WIP: working copy-no-compositor path

third_party/WebKit/Source/modules/vr/VRDisplay.h

Index: third_party/WebKit/Source/modules/vr/VRDisplay.h
diff --git a/third_party/WebKit/Source/modules/vr/VRDisplay.h b/third_party/WebKit/Source/modules/vr/VRDisplay.h
index 4927e6190e2b0ea2a6d756562d7cd094d803e1cc..82fb7a2d5938297b43156eab3ef51fc2282550a5 100644
--- a/third_party/WebKit/Source/modules/vr/VRDisplay.h
+++ b/third_party/WebKit/Source/modules/vr/VRDisplay.h
@@ -12,7 +12,6 @@
 #include "modules/vr/VRDisplayCapabilities.h"
 #include "modules/vr/VRLayer.h"
 #include "mojo/public/cpp/bindings/binding.h"
-#include "platform/Timer.h"
 #include "platform/heap/Handle.h"
 #include "public/platform/WebGraphicsContext3DProvider.h"
 #include "wtf/Forward.h"
@@ -38,10 +37,24 @@ class WebGLRenderingContextBase;
 
 enum VREye { VREyeNone, VREyeLeft, VREyeRight };
 
+class StatTracker final {
+ public:
+  StatTracker(unsigned int capacity);
+  ~StatTracker();
+  bool hasPrediction();
+  double getPrediction();
+  void add(double value);
+  void clear();
+ private:
+  unsigned int m_capacity;
+  std::list<double> m_items;
+};
+
 class VRDisplay final : public EventTargetWithInlineData,
                         public ActiveScriptWrappable<VRDisplay>,
                         public ContextLifecycleObserver,
-                        public device::mojom::blink::VRDisplayClient {
+                        public device::mojom::blink::VRDisplayClient,
+                        public NON_EXPORTED_BASE(device::mojom::blink::VRPoseClient) {
   DEFINE_WRAPPERTYPEINFO();
   USING_GARBAGE_COLLECTED_MIXIN(VRDisplay);
   USING_PRE_FINALIZER(VRDisplay, dispose);
@@ -72,7 +85,9 @@ class VRDisplay final : public EventTargetWithInlineData,
 
   int requestAnimationFrame(FrameRequestCallback*);
   void cancelAnimationFrame(int id);
-  void serviceScriptedAnimations(double monotonicAnimationStartTime);
+  void frameTick(double highResTimeMs);
+  void serviceScriptedAnimations();
+  void rescheduleAtNextTick();
 
   ScriptPromise requestPresent(ScriptState*, const HeapVector<VRLayer>& layers);
   ScriptPromise exitPresent(ScriptState*);
@@ -112,17 +127,28 @@ class VRDisplay final : public EventTargetWithInlineData,
   void updateLayerBounds();
   void disconnected();
 
+  gpu::gles2::GLES2Interface* getCompositingContext();
+
   VRController* controller();
 
  private:
-  void onFullscreenCheck(TimerBase*);
+  void submitFrameAnyContext();
+
   void onPresentComplete(bool);
+  void onSubmitFrameComplete(int32_t surfaceHandle, uint32_t poseIndex, double renderMs);
+  void onGetSurfaceHandleComplete(int32_t surfaceHandle);
+
+  void requestPose();
+  void onPoseReceived(device::mojom::blink::VRPosePtr);
 
   void onConnected();
   void onDisconnected();
 
   void OnPresentChange();
 
+  // VRPoseClient
+  void OnPoseReceived(device::mojom::blink::VRPosePtr pose) override;
+
   // VRDisplayClient
   void OnChanged(device::mojom::blink::VRDisplayInfoPtr) override;
   void OnExitPresent() override;
@@ -139,21 +165,41 @@ class VRDisplay final : public EventTargetWithInlineData,
   bool m_isConnected;
   bool m_isPresenting;
   bool m_isValidDeviceForPresenting;
+
+  double m_highResTimeMsAtLastFrameTick;
+  double m_frameTickStartMs;
+  double m_serviceStartMs;
+  double m_submitExecuteMs;
+  bool m_tickIsScheduled = false;
+
+  // Track "pending submitted frames" counter for the current output
+  // surface. Always zero while not submitting frames. Must only be
+  // changed when submitting frames to a valid surface and on its
+  // return callback if it still matches the current surface. We allow
+  // rAF processing to start if one frame is pending in post-submit,
+  // but if it's still nonzero when trying to submit a frame we defer
+  // that until the previous in-flight frame is done.
+  int m_framesPending;
+  bool m_frameWaitingToSubmit = false;
+  StatTracker m_historyPreSubmitTimeMs{7};
+  StatTracker m_historyPostSubmitTimeMs{7};
+
+  bool m_poseCallbackPending = false;
   bool m_canUpdateFramePose;
+  bool m_canSubmitFramePose;
   Member<VRDisplayCapabilities> m_capabilities;
   Member<VRStageParameters> m_stageParameters;
   Member<VREyeParameters> m_eyeParametersLeft;
   Member<VREyeParameters> m_eyeParametersRight;
   device::mojom::blink::VRPosePtr m_framePose;
   VRLayer m_layer;
+  int m_sourceWidth;
+  int m_sourceHeight;
   double m_depthNear;
   double m_depthFar;
 
   void dispose();
 
-  Timer<VRDisplay> m_fullscreenCheckTimer;
-  String m_fullscreenOrigWidth;
-  String m_fullscreenOrigHeight;
   gpu::gles2::GLES2Interface* m_contextGL;
   Member<WebGLRenderingContextBase> m_renderingContext;
 
@@ -163,11 +209,17 @@ class VRDisplay final : public EventTargetWithInlineData,
   bool m_displayBlurred;
   bool m_reenteredFullscreen;
 
+  int32_t m_surfaceHandle;
+  bool m_surfaceHandleRequested = false;
+
   device::mojom::blink::VRDisplayPtr m_display;
 
   mojo::Binding<device::mojom::blink::VRDisplayClient> m_binding;
+  mojo::Binding<device::mojom::blink::VRPoseClient> m_pose_client_binding;
 
   HeapDeque<Member<ScriptPromiseResolver>> m_pendingPresentResolvers;
+
+  std::unique_ptr<WebGraphicsContext3DProvider> m_contextProvider;
 };
 
 using VRDisplayVector = HeapVector<Member<VRDisplay>>;