# Support

**URL:** https://discourse.vtk.org/c/support/6.md?page=56

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

**Page:** 57

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## [SetOrigin do not work for actor with trackball interactor style](https://discourse.vtk.org/t/setorigin-do-not-work-for-actor-with-trackball-interactor-style/10476)

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**Author:** [@zhang-qiang-github](https://discourse.vtk.org/u/zhang-qiang-github)\
**Replies:** 7\
**Last updated:** [February 3, 2023, 9:21pm UTC](https://discourse.vtk.org/t/setorigin-do-not-work-for-actor-with-trackball-interactor-style/10476 "2023-02-03T21:21:51Z")

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I am using vtkInteractorStyleTrackballActor with Spin method. For Spin method, the actor would rotate along the actor center. How can I change the rotation center? Does actor.SetOrigin work? The explanation of SetOrigi…

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## [changing the PointSource model](https://discourse.vtk.org/t/changing-the-pointsource-model/10586)

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**Author:** [@sandy](https://discourse.vtk.org/u/sandy)\
**Replies:** 10\
**Last updated:** [February 3, 2023, 8:44pm UTC](https://discourse.vtk.org/t/changing-the-pointsource-model/10586 "2023-02-03T20:44:26Z")

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Hi, this is my first day with vtk-js-master. The random spherical point cloud demo works fine for me with 10000 points, it looks like a snowball. As a first step I have modified the index.js in the vtk-js-master/Sources/…

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## [How to use vtkResliceCursorWidget ??](https://discourse.vtk.org/t/how-to-use-vtkreslicecursorwidget/10604)

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**Author:** [@kookoo9999](https://discourse.vtk.org/u/kookoo9999)\
**Replies:** 1\
**Last updated:** [February 3, 2023, 3:38pm UTC](https://discourse.vtk.org/t/how-to-use-vtkreslicecursorwidget/10604 "2023-02-03T15:38:13Z")

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Hello I’m tryna use vtkReslicecursor to update the Reslice Image when I control the widget on 3D View or MPR like this and I’m looking for example of using vtkResliceCursor but I could’nt find… Is there some example u…

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## [Change color of vtkCubeAxesActor](https://discourse.vtk.org/t/change-color-of-vtkcubeaxesactor/10584)

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**Author:** [@BlueKnight7](https://discourse.vtk.org/u/BlueKnight7)\
**Replies:** 2\
**Last updated:** [February 2, 2023, 7:56pm UTC](https://discourse.vtk.org/t/change-color-of-vtkcubeaxesactor/10584 "2023-02-02T19:56:20Z")

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Referring to example: https://kitware.github.io/vtk-examples/site/Cxx/Utilities/DetermineActorType/ Notice that with this example the axes and axes labels are in white. After looking at the on-line documentation and …

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## [question about mesh color mapping](https://discourse.vtk.org/t/question-about-mesh-color-mapping/10578)

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**Author:** [@xianger.qi](https://discourse.vtk.org/u/xianger.qi)\
**Replies:** 1\
**Last updated:** [February 2, 2023, 6:52pm UTC](https://discourse.vtk.org/t/question-about-mesh-color-mapping/10578 "2023-02-02T18:52:42Z")

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I divide the volume data into two parts, firstly, one is color with green and the other is color with white then to extract isosurface. when the tools is moving and touch with the white part, the white region will be col…

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## [Stream trace on a shell?](https://discourse.vtk.org/t/stream-trace-on-a-shell/10587)

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**Author:** [@rexthor](https://discourse.vtk.org/u/rexthor)\
**Replies:** 0\
**Last updated:** [February 1, 2023, 8:33pm UTC](https://discourse.vtk.org/t/stream-trace-on-a-shell/10587 "2023-02-01T20:33:27Z")

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Hi - I have a surface defined as an unstructured grid composed of vtkTriangles. It is roughly a dish shape, and has a vector array (flow velocity) at each cell center. Is there a way to trace a streamline on this surface…

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## [Changing dimensions and number of scalar components for vtkImageData](https://discourse.vtk.org/t/changing-dimensions-and-number-of-scalar-components-for-vtkimagedata/10550)

