# Support

**URL:** https://discourse.vtk.org/c/support/6.md?page=94

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

**Page:** 95

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## [Drawing perfectly uniform stipple lines.](https://discourse.vtk.org/t/drawing-perfectly-uniform-stipple-lines/6768)

<div class="topic-metadata">

**Author:** [@Seun](https://discourse.vtk.org/u/Seun)\
**Replies:** 15\
**Last updated:** [October 7, 2021, 12:22pm UTC](https://discourse.vtk.org/t/drawing-perfectly-uniform-stipple-lines/6768 "2021-10-07T12:22:33Z")

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Hello everyone, I was wondering if I could get some help with rendering stippled lines. I’m currently using a vtkActor attached to a PolyDataMapper of which I customise the Shader property in order to get the desired ef…

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## [VTK-9.0.3-1 is asserting with a simple cube FEM in FreeCAD](https://discourse.vtk.org/t/vtk-9-0-3-1-is-asserting-with-a-simple-cube-fem-in-freecad/6749)

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**Author:** [@linux\_guy](https://discourse.vtk.org/u/linux_guy)\
**Replies:** 24\
**Last updated:** [October 7, 2021, 12:11am UTC](https://discourse.vtk.org/t/vtk-9-0-3-1-is-asserting-with-a-simple-cube-fem-in-freecad/6749 "2021-10-07T00:11:48Z")

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I’m not sure where to report a bug/issue, so here I am. Full description of the issue is here: https://forum.freecadweb.org/viewtopic.php?f=18&t=62566&p=537350#p537350 How should I proceed ?

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## [How to draw perfectly uniform stipple lines](https://discourse.vtk.org/t/how-to-draw-perfectly-uniform-stipple-lines/6750)

<div class="topic-metadata">

**Author:** [@Seun](https://discourse.vtk.org/u/Seun)\
**Replies:** 0\
**Last updated:** [October 1, 2021, 7:26pm UTC](https://discourse.vtk.org/t/how-to-draw-perfectly-uniform-stipple-lines/6750 "2021-10-01T19:26:55Z")

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Hello everyone, I was wondering if I could get some help with rendering stippled lines. I’m currently using a vtkActor attached to a PolyDataMapper of which I customise the Shader property in order to get the desired ef…

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## [How to pass geo from vtk to netgen & pass mesh from netgen to vtk directly without needing to exporting/read file?](https://discourse.vtk.org/t/how-to-pass-geo-from-vtk-to-netgen-pass-mesh-from-netgen-to-vtk-directly-without-needing-to-exporting-read-file/6766)

<div class="topic-metadata">

**Author:** [@AlexLuya](https://discourse.vtk.org/u/AlexLuya)\
**Replies:** 1\
**Last updated:** [October 5, 2021, 10:41am UTC](https://discourse.vtk.org/t/how-to-pass-geo-from-vtk-to-netgen-pass-mesh-from-netgen-to-vtk-directly-without-needing-to-exporting-read-file/6766 "2021-10-05T10:41:45Z")

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Following code can export meshing result as vtu file from netgen import occ, meshing from ngsolve.utils import \* from vtkmodules.vtkIOXML import vtkXMLUnstructuredGridReader from ngsolve.comp import \* from ngsolve.solv…

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## [Unable to cast from double\* to vtkSmartPointer\<double\>](https://discourse.vtk.org/t/unable-to-cast-from-double-to-vtksmartpointer-double/6723)

<div class="topic-metadata">

**Author:** [@huaweiping](https://discourse.vtk.org/u/huaweiping)\
**Replies:** 6\
**Last updated:** [October 5, 2021, 10:36am UTC](https://discourse.vtk.org/t/unable-to-cast-from-double-to-vtksmartpointer-double/6723 "2021-10-05T10:36:07Z")

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Hi, Today I find a problem about casting a raw pointer to a SmartPointer. I’m actually randomly facing a segmentation fault when just simply allocating vector (which is very rare I guess) and I can’t figure out the reas…

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## [How to manage several polydata at the same time](https://discourse.vtk.org/t/how-to-manage-several-polydata-at-the-same-time/6761)

