/*

    SDL - Simple DirectMedia Layer

    Copyright (C) 1997-2011 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_WINDOWS

#include "../../core/windows/SDL_windows.h"

#include <mmsystem.h>

#include "SDL_timer.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);

}

#endif /* SDL_TIMER_WINDOWS */

/* vi: set ts=4 sw=4 expandtab: */