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**Author:** [@kit](https://discourse.vtk.org/u/kit)\
**Replies:** 6\
**Last updated:** [January 31, 2023, 1:43pm UTC](https://discourse.vtk.org/t/changing-dimensions-and-number-of-scalar-components-for-vtkimagedata/10550 "2023-01-31T13:43:08Z")

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Hi All, I have vtkImageData object with dimensions (nx,ny,nz) with 1 scalar component, but for various reasons, I’d like to be able to work on it as a vtkImageData with dimensions (ny,nz,1) and nx scalar components with…

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## [vtkContourGrid example](https://discourse.vtk.org/t/vtkcontourgrid-example/10455)

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**Author:** [@BlueKnight7](https://discourse.vtk.org/u/BlueKnight7)\
**Replies:** 8\
**Last updated:** [January 31, 2023, 3:17am UTC](https://discourse.vtk.org/t/vtkcontourgrid-example/10455 "2023-01-31T03:17:11Z")

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I am looking for a vtkContourGrid example since I couldn’t find one with the online vtkContourGrid class documentation. I have scalar cell data assigned to my vtkUnstructuredGrid object. Based on the vtkContourFilter e…

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## [Does VTK has a class which can write NRRD file?](https://discourse.vtk.org/t/does-vtk-has-a-class-which-can-write-nrrd-file/10556)

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**Author:** [@Sterben\_01](https://discourse.vtk.org/u/Sterben_01)\
**Replies:** 4\
**Last updated:** [January 31, 2023, 1:45am UTC](https://discourse.vtk.org/t/does-vtk-has-a-class-which-can-write-nrrd-file/10556 "2023-01-31T01:45:26Z")

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Hi! I’m trying to find a class which is like vtkNrrdWriter. But I didn’t find it. Is there some way I can get the same result? I want to write the file to NRRD format.

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## [SetFontSize on vtkCubeAxesActor bug?](https://discourse.vtk.org/t/setfontsize-on-vtkcubeaxesactor-bug/520)

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**Author:** [@tomtomatron](https://discourse.vtk.org/u/tomtomatron)\
**Replies:** 3\
**Last updated:** [January 31, 2023, 12:16am UTC](https://discourse.vtk.org/t/setfontsize-on-vtkcubeaxesactor-bug/520 "2023-01-31T00:16:40Z")

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How can I set the font size of the TitleTextProperty of a vtkCubeAxesActor? The code below does not result in the specified font size of the vtkCubeAxesActor when plotting. import vtk ca = vtk.vtkCubeAxesActor() ca.G…

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## [Universal Scene Description (USD) scene importer/exporter?](https://discourse.vtk.org/t/universal-scene-description-usd-scene-importer-exporter/6452)

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**Author:** [@lassoan](https://discourse.vtk.org/u/lassoan)\
**Replies:** 4\
**Last updated:** [January 30, 2023, 11:00pm UTC](https://discourse.vtk.org/t/universal-scene-description-usd-scene-importer-exporter/6452 "2023-01-30T23:00:11Z")

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Are there any plans for adding importer/exporter for Universal Scene Description (USD) format? It looks like a very nice and widely supported file format for data exchange, which is much friendlier than low-level glTF fi…

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## [VTK9 create different stencil than vtk8](https://discourse.vtk.org/t/vtk9-create-different-stencil-than-vtk8/10560)

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**Author:** [@lucas\_rouhier](https://discourse.vtk.org/u/lucas_rouhier)\
**Replies:** 6\
**Last updated:** [January 30, 2023, 5:01pm UTC](https://discourse.vtk.org/t/vtk9-create-different-stencil-than-vtk8/10560 "2023-01-30T17:01:45Z")

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Hello, I am having some weird results while trying to update my VTK. I am converting a VTK polydata to Image data with the following code: vtkSmartPointer VtkPolyDataToImage(vtkPolyData\* poly, vtkImageData\* templateIm…

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## [vtkLabeledDataMapper =\> all texts disappearing issue](https://discourse.vtk.org/t/vtklabeleddatamapper-all-texts-disappearing-issue/10402)

