# Support

**URL:** https://discourse.vtk.org/c/support/6.md?page=76

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

**Page:** 77

---

## [(Python) Is there a way to Parallel Render with VTK?](https://discourse.vtk.org/t/python-is-there-a-way-to-parallel-render-with-vtk/8460)

<div class="topic-metadata">

**Author:** [@joaomlap](https://discourse.vtk.org/u/joaomlap)\
**Replies:** 1\
**Last updated:** [May 12, 2022, 3:29am UTC](https://discourse.vtk.org/t/python-is-there-a-way-to-parallel-render-with-vtk/8460 "2022-05-12T03:29:25Z")

</div>

I am trying to follow the example showed here: https://gitlab.kitware.com/vtk/vtk/-/blob/v9.1.0/Examples/ParallelProcessing/Generic/Cxx/TaskParallelism.cxx to allow me to parallel render a vtkMultiBlockDataset, the data…

---

## [Bug with vtk Boolean Operation PolyData Filter and implicit functions?](https://discourse.vtk.org/t/bug-with-vtk-boolean-operation-polydata-filter-and-implicit-functions/8479)

<div class="topic-metadata">

**Author:** [@BlueKnight7](https://discourse.vtk.org/u/BlueKnight7)\
**Replies:** 0\
**Last updated:** [May 12, 2022, 12:57am UTC](https://discourse.vtk.org/t/bug-with-vtk-boolean-operation-polydata-filter-and-implicit-functions/8479 "2022-05-12T00:57:28Z")

</div>

This could be a bug or it could be something that I don’t have right with the implementation. The following code correctly renders the UNION of two spheres using the vtkBooleanOperationPolyDataFilter class. BooleanOpe…

---

## [Initial Render() for multiple vtkRenderWindow is slow](https://discourse.vtk.org/t/initial-render-for-multiple-vtkrenderwindow-is-slow/8465)

<div class="topic-metadata">

**Author:** [@mohamadamoud](https://discourse.vtk.org/u/mohamadamoud)\
**Replies:** 2\
**Last updated:** [May 10, 2022, 6:57pm UTC](https://discourse.vtk.org/t/initial-render-for-multiple-vtkrenderwindow-is-slow/8465 "2022-05-10T18:57:20Z")

</div>

I want to render about 40 vtkRenderWindow objects each with its own image. The issue is my initial render is slow, it takes about 100-200 ms per render window. My pipeline can be seen in the code below. I am using vtk8…

---

## [MacOS Font Render is Jaggy (VTK 9.1)](https://discourse.vtk.org/t/macos-font-render-is-jaggy-vtk-9-1/8415)

<div class="topic-metadata">

**Author:** [@Michael\_Jackson](https://discourse.vtk.org/u/Michael_Jackson)\
**Replies:** 8\
**Last updated:** [May 9, 2022, 3:30pm UTC](https://discourse.vtk.org/t/macos-font-render-is-jaggy-vtk-9-1/8415 "2022-05-09T15:30:46Z")

</div>

I know this has been asked in the past but I just cant seem to find the posts. How does one get the font for things like the CubeAxisActor to look “nice” on macOS? They are all jaggy on my macOS machine but nice looking …

---

## [vtkImplicitBoolean Nested Operations Example Needed](https://discourse.vtk.org/t/vtkimplicitboolean-nested-operations-example-needed/8445)

<div class="topic-metadata">

**Author:** [@BlueKnight7](https://discourse.vtk.org/u/BlueKnight7)\
**Replies:** 0\
**Last updated:** [May 8, 2022, 9:24pm UTC](https://discourse.vtk.org/t/vtkimplicitboolean-nested-operations-example-needed/8445 "2022-05-08T21:24:43Z")

</div>

The https://vtk.org/doc/nightly/html/classvtkImplicitBoolean.html webpage mentions " You can use nested combinations of vtkImplicitFunction’s (and/or vtkImplicitBoolean) to create elaborate implicit functions". Is there…

---

## [How to get shader source for an actor](https://discourse.vtk.org/t/how-to-get-shader-source-for-an-actor/8408)

<div class="topic-metadata">

**Author:** [@BlueKnight7](https://discourse.vtk.org/u/BlueKnight7)\
**Replies:** 13\
**Last updated:** [May 6, 2022, 2:20pm UTC](https://discourse.vtk.org/t/how-to-get-shader-source-for-an-actor/8408 "2022-05-06T14:20:03Z")

