1 files changed, 523 insertions, 0 deletions
diff --git a/dom/vr/XRSession.cpp b/dom/vr/XRSession.cpp
new file mode 100644
index 0000000000..016e7a0bc5
--- /dev/null
+++ b/dom/vr/XRSession.cpp
@@ -0,0 +1,523 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "mozilla/dom/XRSession.h"
+
+#include "mozilla/dom/XRSessionEvent.h"
+#include "mozilla/dom/XRInputSourceEvent.h"
+#include "mozilla/EventDispatcher.h"
+#include "mozilla/dom/DocumentInlines.h"
+#include "mozilla/dom/Promise.h"
+#include "XRSystem.h"
+#include "XRRenderState.h"
+#include "XRBoundedReferenceSpace.h"
+#include "XRFrame.h"
+#include "XRNativeOrigin.h"
+#include "XRNativeOriginFixed.h"
+#include "XRNativeOriginViewer.h"
+#include "XRNativeOriginLocal.h"
+#include "XRNativeOriginLocalFloor.h"
+#include "XRView.h"
+#include "XRViewerPose.h"
+#include "VRLayerChild.h"
+#include "XRInputSourceArray.h"
+#include "nsGlobalWindow.h"
+#include "nsIObserverService.h"
+#include "nsISupportsPrimitives.h"
+#include "nsRefreshDriver.h"
+#include "VRDisplayClient.h"
+#include "VRDisplayPresentation.h"
+
+/**
+ * Maximum instances of XRFrame and XRViewerPose objects
+ * created in the pool.
+ */
+const uint32_t kMaxPoolSize = 16;
+
+namespace mozilla {
+namespace dom {
+
+NS_IMPL_CYCLE_COLLECTION_CLASS(XRSession)
+
+NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_INHERITED(XRSession,
+                                                  DOMEventTargetHelper)
+  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mXRSystem)
+  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mActiveRenderState)
+  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mPendingRenderState)
+  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mInputSources)
+  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mViewerPosePool)
+  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mFramePool)
+
+  for (uint32_t i = 0; i < tmp->mFrameRequestCallbacks.Length(); ++i) {
+    NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(cb, "mFrameRequestCallbacks[i]");
+    cb.NoteXPCOMChild(tmp->mFrameRequestCallbacks[i].mCallback);
+  }
+
+NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
+
+NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN_INHERITED(XRSession, DOMEventTargetHelper)
+  NS_IMPL_CYCLE_COLLECTION_UNLINK(mXRSystem)
+  NS_IMPL_CYCLE_COLLECTION_UNLINK(mActiveRenderState)
+  NS_IMPL_CYCLE_COLLECTION_UNLINK(mPendingRenderState)
+  NS_IMPL_CYCLE_COLLECTION_UNLINK(mInputSources)
+  NS_IMPL_CYCLE_COLLECTION_UNLINK(mViewerPosePool)
+  NS_IMPL_CYCLE_COLLECTION_UNLINK(mFramePool)
+
+  tmp->mFrameRequestCallbacks.Clear();
+
+  // Don't need NS_IMPL_CYCLE_COLLECTION_UNLINK_PRESERVED_WRAPPER because
+  // DOMEventTargetHelper does it for us.
