# Development

**URL:** https://discourse.slicer.org/c/dev/5.md?no_subcategories=false&page=67

[Latest](https://discourse.slicer.org/latest.md) · [Categories](https://discourse.slicer.org/categories.md) · [Tags](https://discourse.slicer.org/tags.md)

**Page:** 68

---

## [Rebuilding custom loadable extension that is part of SlicerCAT](https://discourse.slicer.org/t/rebuilding-custom-loadable-extension-that-is-part-of-slicercat/19942)

<div class="topic-metadata">

**Author:** [@keri](https://discourse.slicer.org/u/keri)\
**Replies:** 1\
**Last updated:** [October 1, 2021, 4:18am UTC](https://discourse.slicer.org/t/rebuilding-custom-loadable-extension-that-is-part-of-slicercat/19942 "2021-10-01T04:18:03Z")

</div>

Hi, I’m working on loadable extension and I after successively built SlicerCAT I want to edit my extension source code and rebuild it. The extension is added to the SlicerCAT via FetchContent\_Populate. Then I can see …

---

## [Custom qMRMLSliceWidget and segment editor](https://discourse.slicer.org/t/custom-qmrmlslicewidget-and-segment-editor/19771)

<div class="topic-metadata">

**Author:** [@giovform](https://discourse.slicer.org/u/giovform)\
**Replies:** 15\
**Last updated:** [October 1, 2021, 2:22am UTC](https://discourse.slicer.org/t/custom-qmrmlslicewidget-and-segment-editor/19771 "2021-10-01T02:22:35Z")

</div>

Hello, this code from the script repository creates a slice view widget in a separate window: https://slicer.readthedocs.io/en/latest/developer\_guide/script\_repository.html#show-a-slice-view-outside-the-view-layout The…

---

## [Module 'PythonQt.qSlicerMarkupsModuleWidgets' has no attribute 'qMRMLMarkupsROIWidget'?](https://discourse.slicer.org/t/module-pythonqt-qslicermarkupsmodulewidgets-has-no-attribute-qmrmlmarkupsroiwidget/19675)

<div class="topic-metadata">

**Author:** [@jumbojing](https://discourse.slicer.org/u/jumbojing)\
**Replies:** 9\
**Last updated:** [September 30, 2021, 7:42pm UTC](https://discourse.slicer.org/t/module-pythonqt-qslicermarkupsmodulewidgets-has-no-attribute-qmrmlmarkupsroiwidget/19675 "2021-09-30T19:42:43Z")

</div>

Why?howto use qMRMLMarkupsROIWidget by python? \[CRITICAL\]\[Stream\] 15.09.2021 04:43:02 (unknown:0) - AttributeError: module ‘PythonQt.qSlicerMarkupsModuleWidgets’ has no attribute ‘qMRMLMarkupsROIWidget’

---

## ["Download and install extension" snippet thows exception](https://discourse.slicer.org/t/download-and-install-extension-snippet-thows-exception/19849)

<div class="topic-metadata">

**Author:** [@rbumm](https://discourse.slicer.org/u/rbumm)\
**Replies:** 12\
**Last updated:** [September 30, 2021, 6:05pm UTC](https://discourse.slicer.org/t/download-and-install-extension-snippet-thows-exception/19849 "2021-09-30T18:05:58Z")

</div>

Windows Slicer 4.13 The script repository snippet “Download and install an extension” throws a “Key error: ‘item\_id’” exception when used in Slicer 4.13 Has anything changed ? Thank you.

---

## [Superbuild extension builds failed when Python was installed - good solution?](https://discourse.slicer.org/t/superbuild-extension-builds-failed-when-python-was-installed-good-solution/19938)

<div class="topic-metadata">

**Author:** [@cpinter](https://discourse.slicer.org/u/cpinter)\
**Replies:** 2\
**Last updated:** [September 30, 2021, 4:55pm UTC](https://discourse.slicer.org/t/superbuild-extension-builds-failed-when-python-was-installed-good-solution/19938 "2021-09-30T16:55:03Z")

</div>

Hi all, I could not build first SlicerRT then SlicerOpenIGTLink today, and it seemed that the reason was a custom Python being installed on my Windows machine. See Plastimatch build fails · Issue #198 · SlicerRt/SlicerR…

---

## [Python package in installed version of slicer](https://discourse.slicer.org/t/python-package-in-installed-version-of-slicer/19937)

<div class="topic-metadata">

**Author:** [@riep](https://discourse.slicer.org/u/riep)\
**Replies:** 3\
**Last updated:** [September 30, 2021, 4:30pm UTC](https://discourse.slicer.org/t/python-package-in-installed-version-of-slicer/19937 "2021-09-30T16:30:48Z")

