# Latest **URL:** https://discourse.vtk.org/latest.md [Latest](https://discourse.vtk.org/latest.md) · [Categories](https://discourse.vtk.org/categories.md) · [Tags](https://discourse.vtk.org/tags.md) --- ## [Welcome to the VTK Discourse forum!](https://discourse.vtk.org/t/welcome-to-the-vtk-discourse-forum/8)
**Author:** [@system](https://discourse.vtk.org/u/system)\ **Replies:** 0\ **Last updated:** [August 28, 2018, 7:32pm UTC](https://discourse.vtk.org/t/welcome-to-the-vtk-discourse-forum/8 "2018-08-28T19:32:09Z")
Welcome to the VTK discussion forum! The Visualization Toolkit (VTK) is an open-source, cross-platform library for manipulating and displaying scientific data. It comes with state-of-the-art tools for 3D rendering, a sui… --- ## [Changes in VTK lagacy format from V3.0 to V5.0 - causes cell offset error](https://discourse.vtk.org/t/changes-in-vtk-lagacy-format-from-v3-0-to-v5-0-causes-cell-offset-error/16541)
**Author:** [@KimF](https://discourse.vtk.org/u/KimF)\ **Replies:** 8\ **Last updated:** [September 23, 2026, 10:48pm UTC](https://discourse.vtk.org/t/changes-in-vtk-lagacy-format-from-v3-0-to-v5-0-causes-cell-offset-error/16541 "2026-09-23T22:48:45Z")
I’m trying to write a legacy VTK file for an unstructured tetrahedral grid. All of the VTK documentation I can find suggests that the cell linkage block should have a header as follows CELLS \<# cells\> \ **Author:** [@berk.geveci](https://discourse.vtk.org/u/berk.geveci)\ **Replies:** 33\ **Last updated:** [September 23, 2026, 10:08pm UTC](https://discourse.vtk.org/t/gitlab-availability-part-2/16535 "2026-09-23T22:08:04Z") See GitLab availability and preservation of VTK’s community history The full vm on which gitlab.kitware.com is backed up every 12 hours to our local storage in the server room. These are backed up to a raided storage a… --- ## [VTK.js TypeScript support](https://discourse.vtk.org/t/vtk-js-typescript-support/16534)
**Author:** [@BotellaA](https://discourse.vtk.org/u/BotellaA)\ **Replies:** 3\ **Last updated:** [September 23, 2026, 2:47pm UTC](https://discourse.vtk.org/t/vtk-js-typescript-support/16534 "2026-09-23T14:47:26Z")
What is your current policy on TypeScript support? I see partial support. What should I do when using an untyped file? Should I report it to you somewhere? --- ## [VTK 9.7.0 and 10.0.0 Release Planning](https://discourse.vtk.org/t/vtk-9-7-0-and-10-0-0-release-planning/16371)
**Author:** [@mwestphal](https://discourse.vtk.org/u/mwestphal)\ **Replies:** 9\ **Last updated:** [September 23, 2026, 2:42pm UTC](https://discourse.vtk.org/t/vtk-9-7-0-and-10-0-0-release-planning/16371 "2026-09-23T14:42:55Z")
VTK Release Plan As announced in this post, VTK now follows a regular (calendar-based) release plan, but as mentioned in this blog, VTK 10.0 is on the horizon. Expect a minor release in June 2026 with intermediate patc… --- ## [VTKRuledSurface Bug?](https://discourse.vtk.org/t/vtkruledsurface-bug/8102)
**Author:** [@DAsphyxia](https://discourse.vtk.org/u/DAsphyxia)\ **Replies:** 9\ **Last updated:** [September 21, 2026, 5:48pm UTC](https://discourse.vtk.org/t/vtkruledsurface-bug/8102 "2026-09-21T17:48:50Z")
I tried to use vtkRuledSurfaceFilter to extrude a circle along a spline curve, but some error unexpected happened as shown in the figure below.Some triangle cells are just missed after this option and I have tried all th… --- ## [vtkSTLReader fails, when binary STL starts with keyword 'solid'](https://discourse.vtk.org/t/vtkstlreader-fails-when-binary-stl-starts-with-keyword-solid/16539)