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**Author:** [@Texas](https://discourse.vtk.org/u/Texas)\
**Replies:** 1\
**Last updated:** [October 4, 2021, 5:10pm UTC](https://discourse.vtk.org/t/how-to-manage-several-polydata-at-the-same-time/6761 "2021-10-04T17:10:37Z")

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Hello, I have a mesh named my\_initial\_mesh with, let say for the example 6 cells named \[0 1 2 3 4 5\] I would like to delete 2 cells and plot the results of both at the same time so i do : my\_troncated\_mesh=my\_mesh m…

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## [positioning and scaling of Actor2D with image](https://discourse.vtk.org/t/positioning-and-scaling-of-actor2d-with-image/6754)

<div class="topic-metadata">

**Author:** [@rdbrn](https://discourse.vtk.org/u/rdbrn)\
**Replies:** 10\
**Last updated:** [October 4, 2021, 2:16pm UTC](https://discourse.vtk.org/t/positioning-and-scaling-of-actor2d-with-image/6754 "2021-10-04T14:16:11Z")

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I’m trying to display a static image in on of the corners of the screen. Like a company logo or some additional information (see Adding a logo-widget · Issue #474 · marcomusy/vedo (github.com)) . Easiest seems to use a …

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## [Export scene](https://discourse.vtk.org/t/export-scene/6731)

<div class="topic-metadata">

**Author:** [@naffrancois](https://discourse.vtk.org/u/naffrancois)\
**Replies:** 2\
**Last updated:** [October 3, 2021, 8:17am UTC](https://discourse.vtk.org/t/export-scene/6731 "2021-10-03T08:17:46Z")

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Dear all, Please forgive me if this question has been already answered, I could not find clear explanations in other threads. I am currently working with a simple java-vtk window in which I do several things like set i…

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## [Converting physical coordinates to id coordinates](https://discourse.vtk.org/t/converting-physical-coordinates-to-id-coordinates/6753)

<div class="topic-metadata">

**Author:** [@ugursasun](https://discourse.vtk.org/u/ugursasun)\
**Replies:** 0\
**Last updated:** [October 2, 2021, 1:12pm UTC](https://discourse.vtk.org/t/converting-physical-coordinates-to-id-coordinates/6753 "2021-10-02T13:12:30Z")

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Hello. I am a beginner VTK user and I need an immediate help. I am working on a extension on an old code. As I understand, I need to give Pick() function id coordinates( back then, code was working properly with id coor…

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## [Vtk point set registration](https://discourse.vtk.org/t/vtk-point-set-registration/2599)

<div class="topic-metadata">

**Author:** [@ShaneKirkbride](https://discourse.vtk.org/u/ShaneKirkbride)\
**Replies:** 11\
**Last updated:** [October 1, 2021, 1:41am UTC](https://discourse.vtk.org/t/vtk-point-set-registration/2599 "2021-10-01T01:41:09Z")

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Does the ICP algorithm support deformable or non-rigid meshes?

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## [Unable to customize mouse gestures in vtkInteractorStyleRubberBand3D](https://discourse.vtk.org/t/unable-to-customize-mouse-gestures-in-vtkinteractorstylerubberband3d/6740)

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**Author:** [@scotsman60](https://discourse.vtk.org/u/scotsman60)\
**Replies:** 0\
**Last updated:** [September 30, 2021, 10:13pm UTC](https://discourse.vtk.org/t/unable-to-customize-mouse-gestures-in-vtkinteractorstylerubberband3d/6740 "2021-09-30T22:13:14Z")

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I’m using Python 3.8 and vtk 9.0.1 and attempting to customize a vtkInteractorStyleRubberBand3D to support custom view manipulation mouse button bindings and support rubber band picking and rubber band zoom. I was previ…

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## [Issues with vtkImageCanvasSource2D](https://discourse.vtk.org/t/issues-with-vtkimagecanvassource2d/6729)

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**Author:** [@kynetyk](https://discourse.vtk.org/u/kynetyk)\
**Replies:** 1\
**Last updated:** [September 30, 2021, 2:20pm UTC](https://discourse.vtk.org/t/issues-with-vtkimagecanvassource2d/6729 "2021-09-30T14:20:02Z")

