Add "VR Mode" option in menu

Author: phoboslab

Quake/menu.c

@@ -87,6 +87,8 @@ enum m_state_e	m_return_state;
 qboolean	m_return_onerror;
 char		m_return_reason [32];
 
+extern	cvar_t	vr_enabled;
+
 #define StartingGame	(m_multiplayer_cursor == 1)
 #define JoiningGame		(m_multiplayer_cursor == 0)
 #define	IPXConfig		(m_net_cursor == 0)
@@ -959,6 +961,7 @@ enum
 	OPT_ALWAYSMLOOK,
 	OPT_LOOKSPRING,
 	OPT_LOOKSTRAFE,
+	OPT_VR,
 //#ifdef _WIN32
 //	OPT_USEMOUSE,
 //#endif
@@ -1069,6 +1072,10 @@ void M_AdjustSliders (int dir)
 	case OPT_LOOKSTRAFE:	// lookstrafe
 		Cvar_Set ("lookstrafe", lookstrafe.value ? "0" : "1");
 		break;
+
+	case OPT_VR:
+		Cvar_Set ("vr_enabled", vr_enabled.value ? "0" : "1");
+		break;
 	}
 }
 
@@ -1179,6 +1186,10 @@ void M_Options_Draw (void)
 	M_Print (16, 32 + 8*OPT_LOOKSTRAFE,	"            Lookstrafe");
 	M_DrawCheckbox (220, 32 + 8*OPT_LOOKSTRAFE, lookstrafe.value);
 
+	// OPT_VR:
+	M_Print (16, 32 + 8*OPT_VR,	        "               VR Mode");
+	M_DrawCheckbox (220, 32 + 8*OPT_VR, vr_enabled.value);
+
 	// OPT_VIDEO:
 	if (vid_menudrawfn)
 		M_Print (16, 32 + 8*OPT_VIDEO,	"         Video Options");

Quake/vr.c

@@ -332,9 +332,18 @@ void VR_UpdateScreenContent()
 	ovrLayerEyeFov ld;
 	ovrLayerHeader* layers;
 
-	GLint w = mirror_texture->OGL.Header.TextureSize.w;
-	GLint h = mirror_texture->OGL.Header.TextureSize.h;
+	GLint w, h;
 
+	
+	// Last chance to enable VR Mode - we get here when the game already start up with vr_enabled 1
+	// If enabling fails, unset the cvar and return.
+	if( !vr_initialized && !VR_Enable() ) {
+		Cvar_Set ("vr_enabled", "0");
+		return;
+	}
+
+	w = mirror_texture->OGL.Header.TextureSize.w;
+	h= mirror_texture->OGL.Header.TextureSize.h;
 
 	// Get current orientation of the HMD
 	ftiming = ovrHmd_GetFrameTiming(hmd, 0);