# Support

**URL:** https://discourse.vtk.org/c/support/6.md?page=115

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

**Page:** 116

---

## [SIGSEGV (Segmentation fault) on freeing memory vtkSmartPointer\<vtkImageData\> (NIFTY)](https://discourse.vtk.org/t/sigsegv-segmentation-fault-on-freeing-memory-vtksmartpointer-vtkimagedata-nifty/4736)

<div class="topic-metadata">

**Author:** [@IVarha](https://discourse.vtk.org/u/IVarha)\
**Replies:** 2\
**Last updated:** [November 26, 2020, 10:59am UTC](https://discourse.vtk.org/t/sigsegv-segmentation-fault-on-freeing-memory-vtksmartpointer-vtkimagedata-nifty/4736 "2020-11-26T10:59:44Z")

</div>

Hello support comumity, I have Segmentation fault error when I am freeing memory. (I use nifty reader to get an image) Here how my parts of source code look like : class NiftiImage { private: vtkSmartPointer niimg …

---

## [Linux VTK Build error: The version of Python is unknown](https://discourse.vtk.org/t/linux-vtk-build-error-the-version-of-python-is-unknown/3899)

<div class="topic-metadata">

**Author:** [@wsherman](https://discourse.vtk.org/u/wsherman)\
**Replies:** 1\
**Last updated:** [November 25, 2020, 10:42pm UTC](https://discourse.vtk.org/t/linux-vtk-build-error-the-version-of-python-is-unknown/3899 "2020-11-25T22:42:44Z")

</div>

Hello, I’m attempting to do a VTK build using the source within the ParaView 5.8.1-RC1 source download. I’m encountering several errors, but I’ll stick with one per discussion thread. I’m building on “CentOS Linux r…

---

## [How can I fix a build error?](https://discourse.vtk.org/t/how-can-i-fix-a-build-error/4690)

<div class="topic-metadata">

**Author:** [@nia38](https://discourse.vtk.org/u/nia38)\
**Replies:** 5\
**Last updated:** [November 25, 2020, 10:14pm UTC](https://discourse.vtk.org/t/how-can-i-fix-a-build-error/4690 "2020-11-25T22:14:08Z")

</div>

VS2019 is in use, and you are trying to build VTK-9.0.1 with Cmake. The following error occurs when Cmake is run: How should I handle this?

---

## [png images can't show to renderwindow](https://discourse.vtk.org/t/png-images-cant-show-to-renderwindow/4722)

<div class="topic-metadata">

**Author:** [@Lisa](https://discourse.vtk.org/u/Lisa)\
**Replies:** 1\
**Last updated:** [November 25, 2020, 10:04pm UTC](https://discourse.vtk.org/t/png-images-cant-show-to-renderwindow/4722 "2020-11-25T22:04:50Z")

</div>

Based on vtk8.2.0,use vtkImageActor and vtkPNGReader to render png images,but png images can’t show to renderwindow On some machines.

---

## [build errors on Raspberry Pi 64bit beta OS - for use with AppCSXCAD](https://discourse.vtk.org/t/build-errors-on-raspberry-pi-64bit-beta-os-for-use-with-appcsxcad/3724)

<div class="topic-metadata">

**Author:** [@Simon\_M](https://discourse.vtk.org/u/Simon_M)\
**Replies:** 1\
**Last updated:** [November 25, 2020, 7:26pm UTC](https://discourse.vtk.org/t/build-errors-on-raspberry-pi-64bit-beta-os-for-use-with-appcsxcad/3724 "2020-11-25T19:26:30Z")

</div>

Hello everyone, please go easy on me - I’m pretty new to building anything on Linux (mainly low level embedded stuff) and I don’t know what information is required to make a question post that people can engage with. I’l…

---

## [Building OpenCascade 7.5.0 with VTK 9.0.1](https://discourse.vtk.org/t/building-opencascade-7-5-0-with-vtk-9-0-1/4673)

<div class="topic-metadata">

**Author:** [@Richard\_Shaw](https://discourse.vtk.org/u/Richard_Shaw)\
**Replies:** 22\
**Last updated:** [November 25, 2020, 4:19pm UTC](https://discourse.vtk.org/t/building-opencascade-7-5-0-with-vtk-9-0-1/4673 "2020-11-25T16:19:01Z")