</div>

Hi everyone, We are working on a slicelet on Slicer v4.11.20210226. We are installing a library call weasyprint during compilation time. Everything is working fine in development environment. However, when we generate t…

---

## ['vtkSlicerMarkupsModuleMRML.vtkMRMLMarkupsROINode' has no len()](https://discourse.slicer.org/t/vtkslicermarkupsmodulemrml-vtkmrmlmarkupsroinode-has-no-len/19903)

<div class="topic-metadata">

**Author:** [@jumbojing](https://discourse.slicer.org/u/jumbojing)\
**Replies:** 5\
**Last updated:** [September 29, 2021, 6:53pm UTC](https://discourse.slicer.org/t/vtkslicermarkupsmodulemrml-vtkmrmlmarkupsroinode-has-no-len/19903 "2021-09-29T18:53:35Z")

</div>

File "/Applications/Slice98.app/Contents/bin/Python/slicer/util.py", line 1307, in getNode nodes = getNodes(pattern, scene) File "/Applications/Slice98.app/Contents/bin/Python/slicer/util.py", line 1290, in getNo…

---

## [Couldn't Reload, what's wrong](https://discourse.slicer.org/t/couldnt-reload-whats-wrong/19893)

<div class="topic-metadata">

**Author:** [@jumbojing](https://discourse.slicer.org/u/jumbojing)\
**Replies:** 3\
**Last updated:** [September 29, 2021, 6:52pm UTC](https://discourse.slicer.org/t/couldnt-reload-whats-wrong/19893 "2021-09-29T18:52:06Z")

</div>

\[CRITICAL\]\[Stream\] 28.09.2021 18:24:37 \[\] (unknown:0) - Traceback (most recent call last): \[CRITICAL\]\[Stream\] 28.09.2021 18:24:37 \[\] (unknown:0) - File "/Applications/Slice98.app/Contents/bin/Python/slicer/ScriptedLoad…

---

## [The Slice Focus Fun seems still perfect](https://discourse.slicer.org/t/the-slice-focus-fun-seems-still-perfect/19909)

<div class="topic-metadata">

**Author:** [@jumbojing](https://discourse.slicer.org/u/jumbojing)\
**Replies:** 1\
**Last updated:** [September 29, 2021, 10:49am UTC](https://discourse.slicer.org/t/the-slice-focus-fun-seems-still-perfect/19909 "2021-09-29T10:49:44Z")

</div>

\# ### P4SliceFocus # - \[\[P4SliceFocus\]\] # - From: \[Set slice position and orientation from 3 markup fiducials\](https://slicer.readthedocs.io/en/latest/developer\_guide/script\_repository.html#set-slice-position-and-orient…

---

## [Failed to build in Ubuntu 20.04 (Qt-5.12.8)](https://discourse.slicer.org/t/failed-to-build-in-ubuntu-20-04-qt-5-12-8/19811)

<div class="topic-metadata">

**Author:** [@ZakiaKhatun](https://discourse.slicer.org/u/ZakiaKhatun)\
**Replies:** 9\
**Last updated:** [September 28, 2021, 1:31pm UTC](https://discourse.slicer.org/t/failed-to-build-in-ubuntu-20-04-qt-5-12-8/19811 "2021-09-28T13:31:15Z")

</div>

Dear concern, While trying to build Slicer in Ubuntu 20.04 following the instructions mentioned, (13 hours later) I got the following error message (make: Target ‘default\_target’ not remade because of errors. Please fin…

---

## [How to disable Crosshair with mouse drag&drop?](https://discourse.slicer.org/t/how-to-disable-crosshair-with-mouse-drag-drop/19892)

<div class="topic-metadata">

**Author:** [@jumbojing](https://discourse.slicer.org/u/jumbojing)\
**Replies:** 2\
**Last updated:** [September 28, 2021, 1:27pm UTC](https://discourse.slicer.org/t/how-to-disable-crosshair-with-mouse-drag-drop/19892 "2021-09-28T13:27:08Z")

</div>

在我的插件中,只需要(opt+cmd)旋转crosshair,(shift)选择定位这些操作,可是这个mouse drag&drop会干扰我的有效操作,我想禁用,该怎么做? In my plug-in, I only need (Opt+cmd)+drag to rotate the crosshair and (Shift)+click to select the location, but this mouse drag&dro…

---

## [Real time ultrasound images display using vtkImageImport](https://discourse.slicer.org/t/real-time-ultrasound-images-display-using-vtkimageimport/538)

