# \#vtk

**URL:** https://discourse.slicer.org/tag/vtk/27.md

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

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## [Problems with extension manager](https://discourse.slicer.org/t/problems-with-extension-manager/47030)

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**Author:** [@jaimigray](https://discourse.slicer.org/u/jaimigray)\
**Replies:** 5\
**Last updated:** [May 18, 2026, 5:21pm UTC](https://discourse.slicer.org/t/problems-with-extension-manager/47030 "2026-05-18T17:21:36Z")

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Hi team! I’m having some problems with Slicer not loading the extensions manager correctly. This is happening with newer and older versions of slicer. When I launch Slicer, it opens a separate blank window called “vtkOut…

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## [Help with IJK to LPS Conversion Mismatch When Rendering CT Volume Outside Slicer](https://discourse.slicer.org/t/help-with-ijk-to-lps-conversion-mismatch-when-rendering-ct-volume-outside-slicer/43099)

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**Author:** [@Khaleel\_Ur\_Rehman](https://discourse.slicer.org/u/Khaleel_Ur_Rehman)\
**Replies:** 2\
**Last updated:** [May 26, 2025, 7:54pm UTC](https://discourse.slicer.org/t/help-with-ijk-to-lps-conversion-mismatch-when-rendering-ct-volume-outside-slicer/43099 "2025-05-26T19:54:16Z")

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Hello Slicer Community, I’m currently working on a custom algorithm that requires rendering a CT volume in 3D using VTK (outside of Slicer). As part of this, I need to convert the CT image from IJK space to LPS (or RAS)…

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## [VTK build fails on Windows in Debug mode](https://discourse.slicer.org/t/vtk-build-fails-on-windows-in-debug-mode/42590)

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**Author:** [@ungi](https://discourse.slicer.org/u/ungi)\
**Replies:** 2\
**Last updated:** [April 20, 2025, 2:28am UTC](https://discourse.slicer.org/t/vtk-build-fails-on-windows-in-debug-mode/42590 "2025-04-20T02:28:32Z")

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Hi, I followed the Slicer build instructions today on Windows with default CMake options. The Release build went well with no errors. But in Debug mode, one project from VTK resulted in a link error. Looks like the resul…

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## [Issue with vtk.vtkCommand.HoverEvent on vtk.vtkHandleWidget](https://discourse.slicer.org/t/issue-with-vtk-vtkcommand-hoverevent-on-vtk-vtkhandlewidget/41159)

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**Author:** [@jhan1245](https://discourse.slicer.org/u/jhan1245)\
**Replies:** 0\
**Last updated:** [January 20, 2025, 7:53am UTC](https://discourse.slicer.org/t/issue-with-vtk-vtkcommand-hoverevent-on-vtk-vtkhandlewidget/41159 "2025-01-20T07:53:32Z")

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I am currently working with the vtk.vtkHandleWidget and attempting to add the vtk.vtkCommand.HoverEvent using the AddObserver method. However, it seems that the hover event is not functioning as expected. Could you prov…

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## [Show FieldData in Models](https://discourse.slicer.org/t/show-fielddata-in-models/40515)

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**Author:** [@phcerdan](https://discourse.slicer.org/u/phcerdan)\
**Replies:** 0\
**Last updated:** [December 4, 2024, 9:27pm UTC](https://discourse.slicer.org/t/show-fielddata-in-models/40515 "2024-12-04T21:27:21Z")

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The only way to pass metadata along a pipeline in VTK is with FieldData. FieldData is not associated to vertices or edges on the Mesh. Slicer has no way, up to my knowledge to show the FieldData of a vtk file. Paravie…

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## [VTK file "coloring"](https://discourse.slicer.org/t/vtk-file-coloring/40073)

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**Author:** [@Bor\_Antolic](https://discourse.slicer.org/u/Bor_Antolic)\
**Replies:** 0\
**Last updated:** [November 7, 2024, 7:07pm UTC](https://discourse.slicer.org/t/vtk-file-coloring/40073 "2024-11-07T19:07:29Z")

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With the use of model-to-model distance module I created a model that shows the thickness of left ventricular wall. I exported this file as a vtk. If I open this file in Paraview I have to always manually adjust the dat…

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## [In volume rendering, how to set the rendering result to not blur when rotating the camera](https://discourse.slicer.org/t/in-volume-rendering-how-to-set-the-rendering-result-to-not-blur-when-rotating-the-camera/39742)

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**Author:** [@dbtruong](https://discourse.slicer.org/u/dbtruong)\
**Replies:** 4\
**Last updated:** [October 21, 2024, 1:44am UTC](https://discourse.slicer.org/t/in-volume-rendering-how-to-set-the-rendering-result-to-not-blur-when-rotating-the-camera/39742 "2024-10-21T01:44:37Z")

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The question is what I want to ask. How to fix results when rendering CPU usage? Thanks a lot.