</div>

I know from the nightly build documentation for 9.1 that I can use the GetSource function of vtkShader to retrieve the source (as a string) for the shader. Or, at least I hope that I can. I also know from the examples t…

---

## [vtkImageData to png](https://discourse.vtk.org/t/vtkimagedata-to-png/8418)

<div class="topic-metadata">

**Author:** [@s195t](https://discourse.vtk.org/u/s195t)\
**Replies:** 3\
**Last updated:** [May 4, 2022, 1:21pm UTC](https://discourse.vtk.org/t/vtkimagedata-to-png/8418 "2022-05-04T13:21:15Z")

</div>

Dear everyone, I would like to export a vtkImageData of 500x500 cells to a png picture of exactly 500x500 pixel resolution. In this way, every pixel should be approximately corresponding to a cell. This means fitting m…

---

## [VTK-examples FrogSlice](https://discourse.vtk.org/t/vtk-examples-frogslice/8364)

<div class="topic-metadata">

**Author:** [@Chris9810](https://discourse.vtk.org/u/Chris9810)\
**Replies:** 2\
**Last updated:** [May 4, 2022, 11:03am UTC](https://discourse.vtk.org/t/vtk-examples-frogslice/8364 "2022-05-04T11:03:50Z")

</div>

Hi, I’m a beginner about VTK. I want to learn the FrogSlice-example in VTK website. The example provides C++ code and CMakeList.txt, but no raw image data. I would greatly appreciate it if anyone could tell me about ho…

---

## [vtkActor::SetUserMatrix make the vtkPolyData incorrect](https://discourse.vtk.org/t/vtkactor-setusermatrix-make-the-vtkpolydata-incorrect/8417)

<div class="topic-metadata">

**Author:** [@zhang-qiang-github](https://discourse.vtk.org/u/zhang-qiang-github)\
**Replies:** 1\
**Last updated:** [May 3, 2022, 7:14pm UTC](https://discourse.vtk.org/t/vtkactor-setusermatrix-make-the-vtkpolydata-incorrect/8417 "2022-05-03T19:14:09Z")

</div>

I am using vtkContourFilter in my application, and the result is correct: Then, I use vtkActor::SetUserMatrix to correct the direction, and my code is: double ele\[16\] = { 1, 0, 0, 0, 0, -1, 0, 0, 0, 0, 1, 0, …

---

## [Can I update part of Volmue for grinding and Drilling?](https://discourse.vtk.org/t/can-i-update-part-of-volmue-for-grinding-and-drilling/8410)

<div class="topic-metadata">

**Author:** [@tdchen](https://discourse.vtk.org/u/tdchen)\
**Replies:** 4\
**Last updated:** [May 3, 2022, 3:25am UTC](https://discourse.vtk.org/t/can-i-update-part-of-volmue-for-grinding-and-drilling/8410 "2022-05-03T03:25:38Z")

</div>

I can’t find a way to update part of vtkImageData in the pipeline, I think it would be difficult. It involves update gradients behind the scene. Is that true? I hope to get some suggestions. Thank you.

---

## [How to Set the DateDir for vtk examples](https://discourse.vtk.org/t/how-to-set-the-datedir-for-vtk-examples/8413)

<div class="topic-metadata">

**Author:** [@wolf\_wild](https://discourse.vtk.org/u/wolf_wild)\
**Replies:** 0\
**Last updated:** [May 2, 2022, 9:52am UTC](https://discourse.vtk.org/t/how-to-set-the-datedir-for-vtk-examples/8413 "2022-05-02T09:52:22Z")

</div>

I am new for VTK . I do not know how to set the command line about the date dir for the examples and tests. I have download all data and save it in Dir ExternalData.Who can help me

---

## [How to call Examples Data Easily for VTK Examples?](https://discourse.vtk.org/t/how-to-call-examples-data-easily-for-vtk-examples/8371)

<div class="topic-metadata">

**Author:** [@Freya\_the\_Goddess](https://discourse.vtk.org/u/Freya_the_Goddess)\
**Replies:** 3\
**Last updated:** [May 1, 2022, 9:55pm UTC](https://discourse.vtk.org/t/how-to-call-examples-data-easily-for-vtk-examples/8371 "2022-05-01T21:55:33Z")