</div>

OCC 7.4 did not support vtk 9.x at all, but we made a bit of progress trying to build with 7.5.0 until here: \[ 90%\] Building CXX object src/TKIVtkDraw/CMakeFiles/TKIVtkDraw.dir/\_\_/IVtkDraw/IVtkDraw.cxx.o cd /builddir/bu…

---

## [Get Interpolated image value for (x,y,z) point coordinate (BSpline)](https://discourse.vtk.org/t/get-interpolated-image-value-for-x-y-z-point-coordinate-bspline/4726)

<div class="topic-metadata">

**Author:** [@IVarha](https://discourse.vtk.org/u/IVarha)\
**Replies:** 3\
**Last updated:** [November 25, 2020, 3:35pm UTC](https://discourse.vtk.org/t/get-interpolated-image-value-for-x-y-z-point-coordinate-bspline/4726 "2020-11-25T15:35:54Z")

</div>

Hello vtk Support community, I am using vtk for processing of 3d Nifti images and want to get interpolated value from (x,y,z)- I entered them in voxel coordinate space. W this-\>bspline\_coeff = vtkSmartPointer::New(); …

---

## [How to draw rectangle where the specific position?](https://discourse.vtk.org/t/how-to-draw-rectangle-where-the-specific-position/4729)

<div class="topic-metadata">

**Author:** [@nia38](https://discourse.vtk.org/u/nia38)\
**Replies:** 0\
**Last updated:** [November 25, 2020, 2:31am UTC](https://discourse.vtk.org/t/how-to-draw-rectangle-where-the-specific-position/4729 "2020-11-25T02:31:18Z")

</div>

Hello, I used VS2019 and vtk-8.9 version. My plan is that: When the slide Bar(by using mfc component) is changing, drawing the rectangle on image viewer with slide bar’s value(the y-axis value). So, I referred the Bo…

---

## [read data array with integral types from file?](https://discourse.vtk.org/t/read-data-array-with-integral-types-from-file/4680)

<div class="topic-metadata">

**Author:** [@wenyan4work](https://discourse.vtk.org/u/wenyan4work)\
**Replies:** 4\
**Last updated:** [November 24, 2020, 6:45pm UTC](https://discourse.vtk.org/t/read-data-array-with-integral-types-from-file/4680 "2020-11-24T18:45:23Z")

</div>

I’m trying to write a simple file reader to load the int32 and int64 data fields from a polydata file, with name ‘gid’. The VTK document (https://vtk.org/Wiki/VTK/Tutorials/DataArrays#vtkDataArray) says the old API conve…

---

## [Bug in vtkMultiBlockPLOT3DReader](https://discourse.vtk.org/t/bug-in-vtkmultiblockplot3dreader/4650)

<div class="topic-metadata">

**Author:** [@celynchgt](https://discourse.vtk.org/u/celynchgt)\
**Replies:** 3\
**Last updated:** [November 24, 2020, 1:36am UTC](https://discourse.vtk.org/t/bug-in-vtkmultiblockplot3dreader/4650 "2020-11-24T01:36:05Z")

</div>

There appears to be a bug in vtkMultiBlockPLOT3DReader, specifically in the way it guesses the format of the file. I’m using whatever version of VTK is distributed with ParaView 5.8.1. First, I try to read the file wit…

---

## [UWP (C++) Render Window Wrapper](https://discourse.vtk.org/t/uwp-c-render-window-wrapper/3995)

<div class="topic-metadata">

**Author:** [@Ugur](https://discourse.vtk.org/u/Ugur)\
**Replies:** 5\
**Last updated:** [November 19, 2020, 3:11pm UTC](https://discourse.vtk.org/t/uwp-c-render-window-wrapper/3995 "2020-11-19T15:11:58Z")

</div>

Hi everybody, I am new to VTK and currently working with Qt and QVTKOpenGLNativeWidget. Everything works as expected. My question is that, is there also a wrapper for UWP (C++) platform? Kind regards Ugur

---

## [some question](https://discourse.vtk.org/t/some-question/4717)

<div class="topic-metadata">

**Author:** [@cuger\_k](https://discourse.vtk.org/u/cuger_k)\
**Replies:** 0\
**Last updated:** [November 23, 2020, 12:54pm UTC](https://discourse.vtk.org/t/some-question/4717 "2020-11-23T12:54:03Z")