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## [MakeModelEffect not showing in segmentation editor and no vtk file](https://discourse.slicer.org/t/makemodeleffect-not-showing-in-segmentation-editor-and-no-vtk-file/38487)

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**Author:** [@radhiali](https://discourse.slicer.org/u/radhiali)\
**Replies:** 2\
**Last updated:** [September 22, 2024, 7:03pm UTC](https://discourse.slicer.org/t/makemodeleffect-not-showing-in-segmentation-editor-and-no-vtk-file/38487 "2024-09-22T19:03:53Z")

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Hi I am following some of the featured tutorials from your site and a lot of the youtube videos show a “MakeModelEffect” button in the editor. I could not find it in my version but I did find “Show 3D” button, which has…

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## [Seek advice on merge surfaces](https://discourse.slicer.org/t/seek-advice-on-merge-surfaces/37682)

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**Author:** [@Lulu](https://discourse.slicer.org/u/Lulu)\
**Replies:** 6\
**Last updated:** [August 6, 2024, 2:13am UTC](https://discourse.slicer.org/t/seek-advice-on-merge-surfaces/37682 "2024-08-06T02:13:02Z")

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I’m working on a project to reconstruct the surface of the bronchi. My idea is to generate tubes to compensate for the end loss of the model after smoothing. I generated tubes of different sizes through the centerline.…

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## [Orienting a cylinder model using vtk](https://discourse.slicer.org/t/orienting-a-cylinder-model-using-vtk/24880)

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**Author:** [@SegmentedYannig](https://discourse.slicer.org/u/SegmentedYannig)\
**Replies:** 2\
**Last updated:** [June 1, 2024, 11:37pm UTC](https://discourse.slicer.org/t/orienting-a-cylinder-model-using-vtk/24880 "2024-06-01T23:37:33Z")

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Hello, I’ve been having issues with orienting a cylinder with vtk. After applying a transformation (with vtkTransformPolyDataFilter), the model wouldn’t display anymore (the non oriented cylinder can be displayed). At fi…

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## [Add vtkVectorText programmatically](https://discourse.slicer.org/t/add-vtkvectortext-programmatically/33977)

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**Author:** [@Jeff\_Zeyl](https://discourse.slicer.org/u/Jeff_Zeyl)\
**Replies:** 4\
**Last updated:** [May 8, 2024, 7:48pm UTC](https://discourse.slicer.org/t/add-vtkvectortext-programmatically/33977 "2024-05-08T19:48:30Z")

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I would like to engrave many text models onto a skin model, programmatically, based on a set of markup control point coordinates. My current approach is to generate vtk.vtkVectorText models, set their location, and subt…

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## [Include and compile itk, vtk as an ExternalProject or Submodule](https://discourse.slicer.org/t/include-and-compile-itk-vtk-as-an-externalproject-or-submodule/35337)

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**Author:** [@weidonglian](https://discourse.slicer.org/u/weidonglian)\
**Replies:** 2\
**Last updated:** [April 7, 2024, 7:47pm UTC](https://discourse.slicer.org/t/include-and-compile-itk-vtk-as-an-externalproject-or-submodule/35337 "2024-04-07T19:47:51Z")

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In my c++ application, I need to use both itk, vtk and qt. In order to make the development reproducible without build itk/vtk as a seperate cmake project which definitely has a lot overhead. I have tried so far add itk…

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## [How to get GPU information using QT and VTK?](https://discourse.slicer.org/t/how-to-get-gpu-information-using-qt-and-vtk/35297)