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Hello! I’m writing a PyQt5 application to draw on medical images using vtkImageCanvasSource2D, however I’m having issues with oriented images. It seems that when I connect a vtkImageCanvasSource2D to a mapper using Get…

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## [Differences in brightness rendering with Xvfb](https://discourse.vtk.org/t/differences-in-brightness-rendering-with-xvfb/6680)

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**Author:** [@ian\_glover](https://discourse.vtk.org/u/ian_glover)\
**Replies:** 1\
**Last updated:** [September 30, 2021, 2:14pm UTC](https://discourse.vtk.org/t/differences-in-brightness-rendering-with-xvfb/6680 "2021-09-30T14:14:47Z")

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I am having a problem with some unit tests we have to check behaviour of our code applying transformations and displaying the results using vtkImageResliceToColors. The test code renders to image and saves the result as…

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## [Problem with vtkLinearExtrusionFilter](https://discourse.vtk.org/t/problem-with-vtklinearextrusionfilter/6721)

<div class="topic-metadata">

**Author:** [@Beheshtian](https://discourse.vtk.org/u/Beheshtian)\
**Replies:** 2\
**Last updated:** [September 29, 2021, 11:39pm UTC](https://discourse.vtk.org/t/problem-with-vtklinearextrusionfilter/6721 "2021-09-29T23:39:12Z")

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Hi all, I wanna create a 3D object from a surface. I’m using vtkLinearExtusionFilter to extrude a surface but when I do that see some holes on extrude output and some bad edges. see the pic below. here is my code: …

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## [Vtkpolydata inside another one](https://discourse.vtk.org/t/vtkpolydata-inside-another-one/6725)

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**Author:** [@Hanxin\_Hua](https://discourse.vtk.org/u/Hanxin_Hua)\
**Replies:** 0\
**Last updated:** [September 29, 2021, 8:06pm UTC](https://discourse.vtk.org/t/vtkpolydata-inside-another-one/6725 "2021-09-29T20:06:59Z")

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Hello Everyone, I have a question. I define two polydata p1 and p2. If p2 is in p1, then I do nothing. If p2 has some part outside p1, then I use vtkBooleanOperationPolyDataFilter to calculate the union of p1 and p2 a…

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## [Trackpad Interactions](https://discourse.vtk.org/t/trackpad-interactions/6598)

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**Author:** [@coffeecup](https://discourse.vtk.org/u/coffeecup)\
**Replies:** 5\
**Last updated:** [September 29, 2021, 4:49pm UTC](https://discourse.vtk.org/t/trackpad-interactions/6598 "2021-09-29T16:49:14Z")

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Hi, I am trying to understand which Events correspond to trackpad events. When I create a vtkSphereWidget and click on it using my Mac trackpad, it lights up - so I know vtk can accept trackpad events. However, when I…

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## [Creating a new vtkDataSet from an existing vtkDataSet](https://discourse.vtk.org/t/creating-a-new-vtkdataset-from-an-existing-vtkdataset/5870)

<div class="topic-metadata">

**Author:** [@huaweiping](https://discourse.vtk.org/u/huaweiping)\
**Replies:** 2\
**Last updated:** [September 29, 2021, 9:01am UTC](https://discourse.vtk.org/t/creating-a-new-vtkdataset-from-an-existing-vtkdataset/5870 "2021-09-29T09:01:51Z")

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Hello, I just met a question about creating a new vtkDataSet from an existing vtkDataSet. I have an original dataset A vtkSmartPointer\<vtkDataSet\> A = CreateDataSetA(); And now I want to create a deepcopy of the DataS…

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## [No Image when slicing along YZ or XZ plane](https://discourse.vtk.org/t/no-image-when-slicing-along-yz-or-xz-plane/6695)

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**Author:** [@Birkl](https://discourse.vtk.org/u/Birkl)\
**Replies:** 2\
**Last updated:** [September 29, 2021, 8:39am UTC](https://discourse.vtk.org/t/no-image-when-slicing-along-yz-or-xz-plane/6695 "2021-09-29T08:39:23Z")