</div>

When I run the provided examples such as DelimitedTextReader，I found that Skipping DelimitedTextReader in the cmake. How can I solve it

---

## [Regarding how to modify image point/cell data](https://discourse.vtk.org/t/regarding-how-to-modify-image-point-cell-data/4714)

<div class="topic-metadata">

**Author:** [@semimodeling](https://discourse.vtk.org/u/semimodeling)\
**Replies:** 0\
**Last updated:** [November 23, 2020, 7:25am UTC](https://discourse.vtk.org/t/regarding-how-to-modify-image-point-cell-data/4714 "2020-11-23T07:25:33Z")

</div>

Dear all, I am new to VTK and I want to ask a question regarding how to modify point and cell data. I am not very familiar with all the concepts yet, so please forgive me if I made any mistakes regarding the naming of o…

---

## [How bind texture to a sampler?](https://discourse.vtk.org/t/how-bind-texture-to-a-sampler/4709)

<div class="topic-metadata">

**Author:** [@Jone7](https://discourse.vtk.org/u/Jone7)\
**Replies:** 2\
**Last updated:** [November 23, 2020, 2:32am UTC](https://discourse.vtk.org/t/how-bind-texture-to-a-sampler/4709 "2020-11-23T02:32:46Z")

</div>

I use AddFragmentShaderReplacement for fragment shader added “uniform sampler2D s”, Can someone tell me how to bind a texture to “sampler2D s” in VTK?

---

## [How to find convex hull of a set of 3D points？](https://discourse.vtk.org/t/how-to-find-convex-hull-of-a-set-of-3d-points/4591)

<div class="topic-metadata">

**Author:** [@WangZP10969](https://discourse.vtk.org/u/WangZP10969)\
**Replies:** 5\
**Last updated:** [November 22, 2020, 1:14pm UTC](https://discourse.vtk.org/t/how-to-find-convex-hull-of-a-set-of-3d-points/4591 "2020-11-22T13:14:48Z")

</div>

How to find the convex hull of a set of 3D points? I did not find a method in the VTK class. Similar functions are vtkHull and vtkPointsProjectedHull, but from the description it is not a way to obtain a set of 3D point …

---

## [how to you pass the STL as a parameter in PyTHON using the Argarse module](https://discourse.vtk.org/t/how-to-you-pass-the-stl-as-a-parameter-in-python-using-the-argarse-module/4710)

<div class="topic-metadata">

**Author:** [@wanglongday](https://discourse.vtk.org/u/wanglongday)\
**Replies:** 0\
**Last updated:** [November 21, 2020, 10:10am UTC](https://discourse.vtk.org/t/how-to-you-pass-the-stl-as-a-parameter-in-python-using-the-argarse-module/4710 "2020-11-21T10:10:42Z")

</div>

how to you pass the STL as a parameter in PyTHON using the Argarse module

---

## [How use a 2D array in VTK to produce a 2D texture](https://discourse.vtk.org/t/how-use-a-2d-array-in-vtk-to-produce-a-2d-texture/4701)

<div class="topic-metadata">

**Author:** [@Jone7](https://discourse.vtk.org/u/Jone7)\
**Replies:** 1\
**Last updated:** [November 21, 2020, 1:28am UTC](https://discourse.vtk.org/t/how-use-a-2d-array-in-vtk-to-produce-a-2d-texture/4701 "2020-11-21T01:28:18Z")

</div>

I want to convert an array into a 2D texture and pass it into shader’s uniform sampler2D variable. Is there any good way?

---

## [how to joint twe actor via vtk(python ),](https://discourse.vtk.org/t/how-to-joint-twe-actor-via-vtk-python/4704)

<div class="topic-metadata">

**Author:** [@wanglongday](https://discourse.vtk.org/u/wanglongday)\
**Replies:** 0\
**Last updated:** [November 20, 2020, 1:41pm UTC](https://discourse.vtk.org/t/how-to-joint-twe-actor-via-vtk-python/4704 "2020-11-20T13:41:24Z")

</div>

how to joint twe actor via vtk(python ),for example ,how to joint picture frame and temple,them(twe actor) is made from section.,please,think you!