+NS_IMPL_CYCLE_COLLECTION_UNLINK_END
+
+NS_IMPL_ISUPPORTS_CYCLE_COLLECTION_INHERITED_0(XRSession, DOMEventTargetHelper)
+
+already_AddRefed<XRSession> XRSession::CreateInlineSession(
+    nsPIDOMWindowInner* aWindow, XRSystem* aXRSystem,
+    const nsTArray<XRReferenceSpaceType>& aEnabledReferenceSpaceTypes) {
+  nsGlobalWindowInner* win = nsGlobalWindowInner::Cast(aWindow);
+  if (!win) {
+    return nullptr;
+  }
+  Document* doc = aWindow->GetExtantDoc();
+  if (!doc) {
+    return nullptr;
+  }
+  nsPresContext* context = doc->GetPresContext();
+  if (!context) {
+    return nullptr;
+  }
+  nsRefreshDriver* driver = context->RefreshDriver();
+  if (!driver) {
+    return nullptr;
+  }
+
+  RefPtr<XRSession> session =
+      new XRSession(aWindow, aXRSystem, driver, nullptr, gfx::kVRGroupContent,
+                    aEnabledReferenceSpaceTypes);
+  driver->AddRefreshObserver(session, FlushType::Display, "XR Session");
+  return session.forget();
+}
+
+already_AddRefed<XRSession> XRSession::CreateImmersiveSession(
+    nsPIDOMWindowInner* aWindow, XRSystem* aXRSystem,
+    gfx::VRDisplayClient* aClient, uint32_t aPresentationGroup,
+    const nsTArray<XRReferenceSpaceType>& aEnabledReferenceSpaceTypes) {
+  RefPtr<XRSession> session =
+      new XRSession(aWindow, aXRSystem, nullptr, aClient, aPresentationGroup,
+                    aEnabledReferenceSpaceTypes);
+  return session.forget();
+}
+
+XRSession::XRSession(
+    nsPIDOMWindowInner* aWindow, XRSystem* aXRSystem,
+    nsRefreshDriver* aRefreshDriver, gfx::VRDisplayClient* aClient,
+    uint32_t aPresentationGroup,
+    const nsTArray<XRReferenceSpaceType>& aEnabledReferenceSpaceTypes)
+    : DOMEventTargetHelper(aWindow),
+      mXRSystem(aXRSystem),
+      mShutdown(false),
+      mEnded(false),
+      mRefreshDriver(aRefreshDriver),
+      mDisplayClient(aClient),
+      mFrameRequestCallbackCounter(0),
+      mEnabledReferenceSpaceTypes(aEnabledReferenceSpaceTypes.Clone()),
+      mViewerPosePoolIndex(0),
+      mFramePoolIndex(0) {
+  if (aClient) {
+    aClient->SessionStarted(this);
+  }
+  mActiveRenderState = new XRRenderState(aWindow, this);
+  mStartTimeStamp = TimeStamp::Now();
+  if (IsImmersive()) {
+    mDisplayPresentation =
+        mDisplayClient->BeginPresentation({}, aPresentationGroup);
+  }
+  if (mDisplayClient) {
+    mDisplayClient->SetXRAPIMode(gfx::VRAPIMode::WebXR);
+  }
+  // TODO: Handle XR input sources are no longer available cases.
+  // https://immersive-web.github.io/webxr/#dom-xrsession-inputsources
+  mInputSources = new XRInputSourceArray(aWindow);
+}
+
+XRSession::~XRSession() { MOZ_ASSERT(mShutdown); }
+
+gfx::VRDisplayClient* XRSession::GetDisplayClient() const {
+  return mDisplayClient;
+}
+
+JSObject* XRSession::WrapObject(JSContext* aCx,
+                                JS::Handle<JSObject*> aGivenProto) {
+  return XRSession_Binding::Wrap(aCx, this, aGivenProto);
+}
+
+bool XRSession::IsEnded() const { return mEnded; }
+
+already_AddRefed<Promise> XRSession::End(ErrorResult& aRv) {
+  nsCOMPtr<nsIGlobalObject> global = GetParentObject();
+  NS_ENSURE_TRUE(global, nullptr);
+
+  ExitPresentInternal();
+
+  RefPtr<Promise> promise = Promise::Create(global, aRv);
+  NS_ENSURE_TRUE(!aRv.Failed(), nullptr);
+
+  promise->MaybeResolve(JS::UndefinedHandleValue);
+
+  return promise.forget();
+}
+
+bool XRSession::IsImmersive() const {
+  // Only immersive sessions have a VRDisplayClient
+  return mDisplayClient != nullptr;
+}
+
+XRVisibilityState XRSession::VisibilityState() {
+  return XRVisibilityState::Visible;
+  // TODO (Bug 1609771): Implement changing visibility state
+}
+
+// https://immersive-web.github.io/webxr/#dom-xrsession-updaterenderstate
+void XRSession::UpdateRenderState(const XRRenderStateInit& aNewState,
+                                  ErrorResult& aRv) {