<div class="topic-metadata">

**Author:** [@Tiffas](https://discourse.slicer.org/u/Tiffas)\
**Replies:** 5\
**Last updated:** [September 28, 2021, 12:07pm UTC](https://discourse.slicer.org/t/real-time-ultrasound-images-display-using-vtkimageimport/538 "2021-09-28T12:07:13Z")

</div>

Operating system: Ubuntu 16.04 LTS Slicer version: 4.7.0-2016-11-08 r25516 Expected behavior: Real time ultrasound images display. Actual behavior: Slicer crashes when the Volumes module is selected. Hi, I have an u…

---

## [Annotation in volume rendering](https://discourse.slicer.org/t/annotation-in-volume-rendering/19869)

<div class="topic-metadata">

**Author:** [@riep](https://discourse.slicer.org/u/riep)\
**Replies:** 6\
**Last updated:** [September 27, 2021, 10:26am UTC](https://discourse.slicer.org/t/annotation-in-volume-rendering/19869 "2021-09-27T10:26:24Z")

</div>

Hi everyone, I am working on a python scripted slicelet where I instantiate/modify several Markups planes and vtk cubes based on several QSpinBox values (volume rendering is active). The process on the signal onValueCha…

---

## [Issue with Margin Effect margin value sign](https://discourse.slicer.org/t/issue-with-margin-effect-margin-value-sign/19861)

<div class="topic-metadata">

**Author:** [@Sharada](https://discourse.slicer.org/u/Sharada)\
**Replies:** 3\
**Last updated:** [September 27, 2021, 3:16am UTC](https://discourse.slicer.org/t/issue-with-margin-effect-margin-value-sign/19861 "2021-09-27T03:16:44Z")

</div>

Hello, I have a weird issue with the margin effect in the Segmentation module. The mask seems to grow when I try to shrink it. I apologize in advance if there might be a simple oversight. Code: slicer.app.processEvent…

---

## [TetrahedralMeshGenerator crash](https://discourse.slicer.org/t/tetrahedralmeshgenerator-crash/19860)

<div class="topic-metadata">

**Author:** [@Saima](https://discourse.slicer.org/u/Saima)\
**Replies:** 3\
**Last updated:** [September 26, 2021, 4:49am UTC](https://discourse.slicer.org/t/tetrahedralmeshgenerator-crash/19860 "2021-09-26T04:49:57Z")

</div>

Hi Andras, Its strange, it didnt run at all and the slicer crashes. ’ Here is what it says: Switch to module: “Welcome” Switch to module: “TetrahedralMeshGenerator” QXcbConnection: XCB error: 3 (BadWindow), sequen…

---

## [Show processing progress information in a module GUI](https://discourse.slicer.org/t/show-processing-progress-information-in-a-module-gui/19859)

<div class="topic-metadata">

**Author:** [@Saima](https://discourse.slicer.org/u/Saima)\
**Replies:** 0\
**Last updated:** [September 26, 2021, 4:51am UTC](https://discourse.slicer.org/t/show-processing-progress-information-in-a-module-gui/19859 "2021-09-26T04:51:15Z")

</div>

Hi andras, Do you know how can i show the processing information of the module in the module gui window. Thank s Regards, Saima Safdar

---

## [How Can I fix this bug SimpleITK (MSB8066)](https://discourse.slicer.org/t/how-can-i-fix-this-bug-simpleitk-msb8066/19850)

<div class="topic-metadata">

**Author:** [@kookoo9999](https://discourse.slicer.org/u/kookoo9999)\
**Replies:** 1\
**Last updated:** [September 26, 2021, 4:03am UTC](https://discourse.slicer.org/t/how-can-i-fix-this-bug-simpleitk-msb8066/19850 "2021-09-26T04:03:09Z")

</div>

I fixed the error of LibArchive for delete line in C:\\D\\S4R\\LibArchive\\libarchive\\archive\_read\_support\_format\_rar5.c line 74. And now, I can’t fix this error (MSB8066 , when I build the SimpleITK) I read here and I try…

---

## [In the "KEEP\_LARGEST\_ISLAND", is there a size limit for the largest island?](https://discourse.slicer.org/t/in-the-keep-largest-island-is-there-a-size-limit-for-the-largest-island/19780)

<div class="topic-metadata">

**Author:** [@jumbojing](https://discourse.slicer.org/u/jumbojing)\
**Replies:** 7\
**Last updated:** [September 25, 2021, 2:14am UTC](https://discourse.slicer.org/t/in-the-keep-largest-island-is-there-a-size-limit-for-the-largest-island/19780 "2021-09-25T02:14:15Z")

</div>

在应用KEEP\_LARGEST\_ISLAND时, 我得到了"0 island, 2 ignored", 可能是因为我"cropped volume"的太小了? When applying KEEP\_LARGEST\_ISLAND, I got “0 island, 2 ignored”. Maybe it is because my “cropped volume” is too small?