**Author:** [@HST](https://discourse.vtk.org/u/HST)\ **Replies:** 3\ **Last updated:** [September 18, 2026, 6:14am UTC](https://discourse.vtk.org/t/vtkstlreader-fails-when-binary-stl-starts-with-keyword-solid/16539 "2026-09-18T06:14:46Z")
In VTK 9.7.0 the vtkSTLReader fails, when a binary STL file starts with the keyword ‘solid’. I used version 9.5.2 before. This version accepted the same file. In the described case, vtkSTLReader::ReadASCIISTL() is calle… --- ## [vtkXOpenGLRenderWindow::DestroyWindow() can deadlock when Finalize() runs from QVTKRenderWindowInteractor.closeEvent()](https://discourse.vtk.org/t/vtkxopenglrenderwindow-destroywindow-can-deadlock-when-finalize-runs-from-qvtkrenderwindowinteractor-closeevent/16515)
**Author:** [@DungTruog](https://discourse.vtk.org/u/DungTruog)\ **Replies:** 1\ **Last updated:** [September 17, 2026, 6:52pm UTC](https://discourse.vtk.org/t/vtkxopenglrenderwindow-destroywindow-can-deadlock-when-finalize-runs-from-qvtkrenderwindowinteractor-closeevent/16515 "2026-09-17T18:52:37Z")
We meet an intermittent SIGSEGV on closing a Qt window that embeds \`QVTKRenderWindowInteractor\`. Confirmed via a core-dump backtrace and by reading \`vtkXOpenGLRenderWindow\`: the vendored interactor only finalizes its ren… --- ## [Windows on ARM (ARM64) CI support for VTK](https://discourse.vtk.org/t/windows-on-arm-arm64-ci-support-for-vtk/16538)
**Author:** [@Harishmcw](https://discourse.vtk.org/u/Harishmcw)\ **Replies:** 2\ **Last updated:** [September 17, 2026, 2:03pm UTC](https://discourse.vtk.org/t/windows-on-arm-arm64-ci-support-for-vtk/16538 "2026-09-17T14:03:04Z")
Hello everyone, We would like to ask about adding Windows on ARM (ARM64) CI support for VTK. Currently, VTK’s Windows CI builds and wheels are x86\_64 only. With the growing adoption of Windows on ARM devices, adding a … --- ## [GitLab availability and preservation of VTK’s community history](https://discourse.vtk.org/t/gitlab-availability-and-preservation-of-vtk-s-community-history/16533)
**Author:** [@banesullivan](https://discourse.vtk.org/u/banesullivan)\ **Replies:** 25\ **Last updated:** [September 16, 2026, 8:18pm UTC](https://discourse.vtk.org/t/gitlab-availability-and-preservation-of-vtk-s-community-history/16533 "2026-09-16T20:18:28Z")
The current reliability of gitlab.kitware.com has me concerned for the project’s rich ~30 year history with countless community discussions and contributions. VTK has become so foundational and impactful that its availa… --- ## [Migration of macOS CI work](https://discourse.vtk.org/t/migration-of-macos-ci-work/16529)
**Author:** [@ben.boeckel](https://discourse.vtk.org/u/ben.boeckel)\ **Replies:** 2\ **Last updated:** [September 16, 2026, 4:08pm UTC](https://discourse.vtk.org/t/migration-of-macos-ci-work/16529 "2026-09-16T16:08:19Z")
Hi, As I’m sure many have noticed, macOS CI testing for VTK has been rough lately. We’ve been in the middle of a transition from running directly on the hardware to instead using VMs to run the jobs. Now that VTK has me… --- ## [How to render coincident cells?](https://discourse.vtk.org/t/how-to-render-coincident-cells/16516)
**Author:** [@raungst](https://discourse.vtk.org/u/raungst)\ **Replies:** 2\ **Last updated:** [September 16, 2026, 3:15pm UTC](https://discourse.vtk.org/t/how-to-render-coincident-cells/16516 "2026-09-16T15:15:03Z")
I sometimes have coincident cells in the same unstructured grid / actor. My problem is that neither one of them renders when this happens. If I hide one of them, the other one shows up. I’ve tried both SetResolveCoincide… --- ## [Trouble in pip installing vtk-osmesa](https://discourse.vtk.org/t/trouble-in-pip-installing-vtk-osmesa/14890)