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Hi everyone, I’m currently working on MIPs for the 3 anatomical planes but I ran into some issues with sagittal and frontal. For those two I only get a completely black image as the output. Below is the function to g…

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## [(vtkmodules.vtkImagingCore.vtkImageReslice)0x7f580e63ec20](https://discourse.vtk.org/t/vtkmodules-vtkimagingcore-vtkimagereslice-0x7f580e63ec20/6710)

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**Author:** [@aleena98](https://discourse.vtk.org/u/aleena98)\
**Replies:** 3\
**Last updated:** [September 28, 2021, 1:39pm UTC](https://discourse.vtk.org/t/vtkmodules-vtkimagingcore-vtkimagereslice-0x7f580e63ec20/6710 "2021-09-28T13:39:54Z")

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I am trying to understand a code to generate MIPs for nifti format images could you please help me with: \*\*(vtkmodules.vtkImagingCore.vtkImageReslice)0x7f580e63ec20 \*\* what exactly is this line

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## [VTK\_DIR beginner, hello](https://discourse.vtk.org/t/vtk-dir-beginner-hello/6548)

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**Author:** [@Tod\_Mar](https://discourse.vtk.org/u/Tod_Mar)\
**Replies:** 12\
**Last updated:** [September 8, 2021, 8:55am UTC](https://discourse.vtk.org/t/vtk-dir-beginner-hello/6548 "2021-09-08T08:55:25Z")

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Hi, How do I specify a permanent VTK\_DIR in the makefile or for CMAKE so that I don’t have to keep typing it into CMAKE everytime I try a new example?

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## [How to merge vtk files?](https://discourse.vtk.org/t/how-to-merge-vtk-files/6678)

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**Author:** [@rasunag27](https://discourse.vtk.org/u/rasunag27)\
**Replies:** 7\
**Last updated:** [September 28, 2021, 3:30am UTC](https://discourse.vtk.org/t/how-to-merge-vtk-files/6678 "2021-09-28T03:30:10Z")

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Dear all, I have two vtk files obtained after the simulation that needs to be merged for visualization. I saw a post related to this where vtkAppendPolyData() function is used. I tried in this way, but gave me an error…

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## [How can i apply vtkImageGaussianSmooth function in VTK.js?](https://discourse.vtk.org/t/how-can-i-apply-vtkimagegaussiansmooth-function-in-vtk-js/6703)

<div class="topic-metadata">

**Author:** [@Yuvi-416](https://discourse.vtk.org/u/Yuvi-416)\
**Replies:** 1\
**Last updated:** [September 27, 2021, 3:01pm UTC](https://discourse.vtk.org/t/how-can-i-apply-vtkimagegaussiansmooth-function-in-vtk-js/6703 "2021-09-27T15:01:11Z")

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Hello Everyone, Is there a way to apply the vtkImageGaussianSmooth function in VTK.js? I searched for the example of an image Gaussian function in VTK.js but I couldn’t find it. I was trying to smooth the data before …

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## [The picture suddenly becomes big or small](https://discourse.vtk.org/t/the-picture-suddenly-becomes-big-or-small/6685)

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**Author:** [@yesyesyes](https://discourse.vtk.org/u/yesyesyes)\
**Replies:** 1\
**Last updated:** [September 27, 2021, 12:47pm UTC](https://discourse.vtk.org/t/the-picture-suddenly-becomes-big-or-small/6685 "2021-09-27T12:47:41Z")

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My question is: How do I get a fixed size image? I use a sensor to control the Angle and make VTK image continuously. But the picture gets bigger and smaller. The problem is the same for both 512×512×24-format 3d data a…

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## [Runtime Crashing (Google Colab)](https://discourse.vtk.org/t/runtime-crashing-google-colab/6699)

<div class="topic-metadata">

**Author:** [@aleena98](https://discourse.vtk.org/u/aleena98)\
**Replies:** 0\
**Last updated:** [September 26, 2021, 12:58am UTC](https://discourse.vtk.org/t/runtime-crashing-google-colab/6699 "2021-09-26T00:58:23Z")

