| /* |
| Simple DirectMedia Layer |
| Copyright (C) 1997-2017 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. |
| */ |
| #include "../../SDL_internal.h" |
| |
| #ifdef SDL_TIMER_WINDOWS |
| |
| #include "../../core/windows/SDL_windows.h" |
| #include <mmsystem.h> |
| |
| #include "SDL_timer.h" |
| #include "SDL_hints.h" |
| |
| |
| /* The first (low-resolution) ticks value of the application */ |
| static DWORD start = 0; |
| static BOOL ticks_started = FALSE; |
| |
| /* 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; |
| |
| static void |
| SDL_SetSystemTimerResolution(const UINT uPeriod) |
| { |
| #ifndef __WINRT__ |
| static UINT timer_period = 0; |
| |
| if (uPeriod != timer_period) { |
| if (timer_period) { |
| timeEndPeriod(timer_period); |
| } |
| |
| timer_period = uPeriod; |
| |
| if (timer_period) { |
| timeBeginPeriod(timer_period); |
| } |
| } |
| #endif |
| } |
| |
| static void SDLCALL |
| SDL_TimerResolutionChanged(void *userdata, const char *name, const char *oldValue, const char *hint) |
| { |
| UINT uPeriod; |
| |
| /* Unless the hint says otherwise, let's have good sleep precision */ |
| if (hint && *hint) { |
| uPeriod = SDL_atoi(hint); |
| } else { |
| uPeriod = 1; |
| } |
| if (uPeriod || oldValue != hint) { |
| SDL_SetSystemTimerResolution(uPeriod); |
| } |
| } |
| |
| void |
| SDL_TicksInit(void) |
| { |
| if (ticks_started) { |
| return; |
| } |
| ticks_started = SDL_TRUE; |
| |
| /* if we didn't set a precision, set it high. This affects lots of things |
| on Windows besides the SDL timers, like audio callbacks, etc. */ |
| SDL_AddHintCallback(SDL_HINT_TIMER_RESOLUTION, |
| SDL_TimerResolutionChanged, NULL); |
| |
| /* Set first ticks value */ |
| /* QueryPerformanceCounter has had problems in the past, but lots of games |
| use it, so we'll rely on it here. |
| */ |
| if (QueryPerformanceFrequency(&hires_ticks_per_second) == TRUE) { |
| hires_timer_available = TRUE; |
| QueryPerformanceCounter(&hires_start_ticks); |
| } else { |
| hires_timer_available = FALSE; |
| #ifndef __WINRT__ |
| start = timeGetTime(); |
| #endif /* __WINRT__ */ |
| } |
| } |
| |
| void |
| SDL_TicksQuit(void) |
| { |
| SDL_DelHintCallback(SDL_HINT_TIMER_RESOLUTION, |
| SDL_TimerResolutionChanged, NULL); |
| |
| SDL_SetSystemTimerResolution(0); /* always release our timer resolution request. */ |
| |
| start = 0; |
| ticks_started = SDL_FALSE; |
| } |
| |
| Uint32 |
| SDL_GetTicks(void) |
| { |
| DWORD now = 0; |
| LARGE_INTEGER hires_now; |
| |
| if (!ticks_started) { |
| SDL_TicksInit(); |
| } |
| |
| 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 { |
| #ifndef __WINRT__ |
| now = timeGetTime(); |
| #endif /* __WINRT__ */ |
| } |
| |
| return (now - start); |
| } |
| |
| Uint64 |
| SDL_GetPerformanceCounter(void) |
| { |
| LARGE_INTEGER counter; |
| |
| if (!QueryPerformanceCounter(&counter)) { |
| return SDL_GetTicks(); |
| } |
| return counter.QuadPart; |
| } |
| |
| Uint64 |
| SDL_GetPerformanceFrequency(void) |
| { |
| LARGE_INTEGER frequency; |
| |
| if (!QueryPerformanceFrequency(&frequency)) { |
| return 1000; |
| } |
| return frequency.QuadPart; |
| } |
| |
| void |
| SDL_Delay(Uint32 ms) |
| { |
| /* Sleep() is not publicly available to apps in early versions of WinRT. |
| * |
| * Visual C++ 2013 Update 4 re-introduced Sleep() for Windows 8.1 and |
| * Windows Phone 8.1. |
| * |
| * Use the compiler version to determine availability. |
| * |
| * NOTE #1: _MSC_FULL_VER == 180030723 for Visual C++ 2013 Update 3. |
| * NOTE #2: Visual C++ 2013, when compiling for Windows 8.0 and |
| * Windows Phone 8.0, uses the Visual C++ 2012 compiler to build |
| * apps and libraries. |
| */ |
| #if defined(__WINRT__) && defined(_MSC_FULL_VER) && (_MSC_FULL_VER <= 180030723) |
| static HANDLE mutex = 0; |
| if (!mutex) { |
| mutex = CreateEventEx(0, 0, 0, EVENT_ALL_ACCESS); |
| } |
| WaitForSingleObjectEx(mutex, ms, FALSE); |
| #else |
| if (!ticks_started) { |
| SDL_TicksInit(); |
| } |
| |
| Sleep(ms); |
| #endif |
| } |
| |
| #endif /* SDL_TIMER_WINDOWS */ |
| |
| /* vi: set ts=4 sw=4 expandtab: */ |