</div>

Hi all, good day to you all… I have git clone this repository: then build it using Cmake After that I test Delaunay3D, it needs .vtp file, so I choose Bunny.vtp the file is in the ‘vtk-examples/src/Testing/Data’ …

---

## [Compute the volume of the intersection between two vtkPolyData objects](https://discourse.vtk.org/t/compute-the-volume-of-the-intersection-between-two-vtkpolydata-objects/8338)

<div class="topic-metadata">

**Author:** [@Robert\_Sawko](https://discourse.vtk.org/u/Robert_Sawko)\
**Replies:** 7\
**Last updated:** [May 1, 2022, 4:19pm UTC](https://discourse.vtk.org/t/compute-the-volume-of-the-intersection-between-two-vtkpolydata-objects/8338 "2022-05-01T16:19:36Z")

</div>

Hello, I would to compute a volume of the intersection between two vtkPolyData objects (or their bounding boxes). I have been mainly working with ParaView Python interface and created a programmable filter to display th…

---

## [How to get coordinates of dicom image and check intensity values over it?](https://discourse.vtk.org/t/how-to-get-coordinates-of-dicom-image-and-check-intensity-values-over-it/2281)

<div class="topic-metadata">

**Author:** [@Pooja](https://discourse.vtk.org/u/Pooja)\
**Replies:** 8\
**Last updated:** [April 29, 2022, 8:44am UTC](https://discourse.vtk.org/t/how-to-get-coordinates-of-dicom-image-and-check-intensity-values-over-it/2281 "2022-04-29T08:44:04Z")

</div>

Hello, I am using ITK and VTK for liver segmentation purpose. But my ITK segmentation algorithm needs seed point which I have to select from DICOM images. Firstly, I was using 3D slicer to take seed point positions. But…

---

## [Equivalent rotations of a set of rotations.](https://discourse.vtk.org/t/equivalent-rotations-of-a-set-of-rotations/8355)

<div class="topic-metadata">

**Author:** [@Luis\_Carlos\_Carneiro](https://discourse.vtk.org/u/Luis_Carlos_Carneiro)\
**Replies:** 2\
**Last updated:** [April 28, 2022, 12:38pm UTC](https://discourse.vtk.org/t/equivalent-rotations-of-a-set-of-rotations/8355 "2022-04-28T12:38:42Z")

</div>

Dear All, Are there some site that I can convert the following set of rotations, of a 3D picture, i.e. Rot Axe Y → Rot Axe X → Rot Axe Z → Rot Axe X → Rot Axe Y (or any other set of rotations) in Rot Axe X → Rot Axe …

---

## [Surface LIC python](https://discourse.vtk.org/t/surface-lic-python/8386)

<div class="topic-metadata">

**Author:** [@s195t](https://discourse.vtk.org/u/s195t)\
**Replies:** 0\
**Last updated:** [April 27, 2022, 9:09am UTC](https://discourse.vtk.org/t/surface-lic-python/8386 "2022-04-27T09:09:42Z")

</div>

Dear everyone, I would need to systematically produce LICs from randomly generated velocity fields in python, which I am doing now modifying a third party library I have seen that Paraview has a plugin to do so, wanted…

---

## [stl to solid mesh file](https://discourse.vtk.org/t/stl-to-solid-mesh-file/8379)

<div class="topic-metadata">

**Author:** [@hye00525](https://discourse.vtk.org/u/hye00525)\
**Replies:** 6\
**Last updated:** [April 27, 2022, 7:11am UTC](https://discourse.vtk.org/t/stl-to-solid-mesh-file/8379 "2022-04-27T07:11:26Z")

</div>

Hello, I have two questions. I have a .stl mesh file that is hollow inside. Can I change this to a solid mesh file in vtk? (e.g., Convert stl file to solid (from Magics to Solidworks or Catia)?) Or can I save vtkpoly…

---

## [vtkpolydata is black when it is included in vtkVolume](https://discourse.vtk.org/t/vtkpolydata-is-black-when-it-is-included-in-vtkvolume/8382)

<div class="topic-metadata">

**Author:** [@zhang-qiang-github](https://discourse.vtk.org/u/zhang-qiang-github)\
**Replies:** 0\
**Last updated:** [April 26, 2022, 2:17pm UTC](https://discourse.vtk.org/t/vtkpolydata-is-black-when-it-is-included-in-vtkvolume/8382 "2022-04-26T14:17:22Z")

