From b53941070a7c50a2dfbf80d29ee7b8eca8998a6e Mon Sep 17 00:00:00 2001
From: Imanol Fernandez <mortimergoro@gmail.com>
Date: Fri, 3 Apr 2020 21:42:57 +0200
Subject: [PATCH] Workaround for Oculus Layers halo artifact (#3105)

---
 app/src/oculusvr/cpp/DeviceDelegateOculusVR.cpp | 9 ++++-----
 app/src/oculusvr/cpp/OculusVRLayers.cpp         | 7 ++++++-
 app/src/oculusvr/cpp/OculusVRLayers.h           | 1 +
 3 files changed, 11 insertions(+), 6 deletions(-)

diff --git a/app/src/oculusvr/cpp/DeviceDelegateOculusVR.cpp b/app/src/oculusvr/cpp/DeviceDelegateOculusVR.cpp
index 8bdf55d77..abd499d4b 100644
--- a/app/src/oculusvr/cpp/DeviceDelegateOculusVR.cpp
+++ b/app/src/oculusvr/cpp/DeviceDelegateOculusVR.cpp
@@ -148,12 +148,11 @@ struct DeviceDelegateOculusVR::State {
     initialized = true;
     std::string version = vrapi_GetVersionString();
     if (version.find("1.1.32.0") != std::string::npos) {
-      VRB_ERROR("Disable layers due to driver bug. VRAPI Runtime Version: %s", vrapi_GetVersionString());
-      layersEnabled = false;
-      VRBrowser::DisableLayers();
-    } else {
-      layersEnabled = VRBrowser::AreLayersEnabled();
+      VRB_ERROR("Force layer clip due to driver bug. VRAPI Runtime Version: %s",vrapi_GetVersionString());
+      OculusLayer::sForceClip = true;
     }
+
+    layersEnabled = VRBrowser::AreLayersEnabled();
     SetRenderSize(device::RenderMode::StandAlone);
 
     for (int i = 0; i < VRAPI_EYE_COUNT; ++i) {
diff --git a/app/src/oculusvr/cpp/OculusVRLayers.cpp b/app/src/oculusvr/cpp/OculusVRLayers.cpp
index a751ab09a..28f766183 100644
--- a/app/src/oculusvr/cpp/OculusVRLayers.cpp
+++ b/app/src/oculusvr/cpp/OculusVRLayers.cpp
@@ -12,6 +12,7 @@ static ovrMatrix4f ovrMatrixFrom(const vrb::Matrix &aMatrix) {
   return m;
 }
 
+bool OculusLayer::sForceClip = false;
 
 // OculusLayerQuad
 
@@ -40,7 +41,7 @@ OculusLayerQuad::Update(const ovrTracking2& aTracking, ovrTextureSwapChain* aCle
   vrb::Matrix scale = vrb::Matrix::Identity();
   scale.ScaleInPlace(vrb::Vector(w * 0.5f, h * 0.5f, 1.0f));
 
-  bool clip = false;
+  bool clip = sForceClip;
 
   for (int i = 0; i < VRAPI_FRAME_LAYER_EYE_MAX; ++i) {
     device::Eye eye = i == 0 ? device::Eye::Left : device::Eye::Right;
@@ -108,6 +109,10 @@ OculusLayerCylinder::Update(const ovrTracking2& aTracking, ovrTextureSwapChain*
     ovrLayer.Textures[i].TextureRect.width = 1.0f;
     ovrLayer.Textures[i].TextureRect.height = 1.0f;
   }
+
+  if (sForceClip) {
+    SetClipEnabled(true);
+  }
 }
 
 
diff --git a/app/src/oculusvr/cpp/OculusVRLayers.h b/app/src/oculusvr/cpp/OculusVRLayers.h
index 59495b7c3..c9440c646 100644
--- a/app/src/oculusvr/cpp/OculusVRLayers.h
+++ b/app/src/oculusvr/cpp/OculusVRLayers.h
@@ -30,6 +30,7 @@ typedef std::weak_ptr<SurfaceChangedTarget> SurfaceChangedTargetWeakPtr;
 
 class OculusLayer {
 public:
+  static bool sForceClip;
   virtual void Init(JNIEnv *aEnv, vrb::RenderContextPtr &aContext) = 0;
   virtual void Update(const ovrTracking2 &aTracking, ovrTextureSwapChain *aClearSwapChain) = 0;
   virtual ovrTextureSwapChain *GetSwapChain() const = 0;