+  if (mEnded) {
+    aRv.ThrowInvalidStateError(
+        "UpdateRenderState can not be called on an XRSession that has ended.");
+    return;
+  }
+  if (aNewState.mBaseLayer.WasPassed() &&
+      aNewState.mBaseLayer.Value()->mSession != this) {
+    aRv.ThrowInvalidStateError(
+        "The baseLayer passed in to UpdateRenderState must "
+        "belong to the XRSession that UpdateRenderState is "
+        "being called on.");
+    return;
+  }
+  if (aNewState.mInlineVerticalFieldOfView.WasPassed() && IsImmersive()) {
+    aRv.ThrowInvalidStateError(
+        "The inlineVerticalFieldOfView can not be set on an "
+        "XRRenderState for an immersive XRSession.");
+    return;
+  }
+  if (mPendingRenderState == nullptr) {
+    mPendingRenderState = new XRRenderState(*mActiveRenderState);
+  }
+  if (aNewState.mDepthNear.WasPassed()) {
+    mPendingRenderState->SetDepthNear(aNewState.mDepthNear.Value());
+  }
+  if (aNewState.mDepthFar.WasPassed()) {
+    mPendingRenderState->SetDepthFar(aNewState.mDepthFar.Value());
+  }
+  if (aNewState.mInlineVerticalFieldOfView.WasPassed()) {
+    mPendingRenderState->SetInlineVerticalFieldOfView(
+        aNewState.mInlineVerticalFieldOfView.Value());
+  }
+  if (aNewState.mBaseLayer.WasPassed()) {
+    mPendingRenderState->SetBaseLayer(aNewState.mBaseLayer.Value());
+  }
+}
+
+XRRenderState* XRSession::RenderState() { return mActiveRenderState; }
+
+XRInputSourceArray* XRSession::InputSources() { return mInputSources; }
+
+// https://immersive-web.github.io/webxr/#apply-the-pending-render-state
+void XRSession::ApplyPendingRenderState() {
+  if (mPendingRenderState == nullptr) {
+    return;
+  }
+  mActiveRenderState = mPendingRenderState;
+  mPendingRenderState = nullptr;
+
+  // https://immersive-web.github.io/webxr/#minimum-inline-field-of-view
+  const double kMinimumInlineVerticalFieldOfView = 0.0f;
+
+  // https://immersive-web.github.io/webxr/#maximum-inline-field-of-view
+  const double kMaximumInlineVerticalFieldOfView = M_PI;
+
+  if (!mActiveRenderState->GetInlineVerticalFieldOfView().IsNull()) {
+    double verticalFOV =
+        mActiveRenderState->GetInlineVerticalFieldOfView().Value();
+    if (verticalFOV < kMinimumInlineVerticalFieldOfView) {
+      verticalFOV = kMinimumInlineVerticalFieldOfView;
+    }
+    if (verticalFOV > kMaximumInlineVerticalFieldOfView) {
+      verticalFOV = kMaximumInlineVerticalFieldOfView;
+    }
+    mActiveRenderState->SetInlineVerticalFieldOfView(verticalFOV);
+  }
+
+  // Our minimum near plane value is set to a small value close but not equal to
+  // zero (kEpsilon) The maximum far plane is infinite.
+  const float kEpsilon = 0.00001f;
+  double depthNear = mActiveRenderState->DepthNear();
+  double depthFar = mActiveRenderState->DepthFar();
+  if (depthNear < 0.0f) {
+    depthNear = 0.0f;
+  }
+  if (depthFar < 0.0f) {
+    depthFar = 0.0f;
+  }
+  // Ensure at least a small distance between the near and far planes
+  if (fabs(depthFar - depthNear) < kEpsilon) {
+    depthFar = depthNear + kEpsilon;
+  }
+  mActiveRenderState->SetDepthNear(depthNear);
+  mActiveRenderState->SetDepthFar(depthFar);
+
+  XRWebGLLayer* baseLayer = mActiveRenderState->GetBaseLayer();
+  if (baseLayer) {
+    if (!IsImmersive() && baseLayer->mCompositionDisabled) {
+      mActiveRenderState->SetCompositionDisabled(true);
+      mActiveRenderState->SetOutputCanvas(baseLayer->GetCanvas());
+    } else {
+      mActiveRenderState->SetCompositionDisabled(false);
+      mActiveRenderState->SetOutputCanvas(nullptr);
+      mDisplayPresentation->UpdateXRWebGLLayer(baseLayer);
+    }
+  }  // if (baseLayer)
+}
+
+void XRSession::WillRefresh(mozilla::TimeStamp aTime) {
+  // Inline sessions are driven by nsRefreshDriver directly,
+  // unlike immersive sessions, which are driven VRDisplayClient.
