| 1 | /* |
| 2 | SDL - Simple DirectMedia Layer |
| 3 | Copyright (C) 1997-2009 Sam Lantinga |
| 4 | |
| 5 | This library is free software; you can redistribute it and/or |
| 6 | modify it under the terms of the GNU Lesser General Public |
| 7 | License as published by the Free Software Foundation; either |
| 8 | version 2.1 of the License, or (at your option) any later version. |
| 9 | |
| 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 | Lesser General Public License for more details. |
| 14 | |
| 15 | You should have received a copy of the GNU Lesser General Public |
| 16 | License along with this library; if not, write to the Free Software |
| 17 | Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA |
| 18 | |
| 19 | Sam Lantinga |
| 20 | slouken@libsdl.org |
| 21 | */ |
| 22 | #include "SDL_config.h" |
| 23 | |
| 24 | #ifdef SDL_TIMER_WIN32 |
| 25 | |
| 26 | #define WIN32_LEAN_AND_MEAN |
| 27 | #include <windows.h> |
| 28 | #include <mmsystem.h> |
| 29 | |
| 30 | #include "SDL_timer.h" |
| 31 | #include "../SDL_timer_c.h" |
| 32 | |
| 33 | #ifdef _WIN32_WCE |
| 34 | #error This is WinCE. Please use src/timer/wince/SDL_systimer.c instead. |
| 35 | #endif |
| 36 | |
| 37 | #define TIME_WRAP_VALUE (~(DWORD)0) |
| 38 | |
| 39 | /* The first (low-resolution) ticks value of the application */ |
| 40 | static DWORD start; |
| 41 | |
| 42 | #ifndef USE_GETTICKCOUNT |
| 43 | /* Store if a high-resolution performance counter exists on the system */ |
| 44 | static BOOL hires_timer_available; |
| 45 | /* The first high-resolution ticks value of the application */ |
| 46 | static LARGE_INTEGER hires_start_ticks; |
| 47 | /* The number of ticks per second of the high-resolution performance counter */ |
| 48 | static LARGE_INTEGER hires_ticks_per_second; |
| 49 | #endif |
| 50 | |
| 51 | void SDL_StartTicks(void) |
| 52 | { |
| 53 | /* Set first ticks value */ |
| 54 | #ifdef USE_GETTICKCOUNT |
| 55 | start = GetTickCount(); |
| 56 | #else |
| 57 | #if 0 /* Apparently there are problems with QPC on Win2K */ |
| 58 | if (QueryPerformanceFrequency(&hires_ticks_per_second) == TRUE) |
| 59 | { |
| 60 | hires_timer_available = TRUE; |
| 61 | QueryPerformanceCounter(&hires_start_ticks); |
| 62 | } |
| 63 | else |
| 64 | #endif |
| 65 | { |
| 66 | hires_timer_available = FALSE; |
| 67 | timeBeginPeriod(1); /* use 1 ms timer precision */ |
| 68 | start = timeGetTime(); |
| 69 | } |
| 70 | #endif |
| 71 | } |
| 72 | |
| 73 | Uint32 SDL_GetTicks(void) |
| 74 | { |
| 75 | DWORD now, ticks; |
| 76 | #ifndef USE_GETTICKCOUNT |
| 77 | LARGE_INTEGER hires_now; |
| 78 | #endif |
| 79 | |
| 80 | #ifdef USE_GETTICKCOUNT |
| 81 | now = GetTickCount(); |
| 82 | #else |
| 83 | if (hires_timer_available) |
| 84 | { |
| 85 | QueryPerformanceCounter(&hires_now); |
| 86 | |
| 87 | hires_now.QuadPart -= hires_start_ticks.QuadPart; |
| 88 | hires_now.QuadPart *= 1000; |
| 89 | hires_now.QuadPart /= hires_ticks_per_second.QuadPart; |
| 90 | |
| 91 | return (DWORD)hires_now.QuadPart; |
| 92 | } |
| 93 | else |
| 94 | { |
| 95 | now = timeGetTime(); |
| 96 | } |
| 97 | #endif |
| 98 | |
| 99 | if ( now < start ) { |
| 100 | ticks = (TIME_WRAP_VALUE-start) + now; |
| 101 | } else { |
| 102 | ticks = (now - start); |
| 103 | } |
| 104 | return(ticks); |
| 105 | } |
| 106 | |
| 107 | void SDL_Delay(Uint32 ms) |
| 108 | { |
| 109 | Sleep(ms); |
| 110 | } |
| 111 | |
| 112 | /* Data to handle a single periodic alarm */ |
| 113 | static UINT timerID = 0; |
| 114 | |
| 115 | static void CALLBACK HandleAlarm(UINT uID, UINT uMsg, DWORD_PTR dwUser, |
| 116 | DWORD_PTR dw1, DWORD_PTR dw2) |
| 117 | { |
| 118 | SDL_ThreadedTimerCheck(); |
| 119 | } |
| 120 | |
| 121 | |
| 122 | int SDL_SYS_TimerInit(void) |
| 123 | { |
| 124 | MMRESULT result; |
| 125 | |
| 126 | /* Set timer resolution */ |
| 127 | result = timeBeginPeriod(TIMER_RESOLUTION); |
| 128 | if ( result != TIMERR_NOERROR ) { |
| 129 | SDL_SetError("Warning: Can't set %d ms timer resolution", |
| 130 | TIMER_RESOLUTION); |
| 131 | } |
| 132 | /* Allow 10 ms of drift so we don't chew on CPU */ |
| 133 | timerID = timeSetEvent(TIMER_RESOLUTION,1,HandleAlarm,0,TIME_PERIODIC); |
| 134 | if ( ! timerID ) { |
| 135 | SDL_SetError("timeSetEvent() failed"); |
| 136 | return(-1); |
| 137 | } |
| 138 | return(SDL_SetTimerThreaded(1)); |
| 139 | } |
| 140 | |
| 141 | void SDL_SYS_TimerQuit(void) |
| 142 | { |
| 143 | if ( timerID ) { |
| 144 | timeKillEvent(timerID); |
| 145 | } |
| 146 | timeEndPeriod(TIMER_RESOLUTION); |
| 147 | } |
| 148 | |
| 149 | int SDL_SYS_StartTimer(void) |
| 150 | { |
| 151 | SDL_SetError("Internal logic error: Win32 uses threaded timer"); |
| 152 | return(-1); |
| 153 | } |
| 154 | |
| 155 | void SDL_SYS_StopTimer(void) |
| 156 | { |
| 157 | return; |
| 158 | } |
| 159 | |
| 160 | #endif /* SDL_TIMER_WIN32 */ |