simplify like fuc

src/RageDisplay_OGL.cpp

@@ -22,6 +22,8 @@ using namespace RageDisplay_Legacy_Helpers;
 
 #include <set>
 
+#include <GL/wglew.h>
+
 #if defined(_MSC_VER)
 #pragma comment(lib, "opengl32.lib")
 #pragma comment(lib, "glu32.lib")
@@ -704,11 +706,6 @@ void RageDisplay_Legacy::ResolutionChanged()
 	RageDisplay::ResolutionChanged();
 }
 
-#if defined(WINDOWS)
-	typedef BOOL (APIENTRY *PFNWGLSWAPINTERVALFARPROC)( int );
-	PFNWGLSWAPINTERVALFARPROC wglSwapIntervalEXT = 0;
-#endif
-
 // Return true if mode change was successful.
 // bNewDeviceOut is set true if a new device was created and textures
 // need to be reloaded.
@@ -744,17 +741,14 @@ RString RageDisplay_Legacy::TryVideoMode( const VideoModeParams &p, bool &bNewDe
 		InitShaders();
 	}
 
-	const char *extensions = reinterpret_cast<const char *>(glGetString( GL_EXTENSIONS ));
 // I'm not sure this is correct -Colby
 #if defined(WINDOWS)
-	if( strstr( extensions, "WGL_EXT_swap_control" ) == 0 )
-		return RString("The WGL_EXT_swap_control extension is not supported on your computer.");
-
 	/* Set vsync the Windows way, if we can.  (What other extensions are there
 	 * to do this, for other archs?) */
-	wglSwapIntervalEXT = (PFNWGLSWAPINTERVALFARPROC)wglGetProcAddress( "wglSwapIntervalEXT" );
-	if (wglSwapIntervalEXT)
+	if( wglewIsSupported("WGL_EXT_swap_control") )
 		wglSwapIntervalEXT(p.vsync);
+	else
+		return RString("The WGL_EXT_swap_control extension is not supported on your computer.");
 #endif
 	
 	ResolutionChanged();