Fix halo artifact on Oculus (#3119)

Fixes #3109

Author: bluemarvin

app/src/oculusvr/cpp/DeviceDelegateOculusVR.cpp

@@ -146,11 +146,6 @@ struct DeviceDelegateOculusVR::State {
       return;
     }
     initialized = true;
-    std::string version = vrapi_GetVersionString();
-    if (version.find("1.1.32.0") != std::string::npos) {
-      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);
@@ -1018,7 +1013,7 @@ DeviceDelegateOculusVR::EndFrame(const FrameEndMode aEndMode) {
 
   ovrLayerProjection2 projection = vrapi_DefaultLayerProjection2();
   projection.HeadPose = tracking.HeadPose;
-  projection.Header.SrcBlend = VRAPI_FRAME_LAYER_BLEND_ONE;
+  projection.Header.SrcBlend = VRAPI_FRAME_LAYER_BLEND_SRC_ALPHA;
   projection.Header.DstBlend = VRAPI_FRAME_LAYER_BLEND_ONE_MINUS_SRC_ALPHA;
   for (int i = 0; i < VRAPI_FRAME_LAYER_EYE_MAX; ++i) {
     const auto &eyeSwapChain = m.eyeSwapChains[i];

app/src/oculusvr/cpp/OculusVRLayers.cpp

@@ -87,7 +87,7 @@ void
 OculusLayerCylinder::Update(const ovrTracking2& aTracking, ovrTextureSwapChain* aClearSwapChain)  {
   OculusLayerSurface<VRLayerCylinderPtr, ovrLayerCylinder2>::Update(aTracking, aClearSwapChain);
   ovrLayer.HeadPose = aTracking.HeadPose;
-  ovrLayer.Header.SrcBlend = VRAPI_FRAME_LAYER_BLEND_ONE;
+  ovrLayer.Header.SrcBlend = VRAPI_FRAME_LAYER_BLEND_SRC_ALPHA;
   ovrLayer.Header.DstBlend = VRAPI_FRAME_LAYER_BLEND_ONE_MINUS_SRC_ALPHA;
 
   for ( int i = 0; i < VRAPI_FRAME_LAYER_EYE_MAX; i++ ) {

app/src/oculusvr/cpp/OculusVRLayers.h

@@ -174,7 +174,7 @@ class OculusLayerSurface : public OculusLayerBase<T, U> {
   void Init(JNIEnv *aEnv, vrb::RenderContextPtr &aContext) override {
     this->jniEnv = aEnv;
     this->contextWeak = aContext;
-    this->ovrLayer.Header.SrcBlend = VRAPI_FRAME_LAYER_BLEND_ONE;
+    this->ovrLayer.Header.SrcBlend = VRAPI_FRAME_LAYER_BLEND_SRC_ALPHA;
     this->ovrLayer.Header.DstBlend = VRAPI_FRAME_LAYER_BLEND_ONE_MINUS_SRC_ALPHA;
     if (this->swapChain) {
       return;