---

## [Elastix to accept a non-linear initial transform (-t0 TransformParameters.txt)](https://discourse.slicer.org/t/elastix-to-accept-a-non-linear-initial-transform-t0-transformparameters-txt/19817)

<div class="topic-metadata">

**Author:** [@Magi](https://discourse.slicer.org/u/Magi)\
**Replies:** 6\
**Last updated:** [September 24, 2021, 7:07pm UTC](https://discourse.slicer.org/t/elastix-to-accept-a-non-linear-initial-transform-t0-transformparameters-txt/19817 "2021-09-24T19:07:29Z")

</div>

Hi, in regards to the Slicer module ‘General Registration (Elastix)’… could someone please modify the elastix registration code/GUI to accept an initial transform from outside elastix? This is not a linear transform, t…

---

## [Which great god can make a plug-in that can realize the'transform' and'translate' of the geometry in "3d\_Slicer"?](https://discourse.slicer.org/t/which-great-god-can-make-a-plug-in-that-can-realize-thetransform-andtranslate-of-the-geometry-in-3d-slicer/19835)

<div class="topic-metadata">

**Author:** [@jumbojing](https://discourse.slicer.org/u/jumbojing)\
**Replies:** 1\
**Last updated:** [September 24, 2021, 8:50am UTC](https://discourse.slicer.org/t/which-great-god-can-make-a-plug-in-that-can-realize-thetransform-andtranslate-of-the-geometry-in-3d-slicer/19835 "2021-09-24T08:50:58Z")

</div>

Which great god can make a plug-in that can realize the’transform’ and’translate’ of the geometry in “3d\_Slicer”?

---

## [Building an extension](https://discourse.slicer.org/t/building-an-extension/19823)

<div class="topic-metadata">

**Author:** [@Aamir\_Khan](https://discourse.slicer.org/u/Aamir_Khan)\
**Replies:** 4\
**Last updated:** [September 23, 2021, 9:41pm UTC](https://discourse.slicer.org/t/building-an-extension/19823 "2021-09-23T21:41:52Z")

</div>

Hi, I am trying to develop an extension. Here, I would select three fiducial points and on pressing an apply button the volume would transform to a customized coordinate frame. I have developed the logic and it works as…

---

## [What's wrong with this code of 'INTERSECT' to 2 segmentations?](https://discourse.slicer.org/t/whats-wrong-with-this-code-of-intersect-to-2-segmentations/19822)

<div class="topic-metadata">

**Author:** [@jumbojing](https://discourse.slicer.org/u/jumbojing)\
**Replies:** 1\
**Last updated:** [September 23, 2021, 5:13pm UTC](https://discourse.slicer.org/t/whats-wrong-with-this-code-of-intersect-to-2-segmentations/19822 "2021-09-23T17:13:25Z")

</div>

我想做2个Segmentation的交集…遇到了问题…大神帮帮我 I want to use python to do the intersection of 2 Segmentations…I have a problem…Help me please seg = slicer.util.getNode("segment") # Cyl = Logic.p2pCyl(P0,P1,radius=1) modNode = get…

---

## [Extensions do build but fail to upload to midas](https://discourse.slicer.org/t/extensions-do-build-but-fail-to-upload-to-midas/19803)

<div class="topic-metadata">

**Author:** [@Alex\_Vergara](https://discourse.slicer.org/u/Alex_Vergara)\
**Replies:** 8\
**Last updated:** [September 23, 2021, 1:31pm UTC](https://discourse.slicer.org/t/extensions-do-build-but-fail-to-upload-to-midas/19803 "2021-09-23T13:31:25Z")

</div>

Something weird is being happening lately, my extension is succesfully built but not uploaded to midas, see CDash Is this a fake report? Since I can see the extension still available. Perhaps an old version that did not…

---

## [Update Slicer's icon set](https://discourse.slicer.org/t/update-slicers-icon-set/12483)

<div class="topic-metadata">

**Author:** [@lassoan](https://discourse.slicer.org/u/lassoan)\
**Replies:** 13\
**Last updated:** [September 22, 2021, 11:55pm UTC](https://discourse.slicer.org/t/update-slicers-icon-set/12483 "2021-09-22T23:55:52Z")

