--- a/Framework/Scene2DViewport/EditAngleMeasureTracker.cpp	Wed Mar 04 09:44:34 2020 +0100
+++ b/Framework/Scene2DViewport/EditAngleMeasureTracker.cpp	Wed Mar 04 09:45:38 2020 +0100
@@ -27,21 +27,18 @@
 {
   EditAngleMeasureTracker::EditAngleMeasureTracker(
     boost::shared_ptr<MeasureTool>  measureTool,
-    boost::weak_ptr<ViewportController> controllerW,
+    IViewport& viewport,
     const PointerEvent& e)
-    : EditMeasureTracker(controllerW, e)
+    : EditMeasureTracker(viewport, e)
   {
     ScenePoint2D scenePos = e.GetMainPosition();
-
-    boost::shared_ptr<ViewportController> controller = controllerW_.lock();
-    if (controller)
     {
-      scenePos = e.GetMainPosition().Apply(controller->GetScene().GetCanvasToSceneTransform());
+      std::unique_ptr<IViewport::ILock> lock(viewport_.Lock());
+      ViewportController& controller = lock->GetController();
+      scenePos = e.GetMainPosition().Apply(controller.GetScene().GetCanvasToSceneTransform());
     }
-
     modifiedZone_ = dynamic_cast<AngleMeasureTool&>(*measureTool).AngleHitTest(scenePos);
-
-    command_.reset(new EditAngleMeasureCommand(measureTool, controllerW));
+    command_.reset(new EditAngleMeasureCommand(measureTool, viewport));
   }
 
   EditAngleMeasureTracker::~EditAngleMeasureTracker()
@@ -51,54 +48,54 @@
 
   void EditAngleMeasureTracker::PointerMove(const PointerEvent& e)
   {
-    boost::shared_ptr<ViewportController> controller = controllerW_.lock();
-    if (controller)
-    {
-      ScenePoint2D scenePos = e.GetMainPosition().Apply(
-        controller->GetScene().GetCanvasToSceneTransform());
+    std::unique_ptr<IViewport::ILock> lock(viewport_.Lock());
+    ViewportController& controller = lock->GetController();
+    Scene2D& scene = controller.GetScene();
+
+    ScenePoint2D scenePos = e.GetMainPosition().Apply(
+      scene.GetCanvasToSceneTransform());
 
-      ScenePoint2D delta = scenePos - GetOriginalClickPosition();
+    ScenePoint2D delta = scenePos - GetOriginalClickPosition();
+
+    boost::shared_ptr<AngleMeasureToolMemento> memento =
+      boost::dynamic_pointer_cast<AngleMeasureToolMemento>(command_->mementoOriginal_);
+
+    ORTHANC_ASSERT(memento.get() != NULL);
 
-      boost::shared_ptr<AngleMeasureToolMemento> memento =
-        boost::dynamic_pointer_cast<AngleMeasureToolMemento>(command_->mementoOriginal_);
-
-      ORTHANC_ASSERT(memento.get() != NULL);
-
-      switch (modifiedZone_)
+    switch (modifiedZone_)
+    {
+      case AngleMeasureTool::AngleHighlightArea_Center:
+      {
+        ScenePoint2D newCenter = memento->center_ + delta;
+        GetCommand()->SetCenter(newCenter);
+      }
+      break;
+      case AngleMeasureTool::AngleHighlightArea_Side1:
+      case AngleMeasureTool::AngleHighlightArea_Side2:
       {
-        case AngleMeasureTool::AngleHighlightArea_Center:
-        {
-          ScenePoint2D newCenter = memento->center_ + delta;
-          GetCommand()->SetCenter(newCenter);
-        }
+        ScenePoint2D newCenter = memento->center_ + delta;
+        ScenePoint2D newSide1End = memento->side1End_ + delta;
+        ScenePoint2D newSide2End = memento->side2End_ + delta;
+        GetCommand()->SetCenter(newCenter);
+        GetCommand()->SetSide1End(newSide1End);
+        GetCommand()->SetSide2End(newSide2End);
+      }
+      break;
+      case AngleMeasureTool::AngleHighlightArea_Side1End:
+      {
+        ScenePoint2D newSide1End = memento->side1End_ + delta;
+        GetCommand()->SetSide1End(newSide1End);
+      }
+      break;
+      case AngleMeasureTool::AngleHighlightArea_Side2End:
+      {
+        ScenePoint2D newSide2End = memento->side2End_ + delta;
+        GetCommand()->SetSide2End(newSide2End);
+      }
+      break;
+      default:
+        LOG(WARNING) << "Warning: please retry the measuring tool editing operation!";
         break;
-        case AngleMeasureTool::AngleHighlightArea_Side1:
-        case AngleMeasureTool::AngleHighlightArea_Side2:
-        {
-          ScenePoint2D newCenter = memento->center_ + delta;
-          ScenePoint2D newSide1End = memento->side1End_ + delta;
-          ScenePoint2D newSide2End = memento->side2End_ + delta;
-          GetCommand()->SetCenter(newCenter);
-          GetCommand()->SetSide1End(newSide1End);
-          GetCommand()->SetSide2End(newSide2End);
-        }
-        break;
-        case AngleMeasureTool::AngleHighlightArea_Side1End:
-        {
-          ScenePoint2D newSide1End = memento->side1End_ + delta;
-          GetCommand()->SetSide1End(newSide1End);
-        }
-        break;
-        case AngleMeasureTool::AngleHighlightArea_Side2End:
-        {
-          ScenePoint2D newSide2End = memento->side2End_ + delta;
-          GetCommand()->SetSide2End(newSide2End);
-        }
-        break;
-        default:
-          LOG(WARNING) << "Warning: please retry the measuring tool editing operation!";
-          break;
-      }
     }
   }
 
@@ -119,5 +116,4 @@
     ORTHANC_ASSERT(ret.get() != NULL, "Internal error in EditAngleMeasureTracker::GetCommand()");
     return ret;
   }
-
 }