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**Author:** [@BerDom.Ing](https://discourse.slicer.org/u/BerDom.Ing)\
**Replies:** 10\
**Last updated:** [April 6, 2024, 8:57pm UTC](https://discourse.slicer.org/t/how-to-get-gpu-information-using-qt-and-vtk/35297 "2024-04-06T20:57:00Z")

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I’m trying to create a method that returns the graphics card information. To do this, I’m importing “from vtk.qt.QVTKRenderWindowInteractor import QVTKRenderWindowInteractor”. def get\_graphics\_card\_info(): …

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## [Trouble Storing a certain Volume State in a Scene View](https://discourse.slicer.org/t/trouble-storing-a-certain-volume-state-in-a-scene-view/34994)

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**Author:** [@Adam-Ismaili-92](https://discourse.slicer.org/u/Adam-Ismaili-92)\
**Replies:** 0\
**Last updated:** [March 20, 2024, 7:45pm UTC](https://discourse.slicer.org/t/trouble-storing-a-certain-volume-state-in-a-scene-view/34994 "2024-03-20T19:45:46Z")

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\# Consider having defined “origin” (a 3d array point), “axis1” (a 3d array axis), “alpha” (a float) # Rotation process transform1 = vtk.vtkTransform() transform1.Translate(-origin\[0\], -origin\[1\], -origin\[2\]) transfor…

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## [Overlay model with original image in slicer](https://discourse.slicer.org/t/overlay-model-with-original-image-in-slicer/33305)

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**Author:** [@G\_Tom](https://discourse.slicer.org/u/G_Tom)\
**Replies:** 3\
**Last updated:** [December 13, 2023, 10:11pm UTC](https://discourse.slicer.org/t/overlay-model-with-original-image-in-slicer/33305 "2023-12-13T22:11:44Z")

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Hi, I have the following MWE code in slicer. I want to show the 3D grid of the image along with the image. I use the vtkExtractEdges and pass that to a vtkTubeFilter. When I visualize the result, the extracted grid is …

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## [Is there a way to have all vertices on a vtk model be markups/landmarks?](https://discourse.slicer.org/t/is-there-a-way-to-have-all-vertices-on-a-vtk-model-be-markups-landmarks/28752)

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**Author:** [@Gening\_Dong](https://discourse.slicer.org/u/Gening_Dong)\
**Replies:** 4\
**Last updated:** [November 16, 2023, 8:52am UTC](https://discourse.slicer.org/t/is-there-a-way-to-have-all-vertices-on-a-vtk-model-be-markups-landmarks/28752 "2023-11-16T08:52:55Z")

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Hi, I’m trying to match the node IDs between two vtk models. I was thinking if it’s possible to have all vertices on a vtk model be markups, so that I can directly use the vertices on the surface of the source model as …

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## [How to configure VR controls interactions in Python?](https://discourse.slicer.org/t/how-to-configure-vr-controls-interactions-in-python/29312)

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**Author:** [@guillaumarie](https://discourse.slicer.org/u/guillaumarie)\
**Replies:** 5\
**Last updated:** [November 2, 2023, 1:21pm UTC](https://discourse.slicer.org/t/how-to-configure-vr-controls-interactions-in-python/29312 "2023-11-02T13:21:25Z")

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Hi, I’m developing a 3DSlicer module using the virtual reality module and a Valve Index headset. I’m trying to configure my own controller interactions in order to: Deactivate all default VR controls Add new customiz…

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## [How to convert vtkPoints to numpy?](https://discourse.slicer.org/t/how-to-convert-vtkpoints-to-numpy/30445)

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**Author:** [@wrc](https://discourse.slicer.org/u/wrc)\
**Replies:** 1\
**Last updated:** [July 7, 2023, 8:55am UTC](https://discourse.slicer.org/t/how-to-convert-vtkpoints-to-numpy/30445 "2023-07-07T08:55:19Z")

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Hello, I want to convert vtkPoints to numpy. I used vtk.util.numpy\_support.vtk\_to\_numpy(vtkPoints) But I got File "/Applications/Slicer.app/Contents/bin/Python/vtkmodules/util/numpy\_support.py", line 220, in vtk\_to\_…

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## [Repost in support (sorry) python function vs main / crash in function but not in main](https://discourse.slicer.org/t/repost-in-support-sorry-python-function-vs-main-crash-in-function-but-not-in-main/29915)