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**Author:** [@Olivier](https://discourse.vtk.org/u/Olivier)\
**Replies:** 7\
**Last updated:** [January 30, 2023, 8:46am UTC](https://discourse.vtk.org/t/vtklabeleddatamapper-all-texts-disappearing-issue/10402 "2023-01-30T08:46:19Z")

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Hi friends, I’m using a vtkLabeledDataMapper to display multiple strings at 3D positions. Mapper is filled in with a vtkPolyData containing points (for positions) and data arrays (one for strings and one for types = te…

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## [Creating a new CMakeLists.txt for building and using vtkOSPRay\* with c++](https://discourse.vtk.org/t/creating-a-new-cmakelists-txt-for-building-and-using-vtkospray-with-c/10526)

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**Author:** [@Spacetracker](https://discourse.vtk.org/u/Spacetracker)\
**Replies:** 13\
**Last updated:** [January 27, 2023, 4:18pm UTC](https://discourse.vtk.org/t/creating-a-new-cmakelists-txt-for-building-and-using-vtkospray-with-c/10526 "2023-01-27T16:18:06Z")

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I successfully built OSPRay and VTK 9/8 with it and the Rendering vtkExamples and Tests/Testing are working. I am having difficulty updating my own CMakeLists.txt file for c++ to “make” the includes and libraries known …

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## [vtkAssembly transform propagation](https://discourse.vtk.org/t/vtkassembly-transform-propagation/10547)

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**Author:** [@TartaPise](https://discourse.vtk.org/u/TartaPise)\
**Replies:** 0\
**Last updated:** [January 26, 2023, 1:27pm UTC](https://discourse.vtk.org/t/vtkassembly-transform-propagation/10547 "2023-01-26T13:27:49Z")

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Hello everyone, I noticed that using vtkAssembly-\>SetUserTransform() does not update the corresponding vtkActors transform thus their center and orientation. Do you think this makes sense? Wouldn’t it be better to propag…

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## [Why would I need to sweep polygonal data when working with contours?](https://discourse.vtk.org/t/why-would-i-need-to-sweep-polygonal-data-when-working-with-contours/10541)

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**Author:** [@SebastianWilke](https://discourse.vtk.org/u/SebastianWilke)\
**Replies:** 1\
**Last updated:** [January 26, 2023, 6:57am UTC](https://discourse.vtk.org/t/why-would-i-need-to-sweep-polygonal-data-when-working-with-contours/10541 "2023-01-26T06:57:57Z")

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Hi! A comment in this PolyDataContourToImageData example claims: // sweep polygonal data (this is the important thing with contours!) I am working with contours read from a DICOM file and would like to avoid errors …

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## [Configure VTK project stuck at \[100%\] Linking cxx executable](https://discourse.vtk.org/t/configure-vtk-project-stuck-at-100-linking-cxx-executable/10542)

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**Author:** [@Sterben\_01](https://discourse.vtk.org/u/Sterben_01)\
**Replies:** 2\
**Last updated:** [January 26, 2023, 6:40am UTC](https://discourse.vtk.org/t/configure-vtk-project-stuck-at-100-linking-cxx-executable/10542 "2023-01-26T06:40:50Z")

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Hi! I’m just compiled and installed the VTK 9.2. I have a simple project and this is my CMakeList.txt cmake\_minimum\_required(VERSION 3.16) project (Helloworld) find\_package (VTK REQUIRED) include\_directories(${VTK\_INC…

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## [Using a C# VTK for Windows application through a browser](https://discourse.vtk.org/t/using-a-c-vtk-for-windows-application-through-a-browser/10510)

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**Author:** [@JimCR1966](https://discourse.vtk.org/u/JimCR1966)\
**Replies:** 4\
**Last updated:** [January 25, 2023, 9:27pm UTC](https://discourse.vtk.org/t/using-a-c-vtk-for-windows-application-through-a-browser/10510 "2023-01-25T21:27:11Z")

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I am trying to build a version of my C# (VS 2022) that can run through a browser using Cybelesoft’s Thinfinity Virtual UI. The vtkrendered windows do not work (simply not rendered). Has anybody else tried this? Is there …