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I am trying to run the following code to slice nifti images but the run time keeps crashing: image\_path = “/content/drive/MyDrive/10001.zip (Unzipped Files)/10001/orig/TOF.nii.gz” reader = vtk.vtkNIFTIImageReader() re…

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## [from vtk.util.misc import vtkGetDataRoot](https://discourse.vtk.org/t/from-vtk-util-misc-import-vtkgetdataroot/6698)

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**Author:** [@aleena98](https://discourse.vtk.org/u/aleena98)\
**Replies:** 1\
**Last updated:** [September 25, 2021, 10:55pm UTC](https://discourse.vtk.org/t/from-vtk-util-misc-import-vtkgetdataroot/6698 "2021-09-25T22:55:38Z")

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from vtk.util.misc import vtkGetDataRoot what does this line do?

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## [How do I copy one vtkRenderer to another vtkRenderer?](https://discourse.vtk.org/t/how-do-i-copy-one-vtkrenderer-to-another-vtkrenderer/6697)

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**Author:** [@yesyesyes](https://discourse.vtk.org/u/yesyesyes)\
**Replies:** 0\
**Last updated:** [September 25, 2021, 3:40pm UTC](https://discourse.vtk.org/t/how-do-i-copy-one-vtkrenderer-to-another-vtkrenderer/6697 "2021-09-25T15:40:02Z")

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Hello, I want to copy one vtkRenderer to another vtkRenderer. This is my previous code: vtkSmartPointer\<vtkRenderer\> renderer2 = vtkSmartPointer\<vtkRenderer\>::New(); renderer2-\>AddActor(imgActor); render…

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## [Reducing loading time](https://discourse.vtk.org/t/reducing-loading-time/6606)

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**Author:** [@Tees](https://discourse.vtk.org/u/Tees)\
**Replies:** 11\
**Last updated:** [September 24, 2021, 11:41am UTC](https://discourse.vtk.org/t/reducing-loading-time/6606 "2021-09-24T11:41:24Z")

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I want to work with time-series files in .vti format. The different time steps are in different files. For testing purposes I have the data halfcylinder01.00.vti, halfcylinder05.00.vti and halfcylinder10.00.vti. In a pr…

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## [transforming normals polydata](https://discourse.vtk.org/t/transforming-normals-polydata/6682)

<div class="topic-metadata">

**Author:** [@nomis6432](https://discourse.vtk.org/u/nomis6432)\
**Replies:** 9\
**Last updated:** [September 24, 2021, 7:56am UTC](https://discourse.vtk.org/t/transforming-normals-polydata/6682 "2021-09-24T07:56:17Z")

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I’m trying to transform the points and normals of a polydata but part of the normals are negated after transformation. I transform the normals by multiplying them with the transposed and inverted transformation matrix c…

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## [Polygonal edge data ?](https://discourse.vtk.org/t/polygonal-edge-data/6675)

<div class="topic-metadata">

**Author:** [@Nicholas\_Yue](https://discourse.vtk.org/u/Nicholas_Yue)\
**Replies:** 1\
**Last updated:** [September 23, 2021, 9:55am UTC](https://discourse.vtk.org/t/polygonal-edge-data/6675 "2021-09-23T09:55:29Z")

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Hi, There is vtkPointData for storing data associated with points, is there a corresponding way to store data associated with the edges of polygon/connectivity ? Cheers

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## [vtkTube : Quadrilaterals instead of Triangles ?](https://discourse.vtk.org/t/vtktube-quadrilaterals-instead-of-triangles/6674)

<div class="topic-metadata">

**Author:** [@Nicholas\_Yue](https://discourse.vtk.org/u/Nicholas_Yue)\
**Replies:** 1\
**Last updated:** [September 23, 2021, 9:45am UTC](https://discourse.vtk.org/t/vtktube-quadrilaterals-instead-of-triangles/6674 "2021-09-23T09:45:42Z")

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Hi, Currently, using vtkTube generates triangle mesh/strip Is there a way to influnce vtkTube to generate quads ? Cheers

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