From d0fdf175fd06fed09b92bc2fa248c6b645449ac4 Mon Sep 17 00:00:00 2001
From: Bradley Austin Davis <bdavis@saintandreas.org>
Date: Thu, 31 Aug 2017 15:21:47 -0700
Subject: [PATCH] Fix access to menu on background thread

---
 .../display-plugins/hmd/HmdDisplayPlugin.cpp  | 30 +++++++++----------
 .../display-plugins/hmd/HmdDisplayPlugin.h    |  2 --
 2 files changed, 14 insertions(+), 18 deletions(-)

diff --git a/libraries/display-plugins/src/display-plugins/hmd/HmdDisplayPlugin.cpp b/libraries/display-plugins/src/display-plugins/hmd/HmdDisplayPlugin.cpp
index aef5c73fa3..caeba37839 100644
--- a/libraries/display-plugins/src/display-plugins/hmd/HmdDisplayPlugin.cpp
+++ b/libraries/display-plugins/src/display-plugins/hmd/HmdDisplayPlugin.cpp
@@ -62,24 +62,9 @@ QRect HmdDisplayPlugin::getRecommendedOverlayRect() const {
     return CompositorHelper::VIRTUAL_SCREEN_RECOMMENDED_OVERLAY_RECT;
 }
 
-bool HmdDisplayPlugin::beginFrameRender(uint32_t frameIndex) {
-    if (!_vsyncEnabled && !_disablePreviewItemAdded) {
-        _container->addMenuItem(PluginType::DISPLAY_PLUGIN, MENU_PATH(), DISABLE_PREVIEW,
-            [this](bool clicked) {
-                _disablePreview = clicked;
-                _container->setBoolSetting("disableHmdPreview", _disablePreview);
-                if (_disablePreview) {
-                    _clearPreviewFlag = true;
-                }
-            }, true, _disablePreview);
-        _disablePreviewItemAdded = true;
-    }
-    return Parent::beginFrameRender(frameIndex);
-}
-
+#define DISABLE_PREVIEW_MENU_ITEM_DELAY_MS 500
 
 bool HmdDisplayPlugin::internalActivate() {
-    _disablePreviewItemAdded = false;
     _monoPreview = _container->getBoolSetting("monoPreview", DEFAULT_MONO_VIEW);
     _clearPreviewFlag = true;
     _container->addMenuItem(PluginType::DISPLAY_PLUGIN, MENU_PATH(), MONO_PREVIEW,
@@ -94,6 +79,19 @@ bool HmdDisplayPlugin::internalActivate() {
     _disablePreview = _container->getBoolSetting("disableHmdPreview", DEFAULT_DISABLE_PREVIEW || _vsyncEnabled);
 #endif
 
+    QTimer::singleShot(DISABLE_PREVIEW_MENU_ITEM_DELAY_MS, [this] {
+        if (isActive() && !_vsyncEnabled) {
+            _container->addMenuItem(PluginType::DISPLAY_PLUGIN, MENU_PATH(), DISABLE_PREVIEW,
+                [this](bool clicked) {
+                _disablePreview = clicked;
+                _container->setBoolSetting("disableHmdPreview", _disablePreview);
+                if (_disablePreview) {
+                    _clearPreviewFlag = true;
+                }
+            }, true, _disablePreview);
+        }
+    });
+
     _container->removeMenu(FRAMERATE);
     for_each_eye([&](Eye eye) {
         _eyeInverseProjections[eye] = glm::inverse(_eyeProjections[eye]);
diff --git a/libraries/display-plugins/src/display-plugins/hmd/HmdDisplayPlugin.h b/libraries/display-plugins/src/display-plugins/hmd/HmdDisplayPlugin.h
index 0827d04922..683c910b7c 100644
--- a/libraries/display-plugins/src/display-plugins/hmd/HmdDisplayPlugin.h
+++ b/libraries/display-plugins/src/display-plugins/hmd/HmdDisplayPlugin.h
@@ -51,7 +51,6 @@ protected:
     virtual void postPreview() {};
     virtual void updatePresentPose();
 
-    bool beginFrameRender(uint32_t frameIndex) override;
     bool internalActivate() override;
     void internalDeactivate() override;
     void compositeOverlay() override;
@@ -87,7 +86,6 @@ private:
     ivec4 getViewportForSourceSize(const uvec2& size) const;
     float getLeftCenterPixel() const;
 
-    bool _disablePreviewItemAdded { false };
     bool _monoPreview { true };
     bool _clearPreviewFlag { false };
     gpu::TexturePointer _previewTexture;