Projects:ARRA:SlicerAM:Meeting20100921

On Tuesday, 21st of September 2010 Wendy, Nicole, Steve and Daniel got together to look at the current Annotation module status.

• Performance problems with multiple vtkBiDimensionalWidgets (as an example, happens with all vtkWidgets) while rotating/zooming the 3D view
  • Daniel wrote a test to place 5 vtkBiDimensionalWidgets isolated from 3D Slicer and DisplayableManagers - just pure VTK
    • The performance of this test is much better than 3D Slicer but delays are still visible
  • We took process samples on Mac OS X to find the source of these problems
    • SlicerQT with 5 vtkBiDimensionalWidgets sampling:
      

      Sample results on Slicer
    • Plain VTK (TestAnnotationWidgetsStandalone) with 5 vtkBiDimensionalWidgets sampling:
      

      Sample results on plain VTK
  • A major performance loss was identified when rendering the texts next to the widgets
    • We deactivated the text display and the rendering performance in Slicer increased dramatically
    • Possible solution: hide all texts when the 3D window is rotated etc.

• Current status of Annotation module:
  • Ruler, Bidimensional and Fiducials can be placed in 2D and 3D
    • Synchronization with MRML and among the 2D/3D views work
  • The ruler should show the dividers on a fixed scale according to millimeter or cm
  • Sometimes the placement of fiducials causes funky behavior
  • Reformated Axis or changed orientations of the SliceNodes cause problems
  • Sometimes the measurement display of rulers is not correct (f.e. a strange "4 4" display - maybe the sprintf function causes problems?)
  • Undo worked but redo crashed
  • MRML Scene Load and Save should be checked

• Next step: Hierarchy
  • API from Nicole is available in the trunk
  • We probably do not need a separate Fiducial (lite) module (TBD later)
  • There will be an invisible top hierarchy in which new annotations are added without creating a hierarchy
    • Then a new hierarchy can be added as a subset to each existing hierarchy
    • As soon as the first hierarchy gets created, the invisible top-level hierarchy will be a new visible hierarchy on the same level of the created one
  • It should be possible to pass annotation hierarchies or only one type of annotations inside a hierarchy to Node Selectors and CLI modules
  • Maybe extend the data module to provide an annotation view of the MRML tree?
    • BTW the data module crashed on drag and drop

• After hierarchy:
  • Finish up property dialog