**Author:** [@natsu\_mizu](https://discourse.vtk.org/u/natsu_mizu)\ **Replies:** 22\ **Last updated:** [September 15, 2026, 1:53am UTC](https://discourse.vtk.org/t/trouble-in-pip-installing-vtk-osmesa/14890 "2026-09-15T01:53:05Z")
I’ve been using vtk-osmesa installed with pip as pip install --extra-index-url https://wheels.vtk.org vtk-osmesa, following this post: Status Update: VTK Python Wheels - Announcements - VTK OS: “Rocky Linux 8.6 (Green … --- ## [Issues using vtkPReflectionFilter](https://discourse.vtk.org/t/issues-using-vtkpreflectionfilter/16530)
**Author:** [@arey505](https://discourse.vtk.org/u/arey505)\ **Replies:** 0\ **Last updated:** [September 11, 2026, 6:44pm UTC](https://discourse.vtk.org/t/issues-using-vtkpreflectionfilter/16530 "2026-09-11T18:44:58Z")
Hello, I am trying to use vtkPReflectionFilter to apply symmetry to a surface mesh and I am unable to remove seam at the reflection plane. Here is the code snippet: vtkNew\ reader; reader-\>SetFileNa… --- ## [Issue with VTK 9.7.0 maven artifacts for Java](https://discourse.vtk.org/t/issue-with-vtk-9-7-0-maven-artifacts-for-java/16528)
**Author:** [@Marco\_Sambin](https://discourse.vtk.org/u/Marco_Sambin)\ **Replies:** 0\ **Last updated:** [September 10, 2026, 5:03pm UTC](https://discourse.vtk.org/t/issue-with-vtk-9-7-0-maven-artifacts-for-java/16528 "2026-09-10T17:03:26Z")
Hi all. I am using the latest VTK 9.7.0 from within my Java 21-based application. I am currently using the following Maven artifacts for both the VTK JAR file and the related native libraries: \ \ **Author:** [@raungst](https://discourse.vtk.org/u/raungst)\ **Replies:** 5\ **Last updated:** [September 4, 2026, 7:54pm UTC](https://discourse.vtk.org/t/line-elements-cause-missing-edges-in-triangle-cells/16521 "2026-09-04T19:54:53Z") This started in VTK 9.6, but is present in 9.7 as well. I’m not sure how pervasive it is, but if I have an unstructured grid with only triangles and lines, the triangles don’t have edges shown. If I don’t have the lines,… --- ## [Last Chance: What's New in vtk-wasm Webinar tomorrow (Spet 3rd)](https://discourse.vtk.org/t/last-chance-whats-new-in-vtk-wasm-webinar-tomorrow-spet-3rd/16522)
**Author:** [@NickBearup](https://discourse.vtk.org/u/NickBearup)\ **Replies:** 0\ **Last updated:** [September 3, 2026, 7:39am UTC](https://discourse.vtk.org/t/last-chance-whats-new-in-vtk-wasm-webinar-tomorrow-spet-3rd/16522 "2026-09-03T07:39:28Z")
This is the last chance to register for the free ‘What’s New in vtk-wasm’ webinar, happening tomorrow, Thursday, September 3rd. From 12:00pm - 1:00pm ET, the vtk-wasm team will cover the latest developments in vtk-wasm,… --- ## [loading vtk in java fails](https://discourse.vtk.org/t/loading-vtk-in-java-fails/15467)
**Author:** [@metamurk](https://discourse.vtk.org/u/metamurk)\ **Replies:** 37\ **Last updated:** [August 27, 2026, 11:51pm UTC](https://discourse.vtk.org/t/loading-vtk-in-java-fails/15467 "2026-08-27T23:51:24Z")
Hello together, I try to load vtk 9.4.1 into java. I have build with wrappings, vtk jar and wrappings dll are build. I copied it al together and try to to call vtkNativeLibrary.LoadAllNativeLibraries();. It fails. Sev… --- ## [About proper distributed AbortCheck](https://discourse.vtk.org/t/about-proper-distributed-abortcheck/16315)
