Geometry: Reimplement DOMPoint using V8 extras.

third_party/WebKit/Source/modules/vr/VRPositionState.cpp

 // 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 "modules/vr/VRPositionState.h"
 
+#include "bindings/core/v8/GeometryInterfaces.h"
+
 namespace blink {
 
 namespace {
 
-DOMPoint* vecToDomPoint(const WebVRVector4& vec, bool valid)
+ScriptValue vecToDomPoint(ScriptState* scriptState, const WebVRVector4& vec, bool valid)
 {
     if (valid)
-        return DOMPoint::create(vec.x, vec.y, vec.z, vec.w);
-    return nullptr;
+        return GeometryInterfaces::createDOMPoint(scriptState, vec.x, vec.y, vec.z, vec.w);
+    return ScriptValue::createNull(scriptState);
 }
-DOMPoint* vecToDomPoint(const WebVRVector3& vec, bool valid)
+ScriptValue vecToDomPoint(ScriptState* scriptState, const WebVRVector3& vec, bool valid)
 {
     if (valid)
-        return DOMPoint::create(vec.x, vec.y, vec.z, 1.0);
-    return nullptr;
+        return GeometryInterfaces::createDOMPoint(scriptState, vec.x, vec.y, vec.z, 1.0);
+    return ScriptValue::createNull(scriptState);
 }
 
 } // namespace
 
 VRPositionState::VRPositionState()
     : m_timeStamp(0.0)
 {
 }
 
 void VRPositionState::setState(const WebHMDSensorState &state)
 {
     m_timeStamp = state.timestamp;
-    m_orientation = vecToDomPoint(state.orientation, state.flags & WebVRSensorStateOrientation);
-    m_position = vecToDomPoint(state.position, state.flags & WebVRSensorStatePosition);
-    m_angularVelocity = vecToDomPoint(state.angularVelocity, state.flags & WebVRSensorStateAngularVelocity);
-    m_linearVelocity = vecToDomPoint(state.linearVelocity, state.flags & WebVRSensorStateLinearVelocity);
-    m_angularAcceleration = vecToDomPoint(state.angularAcceleration, state.flags & WebVRSensorStateAngularAcceleration);
-    m_linearAcceleration =  vecToDomPoint(state.linearAcceleration, state.flags & WebVRSensorStateLinearAcceleration);
+    m_state = state;
+}
+
+ScriptValue& VRPositionState::orientation(ScriptState* scriptState)
+{
+    m_orientation = vecToDomPoint(scriptState, m_state.orientation, m_state.flags & WebVRSensorStateOrientation);

[domenic, 2016/02/18 19:04:41]

This re-creates the ScriptValue every time. I think that is an observable
behavior change from JavaScript code, right? It would mean
`vrPositionState.orientation !== vrPositionState.orientation`? Which would be
bad. Why not create them in the setState method, like before?

[zino, 2016/02/22 09:51:01]

Done.

+    return m_orientation;
+}
+
+ScriptValue& VRPositionState::position(ScriptState* scriptState)
+{
+    m_position = vecToDomPoint(scriptState, m_state.position, m_state.flags & WebVRSensorStatePosition);
+    return m_position;
+}
+
+ScriptValue& VRPositionState::angularVelocity(ScriptState* scriptState)
+{
+    m_angularVelocity = vecToDomPoint(scriptState, m_state.angularVelocity, m_state.flags & WebVRSensorStateAngularVelocity);
+    return m_angularVelocity;
+}
+
+ScriptValue& VRPositionState::linearVelocity(ScriptState* scriptState)
+{
+    m_linearVelocity = vecToDomPoint(scriptState, m_state.linearVelocity, m_state.flags & WebVRSensorStateLinearVelocity);
+    return m_linearVelocity;
+}
+
+ScriptValue& VRPositionState::angularAcceleration(ScriptState* scriptState)
+{
+    m_angularAcceleration = vecToDomPoint(scriptState, m_state.angularAcceleration, m_state.flags & WebVRSensorStateAngularAcceleration);
+    return m_angularAcceleration;
+}
+
+ScriptValue& VRPositionState::linearAcceleration(ScriptState* scriptState)
+{
+    m_linearAcceleration =  vecToDomPoint(scriptState, m_state.linearAcceleration, m_state.flags & WebVRSensorStateLinearAcceleration);
+    return m_linearAcceleration;
 }
 
 DEFINE_TRACE(VRPositionState)
 {
-    visitor->trace(m_orientation);
-    visitor->trace(m_position);
-    visitor->trace(m_angularVelocity);
-    visitor->trace(m_linearVelocity);
-    visitor->trace(m_angularAcceleration);
-    visitor->trace(m_linearAcceleration);
 }
 
 } // namespace blink