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## [Python pip install 9.0.1 not installing](https://discourse.vtk.org/t/python-pip-install-9-0-1-not-installing/3864)

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**Author:** [@Gresliebear](https://discourse.vtk.org/u/Gresliebear)\
**Replies:** 4\
**Last updated:** [January 24, 2023, 2:45pm UTC](https://discourse.vtk.org/t/python-pip-install-9-0-1-not-installing/3864 "2023-01-24T14:45:16Z")

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I am calling vtk from requirements.txt but it could not find the latest version Could not find a version that satisfies the requirement vtk==9.0.1 (from -r requirements.txt (line 87)) (from versions: 8.0.0.dev2017071…

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## [why are my negative contours not generating with vtk.vtkContourFilter?](https://discourse.vtk.org/t/why-are-my-negative-contours-not-generating-with-vtk-vtkcontourfilter/10525)

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**Author:** [@Derek\_Eden](https://discourse.vtk.org/u/Derek_Eden)\
**Replies:** 0\
**Last updated:** [January 23, 2023, 4:12pm UTC](https://discourse.vtk.org/t/why-are-my-negative-contours-not-generating-with-vtk-vtkcontourfilter/10525 "2023-01-23T16:12:31Z")

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I am using vtk.vtkContourFilter to create isolines from a dataset. Everything seems to work fine, but any contour values I specify \<= 0 don’t seem to generate, even though there is definitely data with those values. I …

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## [How to get separate boundary for a tube?](https://discourse.vtk.org/t/how-to-get-separate-boundary-for-a-tube/10521)

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**Author:** [@zhang-qiang-github](https://discourse.vtk.org/u/zhang-qiang-github)\
**Replies:** 3\
**Last updated:** [January 23, 2023, 11:00am UTC](https://discourse.vtk.org/t/how-to-get-separate-boundary-for-a-tube/10521 "2023-01-23T11:00:44Z")

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For a tube without cap, I want to obtain the two cap. The boundary is calculated as: fe = vtk.vtkFeatureEdges() fe.SetInputData(tubePoly) fe.BoundaryEdgesOn() fe.FeatureEdgesOff() fe.NonManifoldEdgesOff() fe.ManifoldEd…

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## [NativeVTK Android Black Screen](https://discourse.vtk.org/t/nativevtk-android-black-screen/10106)

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**Author:** [@perphy](https://discourse.vtk.org/u/perphy)\
**Replies:** 2\
**Last updated:** [January 23, 2023, 9:14am UTC](https://discourse.vtk.org/t/nativevtk-android-black-screen/10106 "2023-01-23T09:14:39Z")

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Hi, I want to run vtk on android. I build vtk9.2.2 with ndk 25 on ubuntu. I try to run the official example NativeVTK. But I get black screen. Similar with Is vtk9.2.2 to new and not compatible with the newest and…

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## [Extracting particle physics from streamlines](https://discourse.vtk.org/t/extracting-particle-physics-from-streamlines/10518)

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**Author:** [@alanpatterson](https://discourse.vtk.org/u/alanpatterson)\
**Replies:** 1\
**Last updated:** [January 23, 2023, 7:31am UTC](https://discourse.vtk.org/t/extracting-particle-physics-from-streamlines/10518 "2023-01-23T07:31:50Z")

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I am trying to work out the correct method for recovering a particle’s movement in a vector field, from using the streamline integration of the vector field. Let’s say I have a vector velocity field. I generate streamli…

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## [vtkGradientFilter segmentation fault](https://discourse.vtk.org/t/vtkgradientfilter-segmentation-fault/10516)

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**Author:** [@FanWang10](https://discourse.vtk.org/u/FanWang10)\
**Replies:** 1\
**Last updated:** [January 22, 2023, 9:44pm UTC](https://discourse.vtk.org/t/vtkgradientfilter-segmentation-fault/10516 "2023-01-22T21:44:12Z")

