# Development

**URL:** https://discourse.vtk.org/c/development/7.md?page=47

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

**Page:** 48

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## [Paraview Glance: No color mapping when data array name contains colon](https://discourse.vtk.org/t/paraview-glance-no-color-mapping-when-data-array-name-contains-colon/2022)

<div class="topic-metadata">

**Author:** [@lukas](https://discourse.vtk.org/u/lukas)\
**Replies:** 3\
**Last updated:** [November 1, 2019, 7:29pm UTC](https://discourse.vtk.org/t/paraview-glance-no-color-mapping-when-data-array-name-contains-colon/2022 "2019-11-01T19:29:45Z")

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Hello, I have encountered the following problem: When a data array in a vtkjs file contains a colon in the array name (e.g. “Values: A”), the color mapping does not work in Paraview Glance. I.e. the mesh is displayed…

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## [Issue with TubeFilter when setting normals to polydata (vtk.js)](https://discourse.vtk.org/t/issue-with-tubefilter-when-setting-normals-to-polydata-vtk-js/2019)

<div class="topic-metadata">

**Author:** [@anon10073585](https://discourse.vtk.org/u/anon10073585)\
**Replies:** 0\
**Last updated:** [October 31, 2019, 7:17pm UTC](https://discourse.vtk.org/t/issue-with-tubefilter-when-setting-normals-to-polydata-vtk-js/2019 "2019-10-31T19:17:28Z")

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I can set my own normals to a polydata (lines) in vtk.js, and it works fine. But when I try to use a TubeFilter with said polydata, it doesn’t work; I can only generate the tube if I don’t set the normals. The program do…

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## [vtkJSONDataSetWriter crashes when CellData contains StringArray](https://discourse.vtk.org/t/vtkjsondatasetwriter-crashes-when-celldata-contains-stringarray/2005)

<div class="topic-metadata">

**Author:** [@lukas](https://discourse.vtk.org/u/lukas)\
**Replies:** 2\
**Last updated:** [October 31, 2019, 2:56pm UTC](https://discourse.vtk.org/t/vtkjsondatasetwriter-crashes-when-celldata-contains-stringarray/2005 "2019-10-31T14:56:02Z")

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Hello, The vtkJSONDataSetWriter seems to have an issue, when the DataSet contains cell data with non-vtkDataArray (e.g. StringArray). This kind of DataSet causes Paraview to crash during “Export Scene”. Here is the tes…

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## [Remote modules vs external modules](https://discourse.vtk.org/t/remote-modules-vs-external-modules/2003)

<div class="topic-metadata">

**Author:** [@dgobbi](https://discourse.vtk.org/u/dgobbi)\
**Replies:** 12\
**Last updated:** [October 30, 2019, 8:17pm UTC](https://discourse.vtk.org/t/remote-modules-vs-external-modules/2003 "2019-10-30T20:17:29Z")

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Over the weekend, I started updating vtk-dicom to the new VTK 9 build system. For previous versions of VTK, it was possible to build vtk-dicom either as part of the VTK build (i.e. as a remote module, thanks to Bill Lor…

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## [Add an existing library to a VTK module](https://discourse.vtk.org/t/add-an-existing-library-to-a-vtk-module/2008)

<div class="topic-metadata">

**Author:** [@cobo](https://discourse.vtk.org/u/cobo)\
**Replies:** 2\
**Last updated:** [October 30, 2019, 6:20pm UTC](https://discourse.vtk.org/t/add-an-existing-library-to-a-vtk-module/2008 "2019-10-30T18:20:48Z")

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In a project I am generating a VTK module with vtk\_module\_add\_module(), to be built from a number of source files, and also to be linked with other modules with vtk\_module\_link(): one other self-built module, plus some Q…

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## [SetOpacity is not working correctly!](https://discourse.vtk.org/t/setopacity-is-not-working-correctly/1994)

<div class="topic-metadata">

**Author:** [@rai-sam](https://discourse.vtk.org/u/rai-sam)\
**Replies:** 6\
**Last updated:** [October 30, 2019, 2:41pm UTC](https://discourse.vtk.org/t/setopacity-is-not-working-correctly/1994 "2019-10-30T14:41:33Z")

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I am trying to set opacity for vtkActor but any value less than 1.0 makes it invisible completely. Opacity test example is working fine. What I am missing here? Using vtk 8.2.0.