---

## [Error: ModuleNotFoundError: No module named 'vtkmodules'](https://discourse.vtk.org/t/error-modulenotfounderror-no-module-named-vtkmodules/4515)

<div class="topic-metadata">

**Author:** [@gautam\_kumar\_singh](https://discourse.vtk.org/u/gautam_kumar_singh)\
**Replies:** 3\
**Last updated:** [November 20, 2020, 11:49am UTC](https://discourse.vtk.org/t/error-modulenotfounderror-no-module-named-vtkmodules/4515 "2020-11-20T11:49:01Z")

</div>

Hi @danlipsa My script is working fine from Mac/Windows Terminal. I am able to make exe file using pyinstaller but when i try to run exe file i am getting errors: emphasized text (py37) C:\\Users\\User\\Desktop\\Project\\…

---

## [How to fill the cylinder](https://discourse.vtk.org/t/how-to-fill-the-cylinder/4669)

<div class="topic-metadata">

**Author:** [@wulicheng](https://discourse.vtk.org/u/wulicheng)\
**Replies:** 1\
**Last updated:** [November 19, 2020, 10:45am UTC](https://discourse.vtk.org/t/how-to-fill-the-cylinder/4669 "2020-11-19T10:45:57Z")

</div>

This is a hollow cylinder, How to fill it to be a solid cylinder?

---

## [9.0.0.rc1 ContextOpenGL2 not built](https://discourse.vtk.org/t/9-0-0-rc1-contextopengl2-not-built/2933)

<div class="topic-metadata">

**Author:** [@Yue\_JIN](https://discourse.vtk.org/u/Yue_JIN)\
**Replies:** 10\
**Last updated:** [November 18, 2020, 6:14pm UTC](https://discourse.vtk.org/t/9-0-0-rc1-contextopengl2-not-built/2933 "2020-11-18T18:14:56Z")

</div>

I’ve built 9.0rc1 and use 9.0rc1 to reconfigure my project. But it exists an error: “Could not find the VTK package with the following required components: RenderingContextOpenGL2.” I find that there is no cmake files in…

---

## [Warp exodusII by vector](https://discourse.vtk.org/t/warp-exodusii-by-vector/4617)

<div class="topic-metadata">

**Author:** [@trinitytest](https://discourse.vtk.org/u/trinitytest)\
**Replies:** 1\
**Last updated:** [November 18, 2020, 3:43pm UTC](https://discourse.vtk.org/t/warp-exodusii-by-vector/4617 "2020-11-18T15:43:50Z")

</div>

I am trying to show a deformed mesh that is read in from an exodusII file. The display of the mesh should update the nodal positions by a vector called “DM”. I have been successful showing the undeformed mesh and displ…

---

## [How to make a point cloud?](https://discourse.vtk.org/t/how-to-make-a-point-cloud/4578)

<div class="topic-metadata">

**Author:** [@inhahe](https://discourse.vtk.org/u/inhahe)\
**Replies:** 11\
**Last updated:** [November 18, 2020, 4:45am UTC](https://discourse.vtk.org/t/how-to-make-a-point-cloud/4578 "2020-11-18T04:45:02Z")

</div>

I suck at figuring out large projects; I can’t make heads or tails of the documentation. I don’t understand how people do it. :stuck\_out\_tongue: Basically, I want to know how to make a point cloud in C++. Well, more basi…

---

## [How to anti-alias in vtkRenderWindow](https://discourse.vtk.org/t/how-to-anti-alias-in-vtkrenderwindow/4556)

<div class="topic-metadata">

**Author:** [@carlusst](https://discourse.vtk.org/u/carlusst)\
**Replies:** 15\
**Last updated:** [November 17, 2020, 1:30pm UTC](https://discourse.vtk.org/t/how-to-anti-alias-in-vtkrenderwindow/4556 "2020-11-17T13:30:37Z")

</div>

The vtkRenderWindow contains a collection of vtkRenderers, and parameters that control rendering features such as stereo, anti-aliasing, motion blur and focal depth. I have an image followed. . How could I do it w…

---

## [How to use Press Key events with screenshot](https://discourse.vtk.org/t/how-to-use-press-key-events-with-screenshot/4656)

