Changes applied in a python script propagate only to the GUI but don't get displayed

Support
1

I’m trying to write a script that applies a color gradient to a markups curve.

All the changes are visible in the GUI, but the displayed curve does not change. To change the curve I have to manually click on something in the GUi (to update it?).

This is my code

# get color table
iron = slicer.util.getFirstNodeByName("Iron")

curveNode = slicer.mrmlScene.GetFirstNodeByName("MarkupsCurve_2")
dispNode = curveNode.GetDisplayNode()
dispNode.SetActiveScalarName("PedigreeIDs")
dispNode.SetAndObserveColorNodeID(iron.GetID())
dispNode.SetScalarVisibility(1)

This is how it looks after the code is executed (the Iron color table is not applied):

image
image1272×369 26.3 KB

Then, if I e.g. click twice on the ‘Visibile:’ checkbox, the view gets updated (the Iron color table is applied):

image
image1250×341 24.9 KB

2

You can make the coloring appear like this:

iron = slicer.util.getFirstNodeByName("Iron")
curveNode = slicer.mrmlScene.GetFirstNodeByName("OC")
dispNode = curveNode.GetDisplayNode()
dispNode.SetAndObserveColorNodeID(iron.GetID())
dispNode.SetActiveScalarName("PedigreeIDs")
dispNode.SetScalarVisibility(1)
dispNode.UpdateAssignedAttribute()
dispNode.Modified()

The last two lines should not be needed (should be called automatically internally) - I’ll fix that soon in Slicer core.

3

The issue is now fixed, in Slicer Preview Releases downloaded tomorrow or later the last two lines of the script above will not be necessary anymore.