</div>

Currently, I want to display vtkVolume and vtkPolyData in a render. But, the part of vtkPolyData, which is covered by vtkVolume, is black. Like the following figure: The line outside of vtkVolume is red, which is wha…

---

## [How to set face color for vtkAnnotatedCubeActor?](https://discourse.vtk.org/t/how-to-set-face-color-for-vtkannotatedcubeactor/8378)

<div class="topic-metadata">

**Author:** [@zhang-qiang-github](https://discourse.vtk.org/u/zhang-qiang-github)\
**Replies:** 0\
**Last updated:** [April 26, 2022, 3:33am UTC](https://discourse.vtk.org/t/how-to-set-face-color-for-vtkannotatedcubeactor/8378 "2022-04-26T03:33:32Z")

</div>

I am using vtkAnnotatedCubeActor in my application. It has method GetXPlusFaceProperty to change the text color, but I can not find a method to change the color of face. Fortunately, a solution has been provided by: h…

---

## [Bash: vtk command not found](https://discourse.vtk.org/t/bash-vtk-command-not-found/8220)

<div class="topic-metadata">

**Author:** [@Freya\_the\_Goddess](https://discourse.vtk.org/u/Freya_the_Goddess)\
**Replies:** 23\
**Last updated:** [April 25, 2022, 1:00pm UTC](https://discourse.vtk.org/t/bash-vtk-command-not-found/8220 "2022-04-25T13:00:32Z")

</div>

Dear all, I have installed VTK from source using CMake, and I couldn’t run vtk mace.tcl I see the tutorial here: (The Visualization Toolkit) it said “vtk command not found” I have adjusted the environment variables…

---

## [vtkTextActor + orientation = please help](https://discourse.vtk.org/t/vtktextactor-orientation-please-help/8370)

<div class="topic-metadata">

**Author:** [@Olivier](https://discourse.vtk.org/u/Olivier)\
**Replies:** 0\
**Last updated:** [April 25, 2022, 12:11pm UTC](https://discourse.vtk.org/t/vtktextactor-orientation-please-help/8370 "2022-04-25T12:11:04Z")

</div>

Hi friend, I’m using vtkTextActor to display very basic text inside a scene. I want to orient the text, so I’m using vtkTextActor.SetOrientation Here a sample of what I get by creating an actor for each angle from 0 t…

---

## [python 3.10 and pip(version 21.3.1) import vtk](https://discourse.vtk.org/t/python-3-10-and-pip-version-21-3-1-import-vtk/7338)

<div class="topic-metadata">

**Author:** [@Tiago\_Mimoso](https://discourse.vtk.org/u/Tiago_Mimoso)\
**Replies:** 5\
**Last updated:** [April 25, 2022, 8:37am UTC](https://discourse.vtk.org/t/python-3-10-and-pip-version-21-3-1-import-vtk/7338 "2022-04-25T08:37:38Z")

</div>

Hi, I’m trying to install the vtk packages though pip typing “pip install vtk” but the error message is “ERROR: Could not find a version that satisfies the requirement vtk (from versions: none) ERROR: No matching distr…

---

## [OpenGL State Errors with QVTKOpenGLWidget](https://discourse.vtk.org/t/opengl-state-errors-with-qvtkopenglwidget/8365)

<div class="topic-metadata">

**Author:** [@Panda12197](https://discourse.vtk.org/u/Panda12197)\
**Replies:** 0\
**Last updated:** [April 25, 2022, 2:25am UTC](https://discourse.vtk.org/t/opengl-state-errors-with-qvtkopenglwidget/8365 "2022-04-25T02:25:23Z")

</div>

Hello Guys, I have a problem in visualizing point cloud with QVTKOpenGLWidget. I promoted the QWidget to QVTKOpenGLWidget and load point cloud data to the Widget. As soon as the MainWindow is appeared, the following er…

---

## [Single-sided lighting model](https://discourse.vtk.org/t/single-sided-lighting-model/8361)

<div class="topic-metadata">

**Author:** [@BlueKnight7](https://discourse.vtk.org/u/BlueKnight7)\
**Replies:** 0\
**Last updated:** [April 25, 2022, 12:23am UTC](https://discourse.vtk.org/t/single-sided-lighting-model/8361 "2022-04-25T00:23:56Z")

</div>

It appears that the default is to render with two-sided lighting. How can I get single-sided lighting?

