126 lines
4.4 KiB
C
126 lines
4.4 KiB
C
/*
|
|
SDL - Simple DirectMedia Layer
|
|
Copyright (C) 1997-2009 Sam Lantinga
|
|
|
|
This library is free software; you can redistribute it and/or
|
|
modify it under the terms of the GNU Lesser General Public
|
|
License as published by the Free Software Foundation; either
|
|
version 2.1 of the License, or (at your option) any later version.
|
|
|
|
This library is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
Lesser General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Lesser General Public
|
|
License along with this library; if not, write to the Free Software
|
|
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
|
|
|
|
Sam Lantinga
|
|
slouken@libsdl.org
|
|
*/
|
|
|
|
#ifndef _SDL_timer_h
|
|
#define _SDL_timer_h
|
|
|
|
/** @file SDL_timer.h
|
|
* Header for the SDL time management routines
|
|
*/
|
|
|
|
#include "SDL_stdinc.h"
|
|
#include "SDL_error.h"
|
|
|
|
#include "begin_code.h"
|
|
/* Set up for C function definitions, even when using C++ */
|
|
#ifdef __cplusplus
|
|
extern "C" {
|
|
#endif
|
|
|
|
/** This is the OS scheduler timeslice, in milliseconds */
|
|
#define SDL_TIMESLICE 10
|
|
|
|
/** This is the maximum resolution of the SDL timer on all platforms */
|
|
#define TIMER_RESOLUTION 10 /**< Experimentally determined */
|
|
|
|
/**
|
|
* Get the number of milliseconds since the SDL library initialization.
|
|
* Note that this value wraps if the program runs for more than ~49 days.
|
|
*/
|
|
extern DECLSPEC Uint32 SDLCALL SDL_GetTicks(void);
|
|
|
|
/** Wait a specified number of milliseconds before returning */
|
|
extern DECLSPEC void SDLCALL SDL_Delay(Uint32 ms);
|
|
|
|
/** Function prototype for the timer callback function */
|
|
typedef Uint32 (SDLCALL *SDL_TimerCallback)(Uint32 interval);
|
|
|
|
/**
|
|
* 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. If the callback returns 0, the periodic alarm
|
|
* is cancelled.
|
|
*
|
|
* To cancel a currently running timer, call SDL_SetTimer(0, NULL);
|
|
*
|
|
* The timer callback function may run in a different thread than your
|
|
* main code, and so shouldn't call any functions from within itself.
|
|
*
|
|
* 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:
|
|
* @code SDL_SetTimer((33/10)*10, flag_update); @endcode
|
|
*
|
|
* If you use this function, you need to pass SDL_INIT_TIMER to SDL_Init().
|
|
*
|
|
* Under UNIX, you should not use raise or use SIGALRM and this function
|
|
* in the same program, as it is implemented using setitimer(). You also
|
|
* should not use this function in multi-threaded applications as signals
|
|
* to multi-threaded apps have undefined behavior in some implementations.
|
|
*
|
|
* This function returns 0 if successful, or -1 if there was an error.
|
|
*/
|
|
extern DECLSPEC int SDLCALL SDL_SetTimer(Uint32 interval, SDL_TimerCallback callback);
|
|
|
|
/** @name New timer API
|
|
* New timer API, supports multiple timers
|
|
* Written by Stephane Peter <megastep@lokigames.com>
|
|
*/
|
|
/*@{*/
|
|
|
|
/**
|
|
* Function prototype for the new timer callback function.
|
|
* 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. If the callback returns 0, the periodic alarm is cancelled.
|
|
*/
|
|
typedef Uint32 (SDLCALL *SDL_NewTimerCallback)(Uint32 interval, void *param);
|
|
|
|
/** Definition of the timer ID type */
|
|
typedef struct _SDL_TimerID *SDL_TimerID;
|
|
|
|
/** Add a new timer to the pool of timers already running.
|
|
* Returns a timer ID, or NULL when an error occurs.
|
|
*/
|
|
extern DECLSPEC SDL_TimerID SDLCALL SDL_AddTimer(Uint32 interval, SDL_NewTimerCallback callback, void *param);
|
|
|
|
/**
|
|
* Remove one of the multiple timers knowing its ID.
|
|
* Returns a boolean value indicating success.
|
|
*/
|
|
extern DECLSPEC SDL_bool SDLCALL SDL_RemoveTimer(SDL_TimerID t);
|
|
|
|
/*@}*/
|
|
|
|
/* Ends C function definitions when using C++ */
|
|
#ifdef __cplusplus
|
|
}
|
|
#endif
|
|
#include "close_code.h"
|
|
|
|
#endif /* _SDL_timer_h */
|