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**Author:** [@Nicolas\_Tempier](https://discourse.slicer.org/u/Nicolas_Tempier)\
**Replies:** 3\
**Last updated:** [June 9, 2023, 1:43pm UTC](https://discourse.slicer.org/t/repost-in-support-sorry-python-function-vs-main-crash-in-function-but-not-in-main/29915 "2023-06-09T13:43:12Z")

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Hello everyone, first of all, sorry for the repost, i posted this issue in development section instead of support … i have a little problem understanding why my code crashes when i use it as a function. i want to disp…

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## [How to set VR camera position in Python?](https://discourse.slicer.org/t/how-to-set-vr-camera-position-in-python/29418)

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**Author:** [@Gianluca\_De\_Lucia](https://discourse.slicer.org/u/Gianluca_De_Lucia)\
**Replies:** 1\
**Last updated:** [May 12, 2023, 10:02am UTC](https://discourse.slicer.org/t/how-to-set-vr-camera-position-in-python/29418 "2023-05-12T10:02:15Z")

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Hi, I am trying to develop a Python script for viewing an STL file through your VR module for 3DSlicer. I need to set up the camera position, but as far I didn’t succeed. I tried with: slicer.modules.virtualreality.…

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## [SlicerLookingGlass Extension: Slicer models are stretched and distorted on the Quilt](https://discourse.slicer.org/t/slicerlookingglass-extension-slicer-models-are-stretched-and-distorted-on-the-quilt/28303)

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**Author:** [@mircat](https://discourse.slicer.org/u/mircat)\
**Replies:** 2\
**Last updated:** [March 20, 2023, 2:03pm UTC](https://discourse.slicer.org/t/slicerlookingglass-extension-slicer-models-are-stretched-and-distorted-on-the-quilt/28303 "2023-03-20T14:03:08Z")

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Hello! When generating a quilt using the SlicerLookingGlass Module, the Slicer model becomes stretched, resulting in a blurry and distorted image on the Looking Glass Portrait. See image below. I have a cube model which…

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## [Dicom to rectilinear grid vtk](https://discourse.slicer.org/t/dicom-to-rectilinear-grid-vtk/28289)

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**Author:** [@fil](https://discourse.slicer.org/u/fil)\
**Replies:** 9\
**Last updated:** [March 13, 2023, 10:11am UTC](https://discourse.slicer.org/t/dicom-to-rectilinear-grid-vtk/28289 "2023-03-13T10:11:03Z")

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How can I create rectilinear grid .vtk file from DICOM flies, please? I used to be able to do this using slicer. Any help will be much appreciated. Thank you.

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## [Slicer - Convert centerlines to a graph {V,E}](https://discourse.slicer.org/t/slicer-convert-centerlines-to-a-graph-v-e/18604)

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**Author:** [@som1197](https://discourse.slicer.org/u/som1197)\
**Replies:** 6\
**Last updated:** [November 14, 2022, 12:35pm UTC](https://discourse.slicer.org/t/slicer-convert-centerlines-to-a-graph-v-e/18604 "2022-11-14T12:35:07Z")

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Hello, I want to convert the centerline network generated from the segmentations of the Circle of Willis into a graph data structure. Currently the only way to do it in vmtk is to use the ‘vmtknetworkextraction’ class t…

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## [Error creating a module](https://discourse.slicer.org/t/error-creating-a-module/25712)

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**Author:** [@LuisaDantas](https://discourse.slicer.org/u/LuisaDantas)\
**Replies:** 15\
**Last updated:** [November 8, 2022, 2:48pm UTC](https://discourse.slicer.org/t/error-creating-a-module/25712 "2022-11-08T14:48:46Z")

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Hey, I’m following PerkLab’s Slicer bootcamp tutorial on how to create a Module for 3D Slicer. But when I try to run the code to see the changes it returns this error: ModuleNotFoundError: No module named 'vtkmodules.v…

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## [Limit computation only to current slices](https://discourse.slicer.org/t/limit-computation-only-to-current-slices/24335)

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**Author:** [@brandus1](https://discourse.slicer.org/u/brandus1)\
**Replies:** 4\
**Last updated:** [August 26, 2022, 8:45pm UTC](https://discourse.slicer.org/t/limit-computation-only-to-current-slices/24335 "2022-08-26T20:45:05Z")

