCALL *SDL_TimerCallback)(Uint32 interval);
59
/* Set a callback to run after the specified number of milliseconds has
60
* elapsed. The callback function is passed the current timer interval
61
* and returns the next timer interval. If the returned value is the
62
* same as the one passed in, the periodic alarm continues, otherwise a
63
* new alarm is scheduled. If the callback returns 0, the periodic alarm
66
* To cancel a currently running timer, call SDL_SetTimer(0, NULL);
68
* The timer callback function may run in a different thread than your
69
* main code, and so shouldn't call any functions from within itself.
71
* The maximum resolution of this timer is 10 ms, which means that if
72
* you request a 16 ms timer, your callback will run approximately 20 ms
73
* later on an unloaded system. If you wanted to set a flag signaling
74
* a frame update at 30 frames per second (every 33 ms), you might set a
76
* SDL_SetTimer((33/10)*10, flag_update);
78
* If you use this function, you need to pass SDL_INIT_TIMER to SDL_Init().
80
* Under UNIX, you should not use raise or use SIGALRM and this function
81
* in the same program, as it is implemented using setitimer(). You also
82
* should not use this function in multi-threaded applications as signals
83
* to multi-threaded apps have undefined behavior in some implementations.
85
* This function returns 0 if successful, or -1 if there was an error.
87
extern DECLSPEC int SDLCALL SDL_SetTimer(Uint32 interval, SDL_TimerCallback callback);
89
/* New timer API, supports multiple timers
90
* Written by Stephane Peter <megastep@lokigames.com>
93
/* Function prototype for the new timer callback function.
94
* The callback function is passed the current timer interval and returns
95
* the next timer interval. If the returned value is the same as the one
96
* passed in, the periodic alarm continues, otherwise a new alarm is
97
* scheduled. If the callback returns 0, the periodic alarm is cancelled.
99
typedef Uint32 (SDLCALL *SDL_NewTimerCallback)(Uint32 interval, void *param);
101
/* Definition of the timer ID type */
102
typedef struct _SDL_TimerID *SDL_TimerID;
104
/* Add a new timer to the pool of timers already running.
105
Returns a timer ID, or NULL when an error occurs.
107
extern DECLSPEC SDL_TimerID SDLCALL SDL_AddTimer(Uint32 interval, SDL_NewTimerCallback callback, void *param);
109
/* Remove one of the multiple timers knowing its ID.
110
* Returns a boolean value indicating success.
112
extern DECLSPEC SDL_bool SDLCALL SDL_RemoveTimer(SDL_TimerID t);
114
/* Ends C function definitions when using C++ */
118
#include "close_code.h"
120
#endif /* _SDL_timer_h */
added
removed
code/SDL12/include/SDL_timer.h
