SDL 2.0
SDL_timer.h
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1/*
2 Simple DirectMedia Layer
3 Copyright (C) 1997-2019 Sam Lantinga <slouken@libsdl.org>
4
5 This software is provided 'as-is', without any express or implied
6 warranty. In no event will the authors be held liable for any damages
7 arising from the use of this software.
8
9 Permission is granted to anyone to use this software for any purpose,
10 including commercial applications, and to alter it and redistribute it
11 freely, subject to the following restrictions:
12
13 1. The origin of this software must not be misrepresented; you must not
14 claim that you wrote the original software. If you use this software
15 in a product, an acknowledgment in the product documentation would be
16 appreciated but is not required.
17 2. Altered source versions must be plainly marked as such, and must not be
18 misrepresented as being the original software.
19 3. This notice may not be removed or altered from any source distribution.
20*/
21
22#ifndef SDL_timer_h_
23#define SDL_timer_h_
24
25/**
26 * \file SDL_timer.h
27 *
28 * Header for the SDL time management routines.
29 */
30
31#include "SDL_stdinc.h"
32#include "SDL_error.h"
33
34#include "begin_code.h"
35/* Set up for C function definitions, even when using C++ */
36#ifdef __cplusplus
37extern "C" {
38#endif
39
40/**
41 * \brief Get the number of milliseconds since the SDL library initialization.
42 *
43 * \note This value wraps if the program runs for more than ~49 days.
44 */
46
47/**
48 * \brief Compare SDL ticks values, and return true if A has passed B
49 *
50 * e.g. if you want to wait 100 ms, you could do this:
51 * Uint32 timeout = SDL_GetTicks() + 100;
52 * while (!SDL_TICKS_PASSED(SDL_GetTicks(), timeout)) {
53 * ... do work until timeout has elapsed
54 * }
55 */
56#define SDL_TICKS_PASSED(A, B) ((Sint32)((B) - (A)) <= 0)
57
58/**
59 * \brief Get the current value of the high resolution counter
60 */
62
63/**
64 * \brief Get the count per second of the high resolution counter
65 */
67
68/**
69 * \brief Wait a specified number of milliseconds before returning.
70 */
72
73/**
74 * Function prototype for the timer callback function.
75 *
76 * The callback function is passed the current timer interval and returns
77 * the next timer interval. If the returned value is the same as the one
78 * passed in, the periodic alarm continues, otherwise a new alarm is
79 * scheduled. If the callback returns 0, the periodic alarm is cancelled.
80 */
81typedef Uint32 (SDLCALL * SDL_TimerCallback) (Uint32 interval, void *param);
82
83/**
84 * Definition of the timer ID type.
85 */
86typedef int SDL_TimerID;
87
88/**
89 * \brief Add a new timer to the pool of timers already running.
90 *
91 * \return A timer ID, or 0 when an error occurs.
92 */
95 void *param);
96
97/**
98 * \brief Remove a timer knowing its ID.
99 *
100 * \return A boolean value indicating success or failure.
101 *
102 * \warning It is not safe to remove a timer multiple times.
103 */
105
106
107/* Ends C function definitions when using C++ */
108#ifdef __cplusplus
109}
110#endif
111#include "close_code.h"
112
113#endif /* SDL_timer_h_ */
114
115/* vi: set ts=4 sw=4 expandtab: */
#define SDLCALL
Definition: SDL_internal.h:49
#define DECLSPEC
Definition: SDL_internal.h:48
GLfloat param
SDL_bool
Definition: SDL_stdinc.h:162
uint32_t Uint32
Definition: SDL_stdinc.h:203
uint64_t Uint64
Definition: SDL_stdinc.h:216
Uint32 SDL_GetTicks(void)
Get the number of milliseconds since the SDL library initialization.
Uint32(* SDL_TimerCallback)(Uint32 interval, void *param)
Definition: SDL_timer.h:81
SDL_bool SDL_RemoveTimer(SDL_TimerID id)
Remove a timer knowing its ID.
Definition: SDL_timer.c:342
Uint64 SDL_GetPerformanceFrequency(void)
Get the count per second of the high resolution counter.
Uint64 SDL_GetPerformanceCounter(void)
Get the current value of the high resolution counter.
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:279
void SDL_Delay(Uint32 ms)
Wait a specified number of milliseconds before returning.
int SDL_TimerID
Definition: SDL_timer.h:86
static Uint32 callback(Uint32 interval, void *param)
Definition: testtimer.c:34