**Author:** [@mwestphal](https://discourse.vtk.org/u/mwestphal)\ **Replies:** 6\ **Last updated:** [August 26, 2026, 8:38am UTC](https://discourse.vtk.org/t/about-proper-distributed-abortcheck/16315 "2026-08-26T08:38:25Z")
Context A few years ago, @Stephen\_Crowell @Christos\_Tsolakis and @berk.geveci led an effort to improve abort mechanism in VTK, this effort was not fully integrated but great point and design were made here: https://git… --- ## [Improving Abort Functionality in VTK](https://discourse.vtk.org/t/improving-abort-functionality-in-vtk/7813)
**Author:** [@Stephen\_Crowell](https://discourse.vtk.org/u/Stephen_Crowell)\ **Replies:** 6\ **Last updated:** [August 26, 2026, 8:36am UTC](https://discourse.vtk.org/t/improving-abort-functionality-in-vtk/7813 "2026-08-26T08:36:59Z")
Currently, the abort mechanism is designed to function only within a single thread when the abort flag is set by an observer of the progress event. This severely limits the usefulness of the functionality as evidenced by… --- ## [Mismatch of points/tuples between vtkmCleanGrid and its VTK-numpy-wrapper](https://discourse.vtk.org/t/mismatch-of-points-tuples-between-vtkmcleangrid-and-its-vtk-numpy-wrapper/16517)
**Author:** [@Bodacious](https://discourse.vtk.org/u/Bodacious)\ **Replies:** 1\ **Last updated:** [August 25, 2026, 4:13pm UTC](https://discourse.vtk.org/t/mismatch-of-points-tuples-between-vtkmcleangrid-and-its-vtk-numpy-wrapper/16517 "2026-08-25T16:13:14Z")
Hello, This post is a repost of https://discourse.paraview.org/t/mismatch-of-points-tuples-between-vtkmcleangrid-and-its-vtk-numpy-wrapper/17698?u=bodacious after @mwestphal proposition. I have a vtkUnstructuredGrid dat… --- ## [What's New in VTK-wasm - Free Release Webinar](https://discourse.vtk.org/t/whats-new-in-vtk-wasm-free-release-webinar/16520)
**Author:** [@NickBearup](https://discourse.vtk.org/u/NickBearup)\ **Replies:** 0\ **Last updated:** [August 25, 2026, 2:55pm UTC](https://discourse.vtk.org/t/whats-new-in-vtk-wasm-free-release-webinar/16520 "2026-08-25T14:55:39Z")
The VTK team at Kitware will be hosting a free webinar on Thursday, September 3 from 12:00pm - 1:00pm ET covering the latest developments in VTK-wasm and how it can be used to bring high-performance VTK rendering directl… --- ## [vtkShaderProperty::AddFragmentShaderReplacement behaves differently in WebAssembly (VTK 9.5.2) compared to native OpenGL](https://discourse.vtk.org/t/vtkshaderproperty-addfragmentshaderreplacement-behaves-differently-in-webassembly-vtk-9-5-2-compared-to-native-opengl/16513)
**Author:** [@HST](https://discourse.vtk.org/u/HST)\ **Replies:** 0\ **Last updated:** [August 17, 2026, 6:28pm UTC](https://discourse.vtk.org/t/vtkshaderproperty-addfragmentshaderreplacement-behaves-differently-in-webassembly-vtk-9-5-2-compared-to-native-opengl/16513 "2026-08-17T18:28:25Z")
Hi, I use vtkShaderProperty::AddFragmentShaderReplacement() to modify the fragment shader. The following shader replacement works correctly in the native OpenGL build, the actor is red. But it has no visible effect in … --- ## [VTK 9.7.0 release](https://discourse.vtk.org/t/vtk-9-7-0-release/16512)
**Author:** [@sankhesh](https://discourse.vtk.org/u/sankhesh)\ **Replies:** 0\ **Last updated:** [August 17, 2026, 3:51pm UTC](https://discourse.vtk.org/t/vtk-9-7-0-release/16512 "2026-08-17T15:51:48Z")
We are excited to announce the release of VTK v9.7.0 - https://www.kitware.com/vtk-9-7-0/ For a feature highlight and a vtk - python API demo, register here to get access to the recorded webinar - https://www.kitware.co… --- ## [VTK::ViewsRendering: new View and Representation classes](https://discourse.vtk.org/t/vtk-new-view-and-representation-classes/16510)
