BUG: 3241 Fix transform not applied to volume when scene is read from…

… a file

When a scene is loaded, vtkMRMLScene::UpdateNodeReferences doesn't handle event registration.
Except for vtkCommand::ModifiedEvent, any other events need to be registered via OnNodeReferenceAdded API.
Fixes #3241

Libs/MRML/Core/Testing/CMakeLists.txt

@@ -75,6 +75,7 @@ create_test_sourcelist(Tests ${KIT}CxxTests.cxx
   vtkMRMLStorageNodeTest1.cxx
   vtkMRMLTensorVolumeNodeTest1.cxx
   vtkMRMLTransformableNodeReferenceSaveImportTest.cxx
+  vtkMRMLTransformableNodeOnNodeReferenceAddTest.cxx
   vtkMRMLTransformNodeTest1.cxx
   vtkMRMLTransformStorageNodeTest1.cxx
   vtkMRMLTransformableNodeTest1.cxx
@@ -171,6 +172,7 @@ simple_test( vtkMRMLStorableNodeTest1 )
 simple_test( vtkMRMLStorageNodeTest1 )
 simple_test( vtkMRMLTensorVolumeNodeTest1 )
 simple_test( vtkMRMLTransformableNodeReferenceSaveImportTest )
+simple_test( vtkMRMLTransformableNodeOnNodeReferenceAddTest )
 simple_test( vtkMRMLTransformableNodeTest1 )
 simple_test( vtkMRMLTransformNodeTest1 )
 simple_test( vtkMRMLTransformStorageNodeTest1 )

Libs/MRML/Core/Testing/vtkMRMLTransformableNodeOnNodeReferenceAddTest.cxx

@@ -0,0 +1,127 @@
+/*=auto=========================================================================
+
+  Program: 3D Slicer
+
+  Copyright (c) Kitware Inc.
+
+  See COPYRIGHT.txt
+  or http://www.slicer.org/copyright/copyright.txt for details.
+
+  Unless required by applicable law or agreed to in writing, software
+  distributed under the License is distributed on an "AS IS" BASIS,
+  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  See the License for the specific language governing permissions and
+  limitations under the License.
+
+  This file was originally developed by Yuzheng Zhou, Kitware Inc.
+  and was partially funded by NIH grant 3P41RR013218-12S1
+
+=========================================================================auto=*/
+
+// MRML includes
+#include "vtkMRMLCoreTestingMacros.h"
+#include "vtkMRMLLinearTransformNode.h"
+#include "vtkMRMLTransformableNode.h"
+#include "vtkMRMLScalarVolumeNode.h"
+#include "vtkMRMLScene.h"
+
+// VTK includes
+#include <vtkGeneralTransform.h>
+#include <vtkNew.h>
+#include <vtkSmartPointer.h>
+
+namespace
+{
+
+void populateScene(vtkMRMLScene* scene);
+
+} // end of anonymous namespace
+
+//---------------------------------------------------------------------------
+int vtkMRMLTransformableNodeOnNodeReferenceAddTest(int , char * [] )
+{
+  // Save a scene containing a viewnode and a sceneview node.
+  vtkNew<vtkMRMLScene> scene;
+  populateScene(scene.GetPointer());
+
+  scene->SetSaveToXMLString(1);
+  scene->Commit();
+  std::string xmlScene = scene->GetSceneXMLString();
+  std::cout << xmlScene << std::endl;
+
+  // Load the saved scene
+  vtkNew<vtkMRMLScene> scene2;
+
+  scene2->SetLoadFromXMLString(1);
+  scene2->SetSceneXMLString(xmlScene);
+  scene2->Import();
+
+  // Check transform node IDs
+  vtkMRMLNode* transformNode =
+    scene2->GetNthNodeByClass(0, "vtkMRMLLinearTransformNode");
+  if (!transformNode || strcmp(transformNode->GetID(), "vtkMRMLLinearTransformNode1") != 0)
+    {
+    std::cerr << __LINE__ << ": import failed." << std::endl
+              << "    transform node ID is " << transformNode->GetID()
+              << " instead of vtkMRMLLinearTransformNode1." << std::endl;
+
+    return EXIT_FAILURE;
+    }
+
+  // Check references
+  vtkMRMLTransformableNode* trnsformableNode =
+    vtkMRMLTransformableNode::SafeDownCast(scene2->GetNthNodeByClass(0, "vtkMRMLTransformableNode"));
+
+  if (strcmp(trnsformableNode->GetTransformNodeID(),
+             transformNode->GetID()) != 0)
+    {
+    std::cerr << __LINE__ << ": import failed." << std::endl
+              << "    Transformable node references are not updated. "
+              << "Transform node ID reference is "
+              << trnsformableNode->GetTransformNodeID()
+              << " instead of " << transformNode->GetID() << std::endl;
+    return EXIT_FAILURE;
+    }
+
+  // Test vtkMRMLTransformableNode::OnNodeReferenceAdded()
+  vtkMRMLLinearTransformNode* linearTransformNode = vtkMRMLLinearTransformNode::SafeDownCast(scene2->GetNthNodeByClass(0, "vtkMRMLLinearTransformNode"));
+  vtkMRMLScalarVolumeNode* volumeNode = vtkMRMLScalarVolumeNode::SafeDownCast(scene2->GetNthNodeByClass(0, "vtkMRMLScalarVolumeNode"));
+  vtkNew<vtkMRMLNodeCallback> callback;
+  volumeNode->AddObserver(vtkCommand::AnyEvent, callback.GetPointer());
+
+  linearTransformNode->GetMatrixTransformToParent()->Modified();
+  if (!callback->GetErrorString().empty() ||
+      callback->GetNumberOfModified() != 0 ||
+      callback->GetNumberOfEvents(vtkMRMLTransformNode::TransformModifiedEvent) != 1)
+    {
+    std::cerr << "vtkMRMLTransformableNode::OnNodeReferenceAdded failed."
+              << callback->GetErrorString().c_str() << " "
+              << "Number of ModifiedEvent: " << callback->GetNumberOfModified() << " "
+              << "Number of TransformModifiedEvent: "
+              << callback->GetNumberOfEvents(vtkMRMLTransformNode::TransformModifiedEvent)
+              << std::endl;
+    return EXIT_FAILURE;
+    }
+  callback->ResetNumberOfEvents();
+  return EXIT_SUCCESS;
+}
+
+namespace
+{
+
+//---------------------------------------------------------------------------
+void populateScene(vtkMRMLScene* scene)
+{
+
+  vtkNew<vtkMRMLScalarVolumeNode> transformableableNode;
+  scene->AddNode(transformableableNode.GetPointer());
+
+  vtkNew<vtkMRMLLinearTransformNode> transformNode;
+  scene->AddNode(transformNode.GetPointer());
+
+  transformableableNode->SetAndObserveTransformNodeID(transformNode->GetID());
+
+}
+
+
+}