---

## [Tests not found](https://discourse.vtk.org/t/tests-not-found/8351)

<div class="topic-metadata">

**Author:** [@ghlecl](https://discourse.vtk.org/u/ghlecl)\
**Replies:** 6\
**Last updated:** [April 23, 2022, 3:23pm UTC](https://discourse.vtk.org/t/tests-not-found/8351 "2022-04-23T15:23:20Z")

</div>

Hello. I am trying to build VTK, and then run the tests on my machine. I am using CMake 3.22.4. I have downloaded the release source tarball for VTK on the website (version 9.1.0). I am on macOS (Big Sur 11.6.5). I ha…

---

## [Write an ellipsoid source and a set of points to a file](https://discourse.vtk.org/t/write-an-ellipsoid-source-and-a-set-of-points-to-a-file/8347)

<div class="topic-metadata">

**Author:** [@anirudh\_puligandla](https://discourse.vtk.org/u/anirudh_puligandla)\
**Replies:** 1\
**Last updated:** [April 22, 2022, 10:03am UTC](https://discourse.vtk.org/t/write-an-ellipsoid-source-and-a-set-of-points-to-a-file/8347 "2022-04-22T10:03:57Z")

</div>

Hello, I am trying to put together an ellipsoid source and a set of points into one scene, write it to a .ply file and display it using paraview. I am having trouble combining two polyData, one from ellipsoid and anothe…

---

## [DataSetmapper + LookupTable : hide range](https://discourse.vtk.org/t/datasetmapper-lookuptable-hide-range/8345)

<div class="topic-metadata">

**Author:** [@Olivier](https://discourse.vtk.org/u/Olivier)\
**Replies:** 1\
**Last updated:** [April 21, 2022, 10:25am UTC](https://discourse.vtk.org/t/datasetmapper-lookuptable-hide-range/8345 "2022-04-21T10:25:48Z")

</div>

Hi friends, I have a vtkUnstructuredGrid containing triangles and points data as scalars. I’m displaying it with a vtkDataSetMapper linked to a vtkLookupTable. Here is the resulting display : Now what I want to do…

---

## [How to draw scout/reference lines in dicom for multi series ?](https://discourse.vtk.org/t/how-to-draw-scout-reference-lines-in-dicom-for-multi-series/8344)

<div class="topic-metadata">

**Author:** [@Usha\_Diggi](https://discourse.vtk.org/u/Usha_Diggi)\
**Replies:** 0\
**Last updated:** [April 21, 2022, 8:19am UTC](https://discourse.vtk.org/t/how-to-draw-scout-reference-lines-in-dicom-for-multi-series/8344 "2022-04-21T08:19:27Z")

</div>

Hi everyone, I am new to VTK, currently exploring about scout line /localizer line implementation for DICOM series but no luck there is no reference link/examples. I would appreciate your help on this. Thank you Reg…

---

## [DLL load failure when importing vtkFiltersExtraction](https://discourse.vtk.org/t/dll-load-failure-when-importing-vtkfiltersextraction/8343)

<div class="topic-metadata">

**Author:** [@JayEspi](https://discourse.vtk.org/u/JayEspi)\
**Replies:** 1\
**Last updated:** [April 20, 2022, 8:31pm UTC](https://discourse.vtk.org/t/dll-load-failure-when-importing-vtkfiltersextraction/8343 "2022-04-20T20:31:08Z")

</div>

Setup: Windows 10, Anaconda, Python v3.9 When I try to import vtkFiltersExtraction: import vtkmodules.vtkFiltersExtraction I get this error: ImportError: DLL load failed while importing vtkFiltersExtraction: The spec…

---

## [vtkDataSetSurfaceFilter](https://discourse.vtk.org/t/vtkdatasetsurfacefilter/8336)

<div class="topic-metadata">

**Author:** [@andreasbuykx](https://discourse.vtk.org/u/andreasbuykx)\
**Replies:** 3\
**Last updated:** [April 20, 2022, 3:24pm UTC](https://discourse.vtk.org/t/vtkdatasetsurfacefilter/8336 "2022-04-20T15:24:27Z")

</div>

@will.schroeder The vtkDataSetSurfaceFilter may delegate its processing to an internal vtkGeometryFilter which has been parallelized and now may be much faster. The delegation is switched off by default though, because …

[Previous page](https://discourse.vtk.org/c/support/6.md?page=75)

[Next page](https://discourse.vtk.org/c/support/6.md?page=77)