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Hello, I have a 200x200x200 vtk array of 20 components (representing 10 complex numbers). I need to do a fairly heavy matrix multiplication on each set of 20 components. This needs to happen in real time as the user ch…

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## [Display VTK Wedge in Slicer as Segmentation](https://discourse.slicer.org/t/display-vtk-wedge-in-slicer-as-segmentation/24838)

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**Author:** [@connorh](https://discourse.slicer.org/u/connorh)\
**Replies:** 4\
**Last updated:** [August 23, 2022, 6:01pm UTC](https://discourse.slicer.org/t/display-vtk-wedge-in-slicer-as-segmentation/24838 "2022-08-23T18:01:43Z")

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I’m trying to split a segment based on its rotational position (e.g. only getting a 15 deg wedge of the segmentation). I’m thinking the way to do this is to create a vtkWedge shape and take its intersection with the exis…

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## [Retrieve Volume and Surface Area of a ModelNode (Surface Mesh (vtkPolyData)) - Python](https://discourse.slicer.org/t/retrieve-volume-and-surface-area-of-a-modelnode-surface-mesh-vtkpolydata-python/21556)

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**Author:** [@l.geronzi](https://discourse.slicer.org/u/l.geronzi)\
**Replies:** 4\
**Last updated:** [August 2, 2022, 2:57am UTC](https://discourse.slicer.org/t/retrieve-volume-and-surface-area-of-a-modelnode-surface-mesh-vtkpolydata-python/21556 "2022-08-02T02:57:01Z")

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Hi all, I am a beginner and I don’t have much experience with the 3DSlicer environment and vtk libraries. I have already followed the various tutorials to get started. My problem is the following. I am trying to use p…

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## [loadable module to integrate a haptic device ](https://discourse.slicer.org/t/loadable-module-to-integrate-a-haptic-device/24332)

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**Author:** [@leo](https://discourse.slicer.org/u/leo)\
**Replies:** 19\
**Last updated:** [August 1, 2022, 3:23pm UTC](https://discourse.slicer.org/t/loadable-module-to-integrate-a-haptic-device/24332 "2022-08-01T15:23:53Z")

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Hey everyone, I am trying to create a loadable module in order to integrate a haptic device within Slicer. Now I currently managed to have prototypical usage of the devices framework within the module, my next issue is…

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## [Need help making a 3D mesh given co-ordinates of the vertices and vertex indices of each face for 3D Slicer - trimesh/vtkwrite/etc](https://discourse.slicer.org/t/need-help-making-a-3d-mesh-given-co-ordinates-of-the-vertices-and-vertex-indices-of-each-face-for-3d-slicer-trimesh-vtkwrite-etc/24536)

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**Author:** [@jsalas424](https://discourse.slicer.org/u/jsalas424)\
**Replies:** 2\
**Last updated:** [July 28, 2022, 3:19pm UTC](https://discourse.slicer.org/t/need-help-making-a-3d-mesh-given-co-ordinates-of-the-vertices-and-vertex-indices-of-each-face-for-3d-slicer-trimesh-vtkwrite-etc/24536 "2022-07-28T15:19:45Z")

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Hi all, Given the following data: The Cartesian co-ordinates of the vertices in the surface mesh: n vertices x 3 The vertex indices of each face in the surface mesh: n faces x 3 I’m trying to make some 3D file that I…

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## [How to judge a curve model obtained with vtkplanecut or vtkcutter is closed?](https://discourse.slicer.org/t/how-to-judge-a-curve-model-obtained-with-vtkplanecut-or-vtkcutter-is-closed/24470)

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**Author:** [@jumbojing](https://discourse.slicer.org/u/jumbojing)\
**Replies:** 5\
**Last updated:** [July 25, 2022, 10:01pm UTC](https://discourse.slicer.org/t/how-to-judge-a-curve-model-obtained-with-vtkplanecut-or-vtkcutter-is-closed/24470 "2022-07-25T22:01:30Z")

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How to judge a curve model obtained with vtkplanecut or vtkcutter is closed? @lassoan@Juicy@jamesobutler @jcfr @pieper@ jmhuie @manjula @szhang

[Next page](https://discourse.slicer.org/tag/vtk/27.md?match_all_tags=true&page=1&tags%5B%5D=vtk)