</div>

We are making great progress with supporting dark mode in Slicer (see here). However, our current icon set holds us back, as many of the icons are not very well visible/recognizable over dark background. Refreshing our i…

---

## [How to judge whether a point in a space is in the ROI?](https://discourse.slicer.org/t/how-to-judge-whether-a-point-in-a-space-is-in-the-roi/19795)

<div class="topic-metadata">

**Author:** [@jumbojing](https://discourse.slicer.org/u/jumbojing)\
**Replies:** 5\
**Last updated:** [September 22, 2021, 9:43pm UTC](https://discourse.slicer.org/t/how-to-judge-whether-a-point-in-a-space-is-in-the-roi/19795 "2021-09-22T21:43:34Z")

</div>

How to judge whether a point in a space is in the ROI?

---

## [What's the different between show3D smooth and the segment's smooth?](https://discourse.slicer.org/t/whats-the-different-between-show3d-smooth-and-the-segments-smooth/19750)

<div class="topic-metadata">

**Author:** [@timeanddoctor](https://discourse.slicer.org/u/timeanddoctor)\
**Replies:** 3\
**Last updated:** [September 22, 2021, 3:58am UTC](https://discourse.slicer.org/t/whats-the-different-between-show3d-smooth-and-the-segments-smooth/19750 "2021-09-22T03:58:21Z")

</div>

I created a segment and show a well smooth 3D model with smooth factor=0.7. However, when I try to use the segment smooth(median,joint smoothing or closing) and the smooth factor=0 of show3D, the model seems very rough. …

---

## [Create non GUI module](https://discourse.slicer.org/t/create-non-gui-module/19787)

<div class="topic-metadata">

**Author:** [@keri](https://discourse.slicer.org/u/keri)\
**Replies:** 1\
**Last updated:** [September 21, 2021, 5:53pm UTC](https://discourse.slicer.org/t/create-non-gui-module/19787 "2021-09-21T17:53:38Z")

</div>

Hi, Is it possible to create non GUI loadable module? Hide it even from module menu. I used to find some information in Intertnet but can’t do that now…

---

## [How do I programmatically allow segment volumes from different segmentations to be shown in one table in the segment statistics module?](https://discourse.slicer.org/t/how-do-i-programmatically-allow-segment-volumes-from-different-segmentations-to-be-shown-in-one-table-in-the-segment-statistics-module/19725)

<div class="topic-metadata">

**Author:** [@akshay\_pillai](https://discourse.slicer.org/u/akshay_pillai)\
**Replies:** 4\
**Last updated:** [September 21, 2021, 5:46pm UTC](https://discourse.slicer.org/t/how-do-i-programmatically-allow-segment-volumes-from-different-segmentations-to-be-shown-in-one-table-in-the-segment-statistics-module/19725 "2021-09-21T17:46:51Z")

</div>

I know that we can use the segment statistics, module to get the volume of individual segments inside a segmentation in a table. How do I programmatically make it add volumes of segments in different segmentations? I wou…

---

## [Python wrapping of plastimatch](https://discourse.slicer.org/t/python-wrapping-of-plastimatch/6722)

<div class="topic-metadata">

**Author:** [@gcsharp](https://discourse.slicer.org/u/gcsharp)\
**Replies:** 10\
**Last updated:** [September 21, 2021, 9:21am UTC](https://discourse.slicer.org/t/python-wrapping-of-plastimatch/6722 "2021-09-21T09:21:25Z")

</div>

This morning I have been investigating python wrapping for plastimatch. It looks feasible to use the ITK wrapping method. Would this be a reasonable approach for eventually allowing python interaction within 3D Slicer?…

---

## [Improve recognizability of Segment Editor effects icons](https://discourse.slicer.org/t/improve-recognizability-of-segment-editor-effects-icons/19772)

<div class="topic-metadata">

**Author:** [@jamesobutler](https://discourse.slicer.org/u/jamesobutler)\
**Replies:** 7\
**Last updated:** [September 20, 2021, 11:43pm UTC](https://discourse.slicer.org/t/improve-recognizability-of-segment-editor-effects-icons/19772 "2021-09-20T23:43:19Z")

</div>

With recent optimization of the Segment Editor module GUI the segment effects are now displayed a QToolButtons with icons that do not display text with the button. Text was removed to make the buttons more compact and to…

[Previous page](https://discourse.slicer.org/c/dev/5.md?no_subcategories=false&page=66)

[Next page](https://discourse.slicer.org/c/dev/5.md?no_subcategories=false&page=68)