**Author:** [@berk.geveci](https://discourse.vtk.org/u/berk.geveci)\ **Replies:** 6\ **Last updated:** [August 14, 2026, 1:57pm UTC](https://discourse.vtk.org/t/vtk-new-view-and-representation-classes/16510 "2026-08-14T13:57:17Z")
The VTK::ViewsRendering module merged to master last week (!13418). It is the beginning of a view and representation layer for scientific visualization in VTK, and since there is a good deal more to come, we wanted to ex… --- ## [VR updates, some fun demos and a few questions](https://discourse.vtk.org/t/vr-updates-some-fun-demos-and-a-few-questions/16502)
**Author:** [@fraseyboo](https://discourse.vtk.org/u/fraseyboo)\ **Replies:** 5\ **Last updated:** [August 4, 2026, 3:58pm UTC](https://discourse.vtk.org/t/vr-updates-some-fun-demos-and-a-few-questions/16502 "2026-08-04T15:58:33Z")
So the VR functionalities of VTK have always been a bit under realised and so I thought I’d make a quick demo video of the 3D widgets VTK uses working in VR, I implemented an in-VR menu that attaches to the controllers a… --- ## [Colors in VTK have no declared color space, with consequences throughout the codebase](https://discourse.vtk.org/t/colors-in-vtk-have-no-declared-color-space-with-consequences-throughout-the-codebase/16503)
**Author:** [@mhalle](https://discourse.vtk.org/u/mhalle)\ **Replies:** 2\ **Last updated:** [August 4, 2026, 3:26pm UTC](https://discourse.vtk.org/t/colors-in-vtk-have-no-declared-color-space-with-consequences-throughout-the-codebase/16503 "2026-08-04T15:26:53Z")
I’ve been investigating a core VTK issue with colors for a little while now. This issue is pervasive in VTK and VTK.js, and most likely other derived software. Luckily, I think there’s a gradual fix for it. The core is… --- ## [unresolved external symbol "void \_\_cdecl vtkRenderingVolume\_AutoInit\_Construct(void)"](https://discourse.vtk.org/t/unresolved-external-symbol-void-cdecl-vtkrenderingvolume-autoinit-construct-void/16478)
**Author:** [@jsemeda](https://discourse.vtk.org/u/jsemeda)\ **Replies:** 6\ **Last updated:** [August 3, 2026, 1:37pm UTC](https://discourse.vtk.org/t/unresolved-external-symbol-void-cdecl-vtkrenderingvolume-autoinit-construct-void/16478 "2026-08-03T13:37:26Z")
I am getting this error, vtk-9.5, static libs build with VS under WIndows10. I googled the issue, AI suggested that VTK uses dynamic linking to link the rendering backend at runtime and with static linking that does not… --- ## [vtk-wasm webgl crashes with latest vtk-wasm docker images](https://discourse.vtk.org/t/vtk-wasm-webgl-crashes-with-latest-vtk-wasm-docker-images/16492)
**Author:** [@RaMmer](https://discourse.vtk.org/u/RaMmer)\ **Replies:** 10\ **Last updated:** [August 2, 2026, 8:57pm UTC](https://discourse.vtk.org/t/vtk-wasm-webgl-crashes-with-latest-vtk-wasm-docker-images/16492 "2026-08-02T20:57:45Z")
Hi, I have been observing regular vtk-wasm crashes with webgl losing context because of bad memory allocation as shown in the below picture. This was never occurring with the older docker images with version tag 9.6,… --- ## [How can I delete my account?](https://discourse.vtk.org/t/how-can-i-delete-my-account/16487)
**Author:** [@anon92447926](https://discourse.vtk.org/u/anon92447926)\ **Replies:** 3\ **Last updated:** [July 31, 2026, 9:47am UTC](https://discourse.vtk.org/t/how-can-i-delete-my-account/16487 "2026-07-31T09:47:40Z")
I can’t find any button or link to delete my account. How can I delete my account and my personal information? [Next page](https://discourse.vtk.org/latest.md?page=1)