From 704c942545bbbdd227da60bdf64da74ed3fab6c2 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jaakko=20Ker=C3=A4nen?= <jaakko.keranen@iki.fi>
Date: Wed, 20 Nov 2013 12:16:47 +0200
Subject: [PATCH] Stereo 3D: Only use a stereo GL format if necessary

Whenever the VR mode changes, the canvas GL format is checked for
possible changes.
---
 doomsday/client/include/render/vr.h     | 17 +++++++++--------
 doomsday/client/src/render/vr.cpp       |  9 ++++++++-
 doomsday/client/src/ui/clientwindow.cpp | 11 ++++++++---
 3 files changed, 25 insertions(+), 12 deletions(-)

diff --git a/doomsday/client/include/render/vr.h b/doomsday/client/include/render/vr.h
index 4b1c0355ba..a5f2b72e60 100644
--- a/doomsday/client/include/render/vr.h
+++ b/doomsday/client/include/render/vr.h
@@ -80,14 +80,15 @@ void releaseViewPosition();
 bool viewPositionHeld();
 
 // Console variables
-Stereo3DMode mode(); /// Currently active Stereo3DMode index
-float riftFovX(); /// Horizontal field of view in Oculus Rift in degrees
-float riftLatency(); /// Estimated head-motion->photons latency, in seconds
-
-extern float ipd; /// Interpupillary distance in meters
-extern float playerHeight; /// Human player's real world height in meters
-extern float dominantEye; /// Kludge for aim-down-weapon-sight modes
-extern byte  swapEyes; /// When true, inverts stereoscopic effect
+Stereo3DMode mode(); ///< Currently active Stereo3DMode index
+bool modeNeedsStereoGLFormat(Stereo3DMode mode);
+float riftFovX(); ///< Horizontal field of view in Oculus Rift in degrees
+float riftLatency(); ///< Estimated head-motion->photons latency, in seconds
+
+extern float ipd; ///< Interpupillary distance in meters
+extern float playerHeight; ///< Human player's real world height in meters
+extern float dominantEye; ///< Kludge for aim-down-weapon-sight modes
+extern byte  swapEyes; ///< When true, inverts stereoscopic effect
 
 // Variables below are global, but not user visible //
 
diff --git a/doomsday/client/src/render/vr.cpp b/doomsday/client/src/render/vr.cpp
index d60a5fca9e..6a32c69c53 100644
--- a/doomsday/client/src/render/vr.cpp
+++ b/doomsday/client/src/render/vr.cpp
@@ -80,6 +80,11 @@ VR::Stereo3DMode VR::mode()
     return (VR::Stereo3DMode)vrMode;
 }
 
+bool VR::modeNeedsStereoGLFormat(VR::Stereo3DMode mode)
+{
+    return mode == VR::MODE_QUAD_BUFFERED;
+}
+
 static float vrRiftFovX = 114.8;
 float VR::riftFovX() /// Horizontal field of view in degrees
 {
@@ -134,7 +139,9 @@ static void vrModeChanged()
     if(ClientWindow::hasMain())
     {
         // The logical UI size may need to be changed.
-        ClientWindow::main().updateRootSize();
+        ClientWindow &win = ClientWindow::main();
+        win.updateRootSize();
+        win.updateCanvasFormat(); // possibly changes pixel format
     }
     if (VR::mode() == VR::MODE_OCULUS_RIFT) {
         if(Con_GetFloat("rend-camera-fov") != vrRiftFovX)
diff --git a/doomsday/client/src/ui/clientwindow.cpp b/doomsday/client/src/ui/clientwindow.cpp
index 956b56149f..1ff0e7098d 100644
--- a/doomsday/client/src/ui/clientwindow.cpp
+++ b/doomsday/client/src/ui/clientwindow.cpp
@@ -242,8 +242,6 @@ DENG2_OBSERVES(App,              GameChange)
         switch(newMode)
         {
         case Busy:
-            //busy->renderTransitionFrame();
-
             game->hide();
             game->disable();
             gameUI->hide();
@@ -258,6 +256,7 @@ DENG2_OBSERVES(App,              GameChange)
         default:
             busy->hide();
             busy->disable();
+
             game->show();
             game->enable();
             gameUI->show();
@@ -669,7 +668,13 @@ bool ClientWindow::setDefaultGLFormat() // static
     fmt.setDepthBufferSize(16);
     fmt.setStencilBufferSize(8);
     fmt.setDoubleBuffer(true);
-    fmt.setStereo(true);
+
+    if(VR::modeNeedsStereoGLFormat(VR::mode()))
+    {
+        // Only use a stereo format for modes that require it.
+        LOG_MSG("Using a stereoscopic format");
+        fmt.setStereo(true);
+    }
 
     if(CommandLine_Exists("-novsync") || !Con_GetByte("vid-vsync"))
     {