From 092331232b6f92c9465468c6e9d8d9129c5ab539 Mon Sep 17 00:00:00 2001
From: Philip Rebohle <philip.rebohle@tu-dortmund.de>
Date: Sat, 30 Jun 2018 18:49:29 +0200
Subject: [PATCH] [vr] Initialize and shut down OpenVR if necessary

---
 src/dxvk/dxvk_openvr.cpp | 60 ++++++++++++++++++++++++++++++----------
 src/dxvk/dxvk_openvr.h   | 10 ++++---
 2 files changed, 52 insertions(+), 18 deletions(-)

diff --git a/src/dxvk/dxvk_openvr.cpp b/src/dxvk/dxvk_openvr.cpp
index ac6e3cde3..7b77923c0 100644
--- a/src/dxvk/dxvk_openvr.cpp
+++ b/src/dxvk/dxvk_openvr.cpp
@@ -7,9 +7,20 @@
 
 #include <openvr/openvr.hpp>
 
+using VR_InitInternalProc        = vr::IVRSystem* (VR_CALLTYPE *)(vr::EVRInitError*, vr::EVRApplicationType);
+using VR_ShutdownInternalProc    = void  (VR_CALLTYPE *)();
+using VR_GetGenericInterfaceProc = void* (VR_CALLTYPE *)(const char*, vr::EVRInitError*);
+
 namespace dxvk {
   
-  VrInstance g_vrInstance;
+  struct VrFunctions {
+    VR_InitInternalProc        initInternal        = nullptr;
+    VR_ShutdownInternalProc    shutdownInternal    = nullptr;
+    VR_GetGenericInterfaceProc getGenericInterface = nullptr;
+  };
+  
+  VrFunctions g_vrFunctions;
+  VrInstance  g_vrInstance;
 
   VrInstance:: VrInstance() { }
   VrInstance::~VrInstance() { }
@@ -57,7 +68,7 @@ namespace dxvk {
     }
 
     if (m_initializedOpenVr)
-      /* shutdown */;
+      g_vrFunctions.shutdownInternal();
 
     m_initializedDevExt = true;
   }
@@ -79,7 +90,7 @@ namespace dxvk {
   }
   
   
-  vk::NameSet VrInstance::parseExtensionList(const std::string& str) {
+  vk::NameSet VrInstance::parseExtensionList(const std::string& str) const {
     vk::NameSet result;
     
     std::stringstream strstream(str);
@@ -93,9 +104,6 @@ namespace dxvk {
   
   
   vr::IVRCompositor* VrInstance::getCompositor() {
-    using GetGenericInterfaceProc = 
-      void* (VR_CALLTYPE *)(const char*, vr::EVRInitError*);
-    
     // Locate the OpenVR DLL if loaded by the process
     HMODULE ovrApi = ::GetModuleHandle("openvr_api.dll");
     
@@ -105,10 +113,11 @@ namespace dxvk {
     }
     
     // Load method used to retrieve the IVRCompositor interface
-    auto vrGetGenericInterface = reinterpret_cast<GetGenericInterfaceProc>(
-      ::GetProcAddress(ovrApi, "VR_GetGenericInterface"));
+    g_vrFunctions.initInternal        = reinterpret_cast<VR_InitInternalProc>       (::GetProcAddress(ovrApi, "VR_InitInternal"));
+    g_vrFunctions.shutdownInternal    = reinterpret_cast<VR_ShutdownInternalProc>   (::GetProcAddress(ovrApi, "VR_ShutdownInternal"));
+    g_vrFunctions.getGenericInterface = reinterpret_cast<VR_GetGenericInterfaceProc>(::GetProcAddress(ovrApi, "VR_GetGenericInterface"));
     
-    if (vrGetGenericInterface == nullptr) {
+    if (g_vrFunctions.getGenericInterface == nullptr) {
       Logger::warn("OpenVR: VR_GetGenericInterface not found");
       return nullptr;
     }
@@ -116,12 +125,35 @@ namespace dxvk {
     // Retrieve the compositor interface
     vr::EVRInitError error = vr::VRInitError_None;
     
-    auto compositor = reinterpret_cast<vr::IVRCompositor*>(
-      vrGetGenericInterface(vr::IVRCompositor_Version, &error));
+    vr::IVRCompositor* compositor = reinterpret_cast<vr::IVRCompositor*>(
+      g_vrFunctions.getGenericInterface(vr::IVRCompositor_Version, &error));
     
-    if (error != vr::VRInitError_None) {
-      Logger::warn(str::format("OpenVR: Failed to retrieve ", vr::IVRCompositor_Version));
-      return nullptr;
+    if (error != vr::VRInitError_None || compositor == nullptr) {
+      if (g_vrFunctions.initInternal     == nullptr
+       || g_vrFunctions.shutdownInternal == nullptr) {
+        Logger::warn("OpenVR: VR_InitInternal or VR_ShutdownInternal not found");
+        return nullptr;
+      }
+
+      // If the app has not initialized OpenVR yet, we need
+      // to do it now in order to grab a compositor instance
+      g_vrFunctions.initInternal(&error, vr::VRApplication_Background);
+      m_initializedOpenVr = error == vr::VRInitError_None;
+
+      if (error != vr::VRInitError_None) {
+        Logger::warn("OpenVR: Failed to initialize OpenVR");
+        return nullptr;
+      }
+
+      compositor = reinterpret_cast<vr::IVRCompositor*>(
+        g_vrFunctions.getGenericInterface(vr::IVRCompositor_Version, &error));
+      
+      if (error != vr::VRInitError_None || compositor == nullptr) {
+        Logger::warn("OpenVR: Failed to query compositor interface");
+        g_vrFunctions.shutdownInternal();
+        m_initializedOpenVr = false;
+        return nullptr;
+      }
     }
     
     Logger::info("OpenVR: Compositor interface found");
diff --git a/src/dxvk/dxvk_openvr.h b/src/dxvk/dxvk_openvr.h
index 1f96c2786..2d33aa3fe 100644
--- a/src/dxvk/dxvk_openvr.h
+++ b/src/dxvk/dxvk_openvr.h
@@ -7,12 +7,13 @@
 
 namespace vr {
   class IVRCompositor;
+  class IVRSystem;
 }
 
 namespace dxvk {
 
   class DxvkInstance;
-  
+
   /**
    * \brief OpenVR instance
    * 
@@ -64,7 +65,7 @@ namespace dxvk {
   private:
 
     std::mutex            m_mutex;
-    vr::IVRCompositor*    m_compositor;
+    vr::IVRCompositor*    m_compositor = nullptr;
 
     bool m_initializedOpenVr = false;
     bool m_initializedInsExt = false;
@@ -78,9 +79,10 @@ namespace dxvk {
     vk::NameSet queryDeviceExtensions(
             VkPhysicalDevice          adapter) const;
 
-    static vk::NameSet parseExtensionList(const std::string& str);
+    vk::NameSet parseExtensionList(
+      const std::string&              str) const;
     
-    static vr::IVRCompositor* getCompositor();
+    vr::IVRCompositor* getCompositor();
     
   };