+  if (!IsImmersive() && !mXRSystem->HasActiveImmersiveSession()) {
+    nsGlobalWindowInner* win = nsGlobalWindowInner::Cast(GetOwner());
+    if (win) {
+      if (JSObject* obj = win->AsGlobal()->GetGlobalJSObject()) {
+        js::NotifyAnimationActivity(obj);
+      }
+    }
+    StartFrame();
+  }
+}
+
+void XRSession::StartFrame() {
+  if (mShutdown || mEnded) {
+    return;
+  }
+  ApplyPendingRenderState();
+
+  XRWebGLLayer* baseLayer = mActiveRenderState->GetBaseLayer();
+  if (!baseLayer) {
+    return;
+  }
+
+  if (!IsImmersive() && mActiveRenderState->GetOutputCanvas() == nullptr) {
+    return;
+  }
+
+  // Determine timestamp for the callbacks
+  TimeStamp nowTime = TimeStamp::Now();
+  mozilla::TimeDuration duration = nowTime - mStartTimeStamp;
+  DOMHighResTimeStamp timeStamp = duration.ToMilliseconds();
+
+  // Create an XRFrame for the callbacks
+  RefPtr<XRFrame> frame = PooledFrame();
+  frame->StartAnimationFrame();
+
+  baseLayer->StartAnimationFrame();
+  nsTArray<XRFrameRequest> callbacks;
+  callbacks.AppendElements(mFrameRequestCallbacks);
+  mFrameRequestCallbacks.Clear();
+  for (auto& callback : callbacks) {
+    callback.Call(timeStamp, *frame);
+  }
+
+  baseLayer->EndAnimationFrame();
+  frame->EndAnimationFrame();
+  if (mDisplayPresentation) {
+    mDisplayPresentation->SubmitFrame();
+  }
+}
+
+void XRSession::ExitPresent() { ExitPresentInternal(); }
+
+already_AddRefed<Promise> XRSession::RequestReferenceSpace(
+    const XRReferenceSpaceType& aReferenceSpaceType, ErrorResult& aRv) {
+  nsCOMPtr<nsIGlobalObject> global = GetParentObject();
+  NS_ENSURE_TRUE(global, nullptr);
+
+  RefPtr<Promise> promise = Promise::Create(global, aRv);
+  NS_ENSURE_TRUE(!aRv.Failed(), nullptr);
+
+  if (!mEnabledReferenceSpaceTypes.Contains(aReferenceSpaceType)) {
+    promise->MaybeRejectWithNotSupportedError(nsLiteralCString(
+        "Requested XRReferenceSpaceType not available for the XRSession."));
+    return promise.forget();
+  }
+  RefPtr<XRReferenceSpace> space;
+  RefPtr<XRNativeOrigin> nativeOrigin;
+  if (mDisplayClient) {
+    switch (aReferenceSpaceType) {
+      case XRReferenceSpaceType::Viewer:
+        nativeOrigin = new XRNativeOriginViewer(mDisplayClient);
+        break;
+      case XRReferenceSpaceType::Local:
+        nativeOrigin = new XRNativeOriginLocal(mDisplayClient);
+        break;
+      case XRReferenceSpaceType::Local_floor:
+      case XRReferenceSpaceType::Bounded_floor:
+        nativeOrigin = new XRNativeOriginLocalFloor(mDisplayClient);
+        break;
+      default:
+        nativeOrigin = new XRNativeOriginFixed(gfx::PointDouble3D());
+        break;
+    }
+  } else {
+    // We currently only support XRReferenceSpaceType::Viewer when
+    // there is no XR hardware.  In this case, the native origin
+    // will always be at {0, 0, 0} which will always be the same
+    // as the 'tracked' position of the non-existant pose.
