Adding Chrome-side WebVR interface

content/browser/vr/vr_device_manager.cc

+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "content/browser/vr/vr_device_manager.h"
+
+#include "base/memory/singleton.h"
+#include "third_party/WebKit/public/platform/WebVR.h"
+
+#if defined(OS_ANDROID)
+#include "content/browser/vr/android/cardboard/cardboard_vr_device_provider.h"
+#endif
+
+namespace content {
+
+namespace {
+VRDeviceManager* g_vr_device_manager = nullptr;
+}
+
+VRDeviceManager::VRDeviceManager() :
+    vr_initialized_(false),
+    keep_alive_(false) {
+#if defined(OS_ANDROID)
+  scoped_ptr<VRDeviceProvider> cardboard_provider(
+      new CardboardVRDeviceProvider());
+  RegisterProvider(cardboard_provider.Pass());
+#endif
+}
+
+VRDeviceManager::VRDeviceManager(scoped_ptr<VRDeviceProvider> provider)
+    : vr_initialized_(false), keep_alive_(true) {
+  thread_checker_.DetachFromThread();
+  RegisterProvider(provider.Pass());
+  SetInstance(this);
+}
+
+VRDeviceManager::~VRDeviceManager() {
+  DCHECK(thread_checker_.CalledOnValidThread());
+  g_vr_device_manager = nullptr;
+}
+
+VRDeviceManager* VRDeviceManager::GetInstance() {
+  if (!g_vr_device_manager)
+    g_vr_device_manager = new VRDeviceManager();
+  return g_vr_device_manager;
+}
+
+void VRDeviceManager::SetInstance(VRDeviceManager* instance) {
+  // Unit tests can create multiple instances but only one should exist at any
+  // given time so g_vr_device_manager should only go from nullptr to
+  // non-nullptr and vica versa.
+  CHECK_NE(!!instance, !!g_vr_device_manager);
+  g_vr_device_manager = instance;
+}
+
+bool VRDeviceManager::HasInstance() {
+  // For testing. Checks to see if a VRDeviceManager instance is active.
+  return !!g_vr_device_manager;
+}
+
+mojo::Array<VRDeviceInfoPtr> VRDeviceManager::GetVRDevices() {
+  DCHECK(thread_checker_.CalledOnValidThread());
+
+  InitializeProviders();
+
+  std::vector<VRDevice*> devices;
+  ProviderList::iterator iter;
+  for (iter = providers_.begin(); iter != providers_.end(); ++iter) {
+    (*iter)->GetDevices(devices);
+  }
+
+  mojo::Array<VRDeviceInfoPtr> out_devices(0);
+  std::vector<VRDevice*>::iterator diter;
+  for (diter = devices.begin(); diter != devices.end(); ++diter) {
+    VRDevice* device = *diter;
+
+    if (device->id() == VR_DEVICE_LAST_ID)
+      continue;
+
+    if (devices_.find(device->id()) == devices_.end()) {
+      devices_[device->id()] = device;
+    }
+
+    VRDeviceInfoPtr vr_device_info = device->GetVRDevice();
+    if (vr_device_info.is_null())
+      continue;
+
+    vr_device_info->index = device->id();
+    out_devices.push_back(vr_device_info.Pass());
+  }
+
+  return out_devices;
+}
+
+VRDevice* VRDeviceManager::GetDevice(unsigned int index) {
+  DCHECK(thread_checker_.CalledOnValidThread());
+
+  DeviceMap::iterator iter = devices_.find(index);
+  if (iter == devices_.end()) {
+    return nullptr;
+  }
+  return iter->second;
+}
+
+void VRDeviceManager::AddService(mojo::InterfaceImpl<VRService>* service) {
+  VRDeviceManager* device_manager = GetInstance();
+  DCHECK(device_manager->thread_checker_.CalledOnValidThread());
+
+  // Explicitly does not initialize the providers. That's done lazily the first
+  // time GetVRDevices is called.
+  device_manager->services_.insert(service);
+}
+
+void VRDeviceManager::RemoveService(mojo::InterfaceImpl<VRService>* service) {
+  CHECK(g_vr_device_manager);
+  DCHECK(g_vr_device_manager->thread_checker_.CalledOnValidThread());
+
+  ServiceSet::iterator it = g_vr_device_manager->services_.find(service);
+  DCHECK(it != g_vr_device_manager->services_.end());
+
+  if (it != g_vr_device_manager->services_.end()) {
+    g_vr_device_manager->services_.erase(it);
+    if (g_vr_device_manager->services_.size() == 0
+        && !g_vr_device_manager->keep_alive_) {
+      // Delete the device manager when it has no services left.
+      delete g_vr_device_manager;
+    }
+  }
+}
+
+void VRDeviceManager::InitializeProviders() {
+  if (vr_initialized_) {
+    return;
+  }
+
+  ProviderList::iterator iter;
+  for (iter = providers_.begin(); iter != providers_.end(); ++iter) {
+    (*iter)->Initialize();
+  }
+
+  vr_initialized_ = true;
+}
+
+void VRDeviceManager::RegisterProvider(scoped_ptr<VRDeviceProvider> provider) {
+  providers_.push_back(make_linked_ptr(provider.release()));
+}
+
+}  // namespace content