Libs/MRML/Core/vtkMRMLTransformableNode.cxx

@@ -13,6 +13,7 @@ Version:   $Revision: 1.14 $
 =========================================================================auto=*/
 
 // MRML includes
+#include "vtkEventBroker.h"
 #include "vtkMRMLLinearTransformNode.h"
 #include "vtkMRMLScene.h"
 
@@ -137,6 +138,22 @@ void vtkMRMLTransformableNode::SetAndObserveTransformNodeID(const char *transfor
   this->InvokeEvent(vtkMRMLTransformableNode::TransformModifiedEvent, NULL);
 }
 
+//----------------------------------------------------------------------------
+void vtkMRMLTransformableNode::OnNodeReferenceAdded(vtkMRMLNodeReference *reference)
+{
+  Superclass::OnNodeReferenceAdded(reference);
+
+  // When a scene is loaded, vtkMRMLScene::UpdateNodeReferences doesn't handle
+  // event registration. Except for vtkCommand::ModifiedEvent, any other events
+  // need to be registered via OnNodeReferenceAdded API.
+  if (std::string(reference->GetReferenceRole()) == this->GetTransformNodeReferenceRole()
+     && reference->ReferencedNode && reference->ReferencingNode)
+    {
+    vtkEventBroker::GetInstance()->AddObservation(reference->ReferencedNode,
+      vtkMRMLTransformableNode::TransformModifiedEvent, reference->ReferencingNode, this->MRMLCallbackCommand);
+    }
+}
+
 //---------------------------------------------------------------------------
 void vtkMRMLTransformableNode::ProcessMRMLEvents ( vtkObject *caller,
                                                   unsigned long event, 

Libs/MRML/Core/vtkMRMLTransformableNode.h

@@ -105,6 +105,9 @@ class VTK_MRML_EXPORT vtkMRMLTransformableNode : public vtkMRMLNode
   virtual const char* GetTransformNodeReferenceRole();
   virtual const char* GetTransformNodeReferenceMRMLAttributeName();
 
+  /// Called when a node reference ID is added (list size increased).
+  virtual void OnNodeReferenceAdded(vtkMRMLNodeReference *reference);
+
 private:
   char* TransformNodeIDInternal;
   vtkSetStringMacro(TransformNodeIDInternal);