+    MOZ_ASSERT(aReferenceSpaceType == XRReferenceSpaceType::Viewer);
+    nativeOrigin = new XRNativeOriginFixed(gfx::PointDouble3D());
+  }
+  if (aReferenceSpaceType == XRReferenceSpaceType::Bounded_floor) {
+    space = new XRBoundedReferenceSpace(GetParentObject(), this, nativeOrigin);
+  } else {
+    space = new XRReferenceSpace(GetParentObject(), this, nativeOrigin,
+                                 aReferenceSpaceType);
+  }
+
+  promise->MaybeResolve(space);
+  return promise.forget();
+}
+
+XRRenderState* XRSession::GetActiveRenderState() const {
+  return mActiveRenderState;
+}
+
+void XRSession::XRFrameRequest::Call(const DOMHighResTimeStamp& aTimeStamp,
+                                     XRFrame& aFrame) {
+  RefPtr<mozilla::dom::XRFrameRequestCallback> callback = mCallback;
+  callback->Call(aTimeStamp, aFrame);
+}
+
+int32_t XRSession::RequestAnimationFrame(XRFrameRequestCallback& aCallback,
+                                         ErrorResult& aError) {
+  if (mShutdown) {
+    return 0;
+  }
+
+  int32_t handle = ++mFrameRequestCallbackCounter;
+
+  mFrameRequestCallbacks.AppendElement(XRFrameRequest(aCallback, handle));
+
+  return handle;
+}
+
+void XRSession::CancelAnimationFrame(int32_t aHandle, ErrorResult& aError) {
+  mFrameRequestCallbacks.RemoveElementSorted(aHandle);
+}
+
+void XRSession::Shutdown() {
+  mShutdown = true;
+  ExitPresentInternal();
+  mViewerPosePool.Clear();
+  mViewerPosePoolIndex = 0;
+  mFramePool.Clear();
+  mFramePoolIndex = 0;
+  mActiveRenderState = nullptr;
+  mPendingRenderState = nullptr;
+  mFrameRequestCallbacks.Clear();
+
+  // Unregister from nsRefreshObserver
+  if (mRefreshDriver) {
+    mRefreshDriver->RemoveRefreshObserver(this, FlushType::Display);
+    mRefreshDriver = nullptr;
+  }
+}
+
+void XRSession::ExitPresentInternal() {
+  if (mInputSources) {
+    mInputSources->Clear(this);
+  }
+  if (mDisplayClient) {
+    mDisplayClient->SessionEnded(this);
+  }
+
+  if (mXRSystem) {
+    mXRSystem->SessionEnded(this);
+  }
+
+  if (mActiveRenderState) {
+    mActiveRenderState->SessionEnded();
+  }
+
+  if (mPendingRenderState) {
+    mPendingRenderState->SessionEnded();
+  }
+
+  mDisplayPresentation = nullptr;
+  if (!mEnded) {
+    mEnded = true;
+
+    XRSessionEventInit init;
+    init.mBubbles = false;
+    init.mCancelable = false;
+    init.mSession = this;
+    RefPtr<XRSessionEvent> event =
+        XRSessionEvent::Constructor(this, u"end"_ns, init);
+
+    event->SetTrusted(true);
+    this->DispatchEvent(*event);
+  }
+}
+
+void XRSession::DisconnectFromOwner() {
+  MOZ_ASSERT(NS_IsMainThread());
+  Shutdown();
+  DOMEventTargetHelper::DisconnectFromOwner();
+}
+
+void XRSession::LastRelease() {
+  // We don't want to wait for the GC to free up the presentation
+  // for use in other documents, so we do this in LastRelease().
+  Shutdown();
+}
+
+RefPtr<XRViewerPose> XRSession::PooledViewerPose(
+    const gfx::Matrix4x4Double& aTransform, bool aEmulatedPosition) {
+  RefPtr<XRViewerPose> pose;
+  if (mViewerPosePool.Length() > mViewerPosePoolIndex) {
+    pose = mViewerPosePool.ElementAt(mViewerPosePoolIndex);
+    pose->Transform()->Update(aTransform);
+    pose->SetEmulatedPosition(aEmulatedPosition);
+  } else {
+    RefPtr<XRRigidTransform> transform = new XRRigidTransform(this, aTransform);
+    nsTArray<RefPtr<XRView>> views;
+    if (IsImmersive()) {
+      views.AppendElement(new XRView(GetParentObject(), XREye::Left));
+      views.AppendElement(new XRView(GetParentObject(), XREye::Right));
+    } else {
+      views.AppendElement(new XRView(GetParentObject(), XREye::None));
+    }
+    pose = new XRViewerPose(this, transform, aEmulatedPosition, views);
+    mViewerPosePool.AppendElement(pose);
+  }
+
+  mViewerPosePoolIndex++;
+  if (mViewerPosePoolIndex >= kMaxPoolSize) {
+    mViewerPosePoolIndex = 0;
+  }
+
+  return pose;
+}
+
+RefPtr<XRFrame> XRSession::PooledFrame() {
+  RefPtr<XRFrame> frame;
+  if (mFramePool.Length() > mFramePoolIndex) {
+    frame = mFramePool.ElementAt(mFramePoolIndex);
+  } else {
+    frame = new XRFrame(GetParentObject(), this);
+    mFramePool.AppendElement(frame);
+  }
+
+  return frame;
+}
+
+}  // namespace dom
+}  // namespace mozilla