From e0a85521c9e2880776dbd5d4959461398931f128 Mon Sep 17 00:00:00 2001
From: Thilo Schulz <arny@ats.s.bawue.de>
Date: Mon, 31 Jan 2011 20:23:05 +0000
Subject: [PATCH] Explicitly set timer resolution on windows

---
 code/sys/sys_local.h |  1 +
 code/sys/sys_unix.c  | 11 +++++++++++
 code/sys/sys_win32.c | 33 +++++++++++++++++++++++++++++++++
 3 files changed, 45 insertions(+)

diff --git a/code/sys/sys_local.h b/code/sys/sys_local.h
index 71dade7d..08f4a0eb 100644
--- a/code/sys/sys_local.h
+++ b/code/sys/sys_local.h
@@ -51,6 +51,7 @@ char *Sys_StripAppBundle( char *pwd );
 void Sys_GLimpSafeInit( void );
 void Sys_GLimpInit( void );
 void Sys_PlatformInit( void );
+void Sys_PlatformExit( void );
 void Sys_SigHandler( int signal );
 void Sys_ErrorDialog( const char *error );
 void Sys_AnsiColorPrint( const char *msg );
diff --git a/code/sys/sys_unix.c b/code/sys/sys_unix.c
index e1b87ed2..a71b652a 100644
--- a/code/sys/sys_unix.c
+++ b/code/sys/sys_unix.c
@@ -739,6 +739,17 @@ void Sys_PlatformInit( void )
 		!( term && ( !strcmp( term, "raw" ) || !strcmp( term, "dumb" ) ) );
 }
 
+/*
+==============
+Sys_PlatformExit
+
+Unix specific deinitialisation
+==============
+*/
+void Sys_PlatformExit( void )
+{
+}
+
 /*
 ==============
 Sys_SetEnv
diff --git a/code/sys/sys_win32.c b/code/sys/sys_win32.c
index df0d474c..76a1cecc 100644
--- a/code/sys/sys_win32.c
+++ b/code/sys/sys_win32.c
@@ -41,6 +41,8 @@ Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 // Used to determine where to store user-specific files
 static char homePath[ MAX_OSPATH ] = { 0 };
 
+static UINT timerResolution = 0;
+
 #ifdef __WIN64__
 void Sys_SnapVector( float *v )
 {
@@ -696,6 +698,9 @@ Windows specific initialisation
 */
 void Sys_PlatformInit( void )
 {
+	TIMECAPS ptc;
+	UINT res;
+	
 #ifndef DEDICATED
 	const char *SDL_VIDEODRIVER = getenv( "SDL_VIDEODRIVER" );
 
@@ -708,6 +713,34 @@ void Sys_PlatformInit( void )
 	else
 		SDL_VIDEODRIVER_externallySet = qfalse;
 #endif
+
+	if(timeGetDevCaps(&ptc, sizeof(ptc)) == MMSYSERR_NOERROR)
+	{
+		timerResolution = ptc.wPeriodMin;
+
+		if(timerResolution > 1)
+		{
+			Com_Printf("Warning: Minimum supported timer resolution is %ums "
+				"on this system, recommended resolution 1ms\n", timerResolution);
+		}
+		
+		timeBeginPeriod(timerResolution);				
+	}
+	else
+		timerResolution = 0;
+}
+
+/*
+==============
+Sys_PlatformExit
+
+Windows specific initialisation
+==============
+*/
+void Sys_PlatformExit( void )
+{
+	if(timerResolution)
+		timeEndPeriod(timerResolution);
 }
 
 /*