Interaction Testing in MITK

Table of Contents

• Recording Interactions
• Limitations
• Using Interactions in Tests

Recording Interactions

To be able to record interactions activate Interaction Event Recorder in MITK-build cmake. The following table explains how to step-wise create an interaction sequence, which is necessary for developing interaction tests. The given example shows how the AddTool Segmentation Interaction Test was developed. For implementation examples refer to mitkToolInteractionTest.cpp or mitkPlanarFigureInteractionTest.cpp

Step	AddTool Segmentation Example
Load Image	MITK-Data/Pic3D.nrrd
Do not scroll image slices before recording starts	-
Activate Interaction	Click on Add in segmentation plugin
Define output filename (be careful: plugin appends interactions to existing files)	SegmentationInteractor_AddTool.xml
Start recording	Click on record symbol (red circle) in Event Recorder Plugin
Perform Interaction	Draw a segmentation in the render window
Stop recording	Click on stop symbol (red square) in Event Recorder Plugin
Save record (<interaction>.xml) to your testing environment	MITK-Data/InteractionTestData/Interactions/SegmentationInteractor_AddTool.xml
Save interaction result (Image, Surface, etc.) to your testing environment	InteractionTestData/ReferenceData/SegmentationInteractor_AddTool.nrrd

Limitations

• No VTK interactions are recorded
• Renderwindows have to stay constant during record (e.g. no resizing)
• Interactions have to follow the new Interaction concept

Using Interactions in Tests

In order to use interaction tests, the class mitk::InteractionTestHelper has to be used. The usage of this class is explained with an example of the SegmentationTool test. The TestHelper needs to know the location of the recorded interaction file. This is done by giving the filename to the constructor.

//Create test helper to initialize all necessary objects for interaction
mitk::InteractionTestHelper interactionTestHelper(GetTestDataFilePath(interactionPattern));

The InteractionTestHelper stores its own DataStorage. We want to use this DataStorage and provide all necessary DataNodes.

//Use data storage of test helper
mitk::DataStorage::Pointer dataStorage = interactionTestHelper.GetDataStorage();
 
//add images to datastorage
interactionTestHelper.AddNodeToStorage(patientImageNode);
interactionTestHelper.AddNodeToStorage(workingImageNode);

Let the InteractionTestHelper know about the relevant time step (particularly necessary with 4D images)

//set time step
interactionTestHelper.SetTimeStep(timestep);

When everything is set up, the loaded Interaction can be played back.

//Start Interaction
interactionTestHelper.PlaybackInteraction();