gfx/vr/VRServiceHost.h

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #ifndef GFX_VR_SERVICE_HOST_H
   8 #define GFX_VR_SERVICE_HOST_H
   9
  10 #include "mozilla/RefPtr.h"
  11 #include "nsISupportsImpl.h"
  12 #include "nsTArray.h"
  13
  14 #include <cstdint>
  15
  16 namespace mozilla {
  17 namespace gfx {
  18
  19 struct VRExternalShmem;
  20 class VRService;
  21
  22 /**
  23  * VRServiceHost is allocated as a singleton in the GPU process.
  24  * It is responsible for allocating VRService either within the GPU process
  25  * or in the VR process.
  26  * When the VR process is enabled, it maintains the state of the VR process,
  27  * starting and stopping it as needed.
  28  * VRServiceHost provides an interface that enables communication of the
  29  * VRService in the same way regardless of it running within the GPU process
  30  * or the VR process.
  31  */
  32
  33 class VRServiceHost {
  34   NS_INLINE_DECL_THREADSAFE_REFCOUNTING(mozilla::gfx::VRServiceHost)
  35  public:
  36   static void Init(bool aEnableVRProcess);
  37   static VRServiceHost* Get();
  38
  39   void Refresh();
  40   void StartService();
  41   void StopService();
  42   void Shutdown();
  43   void CreateService(volatile VRExternalShmem* aShmem);
  44   void NotifyVRProcessStarted();
  45   void CheckForPuppetCompletion();
  46
  47   void PuppetSubmit(const nsTArray<uint64_t>& aBuffer);
  48   void PuppetReset();
  49
  50  protected:
  51  private:
  52   explicit VRServiceHost(bool aEnableVRProcess);
  53   ~VRServiceHost();
  54
  55   void RefreshVRProcess();
  56   bool NeedVRProcess();
  57   void CreateVRProcess();
  58   void ShutdownVRProcess();
  59   void SendPuppetResetToVRProcess();
  60   void SendPuppetCheckForCompletionToVRProcess();
  61   void SendPuppetSubmitToVRProcess(const nsTArray<uint64_t>& aBuffer);
  62
  63   // Commands pending to be sent to the puppet device
  64   // once the VR service is started.
  65   nsTArray<uint64_t> mPuppetPendingCommands;
  66
  67   RefPtr<VRService> mVRService;
  68   // mVRProcessEnabled indicates that a separate, VR Process, should be used.
  69   // This may be false if the VR process is disabled with the
  70   // dom.vr.process.enabled preference or when the GPU process is disabled.
  71   // mVRProcessEnabled will not change once the browser is started and does not
  72   // reflect the started / stopped state of the VR Process.
  73   bool mVRProcessEnabled;
  74   // mVRProcessStarted is true when the VR Process is running.
  75   bool mVRProcessStarted;
  76   // mVRServiceReadyInVRProcess is true when the VR Process is running and the
  77   // VRService in the VR Process is ready to accept commands.
  78   bool mVRServiceReadyInVRProcess;
  79   // mVRServiceRequested is true when the VRService is needed.  This can be due
  80   // to Web API activity (WebXR, WebVR), browser activity (eg, VR Video
  81   // Playback), or a request to simulate a VR device with the VRServiceTest /
  82   // puppet API. mVRServiceRequested indicates the intended state of the VR
  83   // Service and is not an indication that the VR Service is ready to accept
  84   // requests or that the VR Process is enabled or running. Toggling the
  85   // mVRServiceRequested flag will result in the VR Service and/or the VR
  86   // Process either starting or stopping as needed.
  87   bool mVRServiceRequested;
  88 };
  89
  90 }  // namespace gfx
  91 }  // namespace mozilla
  92
  93 #endif  // GFX_VR_SERVICE_HOST_H