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## [vtkexodusII project build faild](https://discourse.vtk.org/t/vtkexodusii-project-build-faild/1997)

<div class="topic-metadata">

**Author:** [@james](https://discourse.vtk.org/u/james)\
**Replies:** 5\
**Last updated:** [October 30, 2019, 2:20pm UTC](https://discourse.vtk.org/t/vtkexodusii-project-build-faild/1997 "2019-10-30T14:20:59Z")

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I got a lot of errors when compiling vtk8.2 on Windows10, all from vtkexodusII project。 vtk\\VTK-8.2.0\\ThirdParty\\exodusII\\vtkexodusII\\src\\ex\_utils.c(1415): error C2065: “func”

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## [Filter to select subset of IDs from vtkUnstructuredGrid](https://discourse.vtk.org/t/filter-to-select-subset-of-ids-from-vtkunstructuredgrid/1993)

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**Author:** [@Aramos](https://discourse.vtk.org/u/Aramos)\
**Replies:** 0\
**Last updated:** [October 28, 2019, 12:17pm UTC](https://discourse.vtk.org/t/filter-to-select-subset-of-ids-from-vtkunstructuredgrid/1993 "2019-10-28T12:17:51Z")

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Hi, I’m trying to apply a filter to only display 2/3 of the cells of a vtkUnstructuredGrid. I’m finding very little documentation about the usage of filters and I’m a bit lost about how to do that. This is the code I’v…

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## [Nightly Python Releases on Anaconda](https://discourse.vtk.org/t/nightly-python-releases-on-anaconda/1739)

<div class="topic-metadata">

**Author:** [@banesullivan](https://discourse.vtk.org/u/banesullivan)\
**Replies:** 5\
**Last updated:** [October 26, 2019, 11:56pm UTC](https://discourse.vtk.org/t/nightly-python-releases-on-anaconda/1739 "2019-10-26T23:56:09Z")

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Would anyone be interested in helping set up an Anaconda recipe to build VTK from the master branch on a nightly/periodic basis to keep the Python wheels up to date with the latest developments in VTK? I’ve also posted …

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## [Update file names with ImageWriter](https://discourse.vtk.org/t/update-file-names-with-imagewriter/1955)

<div class="topic-metadata">

**Author:** [@1111](https://discourse.vtk.org/u/1111)\
**Replies:** 2\
**Last updated:** [October 24, 2019, 4:56am UTC](https://discourse.vtk.org/t/update-file-names-with-imagewriter/1955 "2019-10-24T04:56:51Z")

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Hi, I created a program to save images by key operation. The current problem is to be overwritten because the names saved by keyspress are the same. Every time I press the key, I want to save the file as: slice\_1\_512…

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## [Wrapper hierarchy file](https://discourse.vtk.org/t/wrapper-hierarchy-file/1552)

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**Author:** [@Ron84](https://discourse.vtk.org/u/Ron84)\
**Replies:** 19\
**Last updated:** [October 23, 2019, 10:16pm UTC](https://discourse.vtk.org/t/wrapper-hierarchy-file/1552 "2019-10-23T22:16:15Z")

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Hello @ben.boeckel, I have heard that you are familiar with the wrapper “engine” of VTK and you can help me with a problem of my library. I don’t know how to fix this error: \[ 66%\] Python Wrapping - generating vtkboolP…

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## [Streamlines generation using polydata](https://discourse.vtk.org/t/streamlines-generation-using-polydata/1949)

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**Author:** [@Sathiya\_Moorthy](https://discourse.vtk.org/u/Sathiya_Moorthy)\
**Replies:** 3\
**Last updated:** [October 22, 2019, 5:08pm UTC](https://discourse.vtk.org/t/streamlines-generation-using-polydata/1949 "2019-10-22T17:08:04Z")

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How can i use the vtkStreamtracer to generate a streamline with my polydata Sample code is here: auto poly\_data = GetPolyData(entity); ( This polydata contains Points and Verts) // Here I am setting Veloc…

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## [IsA() errors](https://discourse.vtk.org/t/isa-errors/1916)

<div class="topic-metadata">

**Author:** [@toddy](https://discourse.vtk.org/u/toddy)\
**Replies:** 9\
**Last updated:** [October 15, 2019, 6:59pm UTC](https://discourse.vtk.org/t/isa-errors/1916 "2019-10-15T18:59:02Z")

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There a few places in the VTK code where calling IsA() is flawed. Classes vtkOpenGL2ContextDevice2D, vtkSimpleTransform, vtkXXX do not exist, so the code should either be deleted or the class name changed. Classes vtk…

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## [Include directories and linker dependencies](https://discourse.vtk.org/t/include-directories-and-linker-dependencies/1922)

<div class="topic-metadata">

**Author:** [@toddy](https://discourse.vtk.org/u/toddy)\
**Replies:** 1\
**Last updated:** [October 14, 2019, 2:51pm UTC](https://discourse.vtk.org/t/include-directories-and-linker-dependencies/1922 "2019-10-14T14:51:17Z")

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Can someone please explain where/how additional include directories and library dependencies are added to the VTK modules in the cmake files? Are they loaded from a configuration path/file somewhere?

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## [Saving images with a key press](https://discourse.vtk.org/t/saving-images-with-a-key-press/1839)

<div class="topic-metadata">

**Author:** [@1111](https://discourse.vtk.org/u/1111)\
**Replies:** 13\
**Last updated:** [October 14, 2019, 3:22am UTC](https://discourse.vtk.org/t/saving-images-with-a-key-press/1839 "2019-10-14T03:22:05Z")

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Hi, I am creating a program to save raw data of slice plane by pressing “c” based on KeypressEvents. I was able to create a part that saves