1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
|
/*
SDL - Simple DirectMedia Layer
Copyright (C) 1997-2012 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
*/
#include "SDL_config.h"
#ifdef SDL_TIMER_WIN32
#define WIN32_LEAN_AND_MEAN
#include <windows.h>
#include <mmsystem.h>
#include "SDL_timer.h"
#include "../SDL_timer_c.h"
#ifdef _WIN32_WCE
#error This is WinCE. Please use src/timer/wince/SDL_systimer.c instead.
#endif
#define TIME_WRAP_VALUE (~(DWORD)0)
/* The first (low-resolution) ticks value of the application */
static DWORD start;
#ifndef USE_GETTICKCOUNT
/* Store if a high-resolution performance counter exists on the system */
static BOOL hires_timer_available;
/* The first high-resolution ticks value of the application */
static LARGE_INTEGER hires_start_ticks;
/* The number of ticks per second of the high-resolution performance counter */
static LARGE_INTEGER hires_ticks_per_second;
#endif
void SDL_StartTicks(void)
{
/* Set first ticks value */
#ifdef USE_GETTICKCOUNT
start = GetTickCount();
#else
#if 0 /* Apparently there are problems with QPC on Win2K */
if (QueryPerformanceFrequency(&hires_ticks_per_second) == TRUE)
{
hires_timer_available = TRUE;
QueryPerformanceCounter(&hires_start_ticks);
}
else
#endif
{
hires_timer_available = FALSE;
timeBeginPeriod(1); /* use 1 ms timer precision */
start = timeGetTime();
}
#endif
}
Uint32 SDL_GetTicks(void)
{
DWORD now, ticks;
#ifndef USE_GETTICKCOUNT
LARGE_INTEGER hires_now;
#endif
#ifdef USE_GETTICKCOUNT
now = GetTickCount();
#else
if (hires_timer_available)
{
QueryPerformanceCounter(&hires_now);
hires_now.QuadPart -= hires_start_ticks.QuadPart;
hires_now.QuadPart *= 1000;
hires_now.QuadPart /= hires_ticks_per_second.QuadPart;
return (DWORD)hires_now.QuadPart;
}
else
{
now = timeGetTime();
}
#endif
if ( now < start ) {
ticks = (TIME_WRAP_VALUE-start) + now;
} else {
ticks = (now - start);
}
return(ticks);
}
void SDL_Delay(Uint32 ms)
{
Sleep(ms);
}
/* Data to handle a single periodic alarm */
static UINT timerID = 0;
static void CALLBACK HandleAlarm(UINT uID, UINT uMsg, DWORD_PTR dwUser,
DWORD_PTR dw1, DWORD_PTR dw2)
{
SDL_ThreadedTimerCheck();
}
int SDL_SYS_TimerInit(void)
{
MMRESULT result;
/* Set timer resolution */
result = timeBeginPeriod(TIMER_RESOLUTION);
if ( result != TIMERR_NOERROR ) {
SDL_SetError("Warning: Can't set %d ms timer resolution",
TIMER_RESOLUTION);
}
/* Allow 10 ms of drift so we don't chew on CPU */
timerID = timeSetEvent(TIMER_RESOLUTION,1,HandleAlarm,0,TIME_PERIODIC);
if ( ! timerID ) {
SDL_SetError("timeSetEvent() failed");
return(-1);
}
return(SDL_SetTimerThreaded(1));
}
void SDL_SYS_TimerQuit(void)
{
if ( timerID ) {
timeKillEvent(timerID);
}
timeEndPeriod(TIMER_RESOLUTION);
}
int SDL_SYS_StartTimer(void)
{
SDL_SetError("Internal logic error: Win32 uses threaded timer");
return(-1);
}
void SDL_SYS_StopTimer(void)
{
return;
}
#endif /* SDL_TIMER_WIN32 */
|