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Hello, I am using to calculate the gradient of each vertex in an unstructured grid. I followed this example and made some changes: https://gitlab.kitware.com/vtk/vtk/-/blob/v9.2.0/Accelerators/Vtkm/Filters/Testing/Cxx/…

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## [vtkPolyData parallel processing](https://discourse.vtk.org/t/vtkpolydata-parallel-processing/10457)

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**Author:** [@Jens\_Munk\_Hansen](https://discourse.vtk.org/u/Jens_Munk_Hansen)\
**Replies:** 4\
**Last updated:** [January 22, 2023, 6:59pm UTC](https://discourse.vtk.org/t/vtkpolydata-parallel-processing/10457 "2023-01-22T18:59:18Z")

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I am currently in a situation where I have vtkPolyData containing many points, but only a subset of these points are vertices in a mesh and have normals associated. I would like to like to perform some heavy operations …

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## [Fill / Color area of closed polyline](https://discourse.vtk.org/t/fill-color-area-of-closed-polyline/10497)

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**Author:** [@SebastianWilke](https://discourse.vtk.org/u/SebastianWilke)\
**Replies:** 4\
**Last updated:** [January 22, 2023, 6:47pm UTC](https://discourse.vtk.org/t/fill-color-area-of-closed-polyline/10497 "2023-01-22T18:47:43Z")

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Hello! I am rendering DICOM contours (Yes, against advice to use existing implementations). At the moment, I am creating vtkPolyData using vtkPoints and vtkCellArray from the 3D-point data extracted from DICOM. Then, I …

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## [How to label vtkPolyData?](https://discourse.vtk.org/t/how-to-label-vtkpolydata/10513)

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**Author:** [@zhang-qiang-github](https://discourse.vtk.org/u/zhang-qiang-github)\
**Replies:** 5\
**Last updated:** [January 21, 2023, 10:28am UTC](https://discourse.vtk.org/t/how-to-label-vtkpolydata/10513 "2023-01-21T10:28:48Z")

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For example, I have two poly data: poly1 & poly2. I want to use vtkAppendPolyData to merge the two polydata and get polyFinal. Is it possible to label poly1 and poly2 before vtkAppendPolyData so that I can know the cell…

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## [Extracting isosurface from a vtkImageData](https://discourse.vtk.org/t/extracting-isosurface-from-a-vtkimagedata/10502)

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**Author:** [@Jishnu](https://discourse.vtk.org/u/Jishnu)\
**Replies:** 9\
**Last updated:** [January 21, 2023, 10:27am UTC](https://discourse.vtk.org/t/extracting-isosurface-from-a-vtkimagedata/10502 "2023-01-21T10:27:28Z")

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I am trying to create an isosurface plot from a vtkImageData. I have a numpy array which has the scalar fields. I kept the scalar field as 0 and 1 for testing. Given below is my pipeline: import vtk from vtk.util import…

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## [Adding a link library to a module](https://discourse.vtk.org/t/adding-a-link-library-to-a-module/10480)

<div class="topic-metadata">

**Author:** [@djduke](https://discourse.vtk.org/u/djduke)\
**Replies:** 3\
**Last updated:** [January 21, 2023, 3:02am UTC](https://discourse.vtk.org/t/adding-a-link-library-to-a-module/10480 "2023-01-21T03:02:53Z")

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If I want to link an external library to a module I believe I need to use target\_link\_library(…). However when I try this with the Wrapping example module from the distribution I getan error when configuring cmake: t…

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## [Experiencing ImportErrror when loading vtk constants](https://discourse.vtk.org/t/experiencing-importerrror-when-loading-vtk-constants/10448)

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**Author:** [@Maximilian\_Nentwich](https://discourse.vtk.org/u/Maximilian_Nentwich)\
**Replies:** 1\
**Last updated:** [January 21, 2023, 2:57am UTC](https://discourse.vtk.org/t/experiencing-importerrror-when-loading-vtk-constants/10448 "2023-01-21T02:57:26Z")

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Hi VTK forum, I am getting an error when importing vtk (as part of brainspace) ImportError: cannot import name 'VTK\_UNICODE\_STRING' from 'vtk.util.vtkConstants' from the following command: from brainspace.null\_models…

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