- avoid checking for vr_enable_quadbuffered directly.

This option only exists on Windows, so on the other platforms it should not be in the menu and not affect the setup of the VR mode.

src/gl/stereo3d/gl_stereo_cvars.cpp

@@ -88,7 +88,7 @@ const Stereo3DMode& Stereo3DMode::getCurrentMode()
 		setCurrentMode(RightEyeView::getInstance(vr_ipd));
 		break;
 	case 7:
-		if (vr_enable_quadbuffered) {
+		if (screen->enable_quadbuffered) {
 			setCurrentMode(QuadStereo::getInstance(vr_ipd));
 		}
 		else {

src/v_video.h

@@ -349,6 +349,7 @@ protected:
 public:
 	int hwcaps = 0;
 	int instack[2] = { 0,0 };	// this is globally maintained state for portal recursion avoidance.
+	bool enable_quadbuffered = false;
 
 	IntRect mScreenViewport;
 	IntRect mSceneViewport;

src/win32/win32gliface.cpp

@@ -81,6 +81,7 @@ CUSTOM_CVAR(Bool, gl_debug, false, CVAR_ARCHIVE | CVAR_GLOBALCONFIG | CVAR_NOINI
 CUSTOM_CVAR(Bool, vr_enable_quadbuffered, false, CVAR_ARCHIVE | CVAR_GLOBALCONFIG | CVAR_NOINITCALL)
 {
 	Printf("You must restart " GAMENAME " to switch quad stereo mode\n");
+	screen->enable_quadbuffered = self;
 }
 
 EXTERN_CVAR(Int, vid_refreshrate)

wadsrc/static/menudef.txt

@@ -2235,7 +2235,10 @@ OptionMenu "OpenGLOptions" protected
 	Slider "$GLPREFMNU_MENUBLUR",				gl_menu_blur, 0, 5.0, 0.5, 2
 	StaticText " "
 	Option "$GLPREFMNU_VRMODE",					vr_mode, 						"VRMode"
-	Option "$GLPREFMNU_VRQUADSTEREO",			vr_enable_quadbuffered,			"OnOff"
+	IfOption(Windows)
+	{
+		Option "$GLPREFMNU_VRQUADSTEREO",			vr_enable_quadbuffered,			"OnOff"
+	}
 	StaticText " "
 	Option "$GLPREFMNU_MULTISAMPLE", 			gl_multisample,					"Multisample"
 	Option "$GLPREFMNU_TONEMAP", 				gl_tonemap,						"TonemapModes"