SDL_timer.h
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/*
Simple DirectMedia Layer
Copyright (C) 1997-2016 Sam Lantinga <slouken@libsdl.org>
This software is provided 'as-is', without any express or implied
warranty. In no event will the authors be held liable for any damages
arising from the use of this software.
Permission is granted to anyone to use this software for any purpose,
including commercial applications, and to alter it and redistribute it
freely, subject to the following restrictions:
1. The origin of this software must not be misrepresented; you must not
claim that you wrote the original software. If you use this software
in a product, an acknowledgment in the product documentation would be
appreciated but is not required.
2. Altered source versions must be plainly marked as such, and must not be
misrepresented as being the original software.
3. This notice may not be removed or altered from any source distribution.
*/
#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
/**
* \brief Get the number of milliseconds since the SDL library initialization.
*
* \note This value wraps if the program runs for more than ~49 days.
*/
extern DECLSPEC Uint32 SDLCALL SDL_GetTicks(void);
/**
* \brief Compare SDL ticks values, and return true if A has passed B
*
* e.g. if you want to wait 100 ms, you could do this:
* Uint32 timeout = SDL_GetTicks() + 100;
* while (!SDL_TICKS_PASSED(SDL_GetTicks(), timeout)) {
* ... do work until timeout has elapsed
* }
*/
#define SDL_TICKS_PASSED(A, B) ((Sint32)((B) - (A)) <= 0)
/**
* \brief Get the current value of the high resolution counter
*/
extern DECLSPEC Uint64 SDLCALL SDL_GetPerformanceCounter(void);
/**
* \brief Get the count per second of the high resolution counter
*/
extern DECLSPEC Uint64 SDLCALL SDL_GetPerformanceFrequency(void);
/**
* \brief Wait a specified number of milliseconds before returning.
*/
extern DECLSPEC void SDLCALL SDL_Delay(Uint32 ms);
/**
* Function prototype for the 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_TimerCallback) (Uint32 interval, void *param);
/**
* Definition of the timer ID type.
*/
typedef int SDL_TimerID;
/**
* \brief Add a new timer to the pool of timers already running.
*
* \return A timer ID, or 0 when an error occurs.
*/
extern DECLSPEC SDL_TimerID SDLCALL SDL_AddTimer(Uint32 interval,
SDL_TimerCallback callback,
void *param);
/**
* \brief Remove a timer knowing its ID.
*
* \return A boolean value indicating success or failure.
*
* \warning It is not safe to remove a timer multiple times.
*/
extern DECLSPEC SDL_bool SDLCALL SDL_RemoveTimer(SDL_TimerID id);
/* Ends C function definitions when using C++ */
#ifdef __cplusplus
}
#endif
#include "close_code.h"
#endif /* _SDL_timer_h */
/* vi: set ts=4 sw=4 expandtab: */
SDL_AddTimer
SDL_TimerID SDL_AddTimer(Uint32 interval, SDL_TimerCallback callback, void *param)
Add a new timer to the pool of timers already running.
Definition: SDL_timer.c:288
Uint32
uint32_t Uint32
An unsigned 32-bit integer type.
Definition: SDL_stdinc.h:155
SDL_TimerCallback
Uint32(* SDL_TimerCallback)(Uint32 interval, void *param)
Definition: SDL_timer.h:81
SDL_GetPerformanceFrequency
Uint64 SDL_GetPerformanceFrequency(void)
Get the count per second of the high resolution counter.
begin_code.h
Uint64
uint64_t Uint64
An unsigned 64-bit integer type.
Definition: SDL_stdinc.h:164
param
GLfloat param
Definition: SDL_opengl_glext.h:370
SDL_bool
SDL_bool
Definition: SDL_stdinc.h:126
DECLSPEC
#define DECLSPEC
Definition: SDL_internal.h:30
close_code.h
SDL_GetTicks
Uint32 SDL_GetTicks(void)
Get the number of milliseconds since the SDL library initialization.
callback
static Uint32 callback(Uint32 interval, void *param)
Definition: testtimer.c:34
SDL_stdinc.h
SDL_RemoveTimer
SDL_bool SDL_RemoveTimer(SDL_TimerID id)
Remove a timer knowing its ID.
Definition: SDL_timer.c:358
SDL_Delay
void SDL_Delay(Uint32 ms)
Wait a specified number of milliseconds before returning.
SDLCALL
#define SDLCALL
Definition: SDL_internal.h:31
SDL_error.h
SDL_GetPerformanceCounter
Uint64 SDL_GetPerformanceCounter(void)
Get the current value of the high resolution counter.
SDL_TimerID
int SDL_TimerID
Definition: SDL_timer.h:86