<div class="topic-metadata">

**Author:** [@Alaa\_Eddine\_MAZOUZ](https://discourse.vtk.org/u/Alaa_Eddine_MAZOUZ)\
**Replies:** 2\
**Last updated:** [November 16, 2020, 5:42pm UTC](https://discourse.vtk.org/t/how-to-use-press-key-events-with-screenshot/4656 "2020-11-16T17:42:29Z")

</div>

Hello, I’m new to VTK and have been trying to work on a small project in c++ to familiarize my self. I create an actor in a scene and I want to take a screenshot of the window when I want using a press key event, I foll…

---

## [Insert Vector Data into vtkPolyData Object?](https://discourse.vtk.org/t/insert-vector-data-into-vtkpolydata-object/4671)

<div class="topic-metadata">

**Author:** [@ksh\_co](https://discourse.vtk.org/u/ksh_co)\
**Replies:** 0\
**Last updated:** [November 16, 2020, 5:35pm UTC](https://discourse.vtk.org/t/insert-vector-data-into-vtkpolydata-object/4671 "2020-11-16T17:35:00Z")

</div>

Hey Simplifying my last post and deleting it I’m using vtk python(8.1.0) in Anaconda. I’ve read polygon data in from .vtp files using vtkXMLPolyDataReader() and have a vtkPolyData object. I would like to update its Cel…

---

## [I want to change the origin of the coordinates](https://discourse.vtk.org/t/i-want-to-change-the-origin-of-the-coordinates/4661)

<div class="topic-metadata">

**Author:** [@Seram](https://discourse.vtk.org/u/Seram)\
**Replies:** 1\
**Last updated:** [November 16, 2020, 7:29am UTC](https://discourse.vtk.org/t/i-want-to-change-the-origin-of-the-coordinates/4661 "2020-11-16T07:29:40Z")

</div>

Hello I want to change the origin of the coordinates, not change the viewing direction. 1 Attachments (28.49 MB) Expiration: 2020-12-15 Target.zip 28.49 MB I want to switch from left to right. What should I do? I…

---

## [Any way to apply sparse matrix in vtkImageData?](https://discourse.vtk.org/t/any-way-to-apply-sparse-matrix-in-vtkimagedata/4654)

<div class="topic-metadata">

**Author:** [@guojunjie4SD](https://discourse.vtk.org/u/guojunjie4SD)\
**Replies:** 5\
**Last updated:** [November 16, 2020, 3:05am UTC](https://discourse.vtk.org/t/any-way-to-apply-sparse-matrix-in-vtkimagedata/4654 "2020-11-16T03:05:46Z")

</div>

I have skull CT images (about 500 images) and detect the skull data to do some test. The CT data is so large, example: 1024 \* 1024 \* 500, about 500 million points. After detecting the skull data, we found the skull data…

---

## [vtkResliceImageViewer lookup table](https://discourse.vtk.org/t/vtkresliceimageviewer-lookup-table/4394)

<div class="topic-metadata">

**Author:** [@ppiorun](https://discourse.vtk.org/u/ppiorun)\
**Replies:** 1\
**Last updated:** [November 15, 2020, 9:53pm UTC](https://discourse.vtk.org/t/vtkresliceimageviewer-lookup-table/4394 "2020-11-15T21:53:37Z")

</div>

Hello, I have a DICOM visualization using my kind of four pane view. Initially I used vtkImageViewer2, but wanted to show reslice cursor, so moved to vtkResliceImageViewer. After processing I want to select certain voxe…

---

## [How to construct subgrids of a set of tetrahedron](https://discourse.vtk.org/t/how-to-construct-subgrids-of-a-set-of-tetrahedron/4658)

<div class="topic-metadata">

**Author:** [@wanyzh](https://discourse.vtk.org/u/wanyzh)\
**Replies:** 0\
**Last updated:** [November 14, 2020, 1:53am UTC](https://discourse.vtk.org/t/how-to-construct-subgrids-of-a-set-of-tetrahedron/4658 "2020-11-14T01:53:43Z")

</div>

Hi, I have a set of tetrahedron elements and based on these host elements, I want to construct dual-elements around the node with hexahedron sectors. Each sector has eight vertices. The vertices are located at the node,…

[Previous page](https://discourse.vtk.org/c/support/6.md?page=114)

[Next page](https://discourse.vtk.org/c/support/6.md?page=116)