User:Barre/TODO

Training Event in Germany

Notes from a session with Ron, important items to address to improve Slicer3 usability.

• Save Data: how can one save a data file as a specific/different ITK file format. ITK uses a IO plugin framework to support new file formats: is there a way to find the list of file formats supported by ITK at run-time.
  • I (Seb) to check with Luis
    [UPDATE] see ImageFileReader<...>::GenerateOutputInformation, BUT every IO file/reader need to expose the list of file extensions it can read and write. Luis is on it, to be added 3.8 end of July. Luis is fast, it's in the CVS, and examplified in itkImageIOFileNameExtensionsTests.cxx

• Save Data: the "Save" dialog in general is very confusing and buggy. The "Save All" and "Save None" button are mislabelled since they don't perform any save. Saving data to a new file format requires the user to double-click in the file name and manually change the file extension (provided that this extension is known to the user). Changing the data directory does not update the data locations in the multicolumn list (it does if you change the data directory twice). Changing the scene directory has no impact on the data directory.
  • I (Seb) suggest that the "Save All/None" should be something like "Mark all for save", "Mark none for save". A button should be placed next to each data filename/location to quickly switch to a new file type (depending on what ITK can save to at run-time). The dialog is large, we have room to put a help string/label that explains a little more how the whole dialog works. Changing the data directory should update the location of each data entry in the multicolumn list correctly. A button should be added to quickly set the data directory to match the scene directory (it should not be automatic though).

• Font Size: the font is definitely too small for the "Modules" menubutton or the filename label in any of the Red/Yellow/Green slice viewports. The "View -> Font Size" menu does not report the current font size.
  • My (Seb) opinion is to avoid hard-coding font size as much as possible, and not let the user override either font size or font family: we can not support all the possible layout combinations, or guarantee it will all fit; let's focus instead on making sure it looks nice and fit decently with the default system font size. The label in the RYG slice viewports is cropped automatically to something likely too small, and not updated later on when the slice viewport is resized/maximized: to fix.
  • Ron: Starting with the system default font is a good idea. I have encountered many situations where it is critical to be able to change the font to larger or smaller. Having a keyboard shortcut for situations where the menu is not accessible might be a good idea too: Ctrl + and ctrl - come to mind, like in firefox.

• Progress Bar: the progress bar used while loading data has been removed because it was triggering too many "update idletasks". We still need one though.
  • Steve suggests creating an OpenGL progress bar directly inside a small renderwindow. I (Seb) checked VTK's scale/slider interaction widget to see if that would do the trick. To be investigated further with the VTK's widget guru, Will.

• Models, tree: the tree in "Models -> Hierarchy -> Model Hierarchy" may be too small for some users, as it gets more and more crowded.
  • My (Seb) opinion is that we can't have it resize automatically because who knows how tall it could be, and it would push everything down. Ron is OK to have an option to do it manually, so I plan to add two icon/buttons to increase/decrease the height (numbe of lines) of the tree, say add 15 more lines, and double the size, etc. I wish we could just "drag" the whole tree frame to a new size, like expanding a window, but that's just too hard (or impossible) to implement with this Tk widget.
    [UPDATE] vtkKWTreeWithScrollbars has now a ResizeButtonsVisibility flag that is set for the models and MRML tree, and allow for two small resize buttons to be used to resize a tree.

• Models, tree: the tree in "Models -> Hierarchy -> Model Hierarchy" is not as intuitive as the previous UI found in Slicer2; for each model, one could check/uncheck the visibility and change the opacity using controls placed directly next to the model's name (i.e. on the same row). The model name/label itself would use a background color matching the color used to display the model in the 3D view, a nice hint. The tree used in Slicer3 does not do nearly as much, i.e. the user has to select a node then change its visibily using a checkbutton placed in a different frame below the tree (note that the visibility and color can be changed quickly though, by using a popup menu by right-clicking on the tree leaf).
  • I (Seb) had several discussion about this item with Alex, and I'm still not sure why this can't be done technically by adding custom widgets next to the label name for each leaf in the tree, but I will have a look at it again.
    [UPDATE] Given the size of the testing scene (say, 200 elements), the multicolumn widget would be too slow if each row had a label, a color button, a visibility button, etc., and the indentation would be a ugly hack. The tree widget does support custom widgets per row, but not in separate columns: they would be misaligned (either on the left or right of a leaf label). It seems we need the TkTreeCtrl widget which was added last year when this problem was raised already; Seb to create a C++ class around this monster library and expose only the methods we need for this very specific problem; it will take some time, since TkTreeCtrl is the most complex Tcl/Tk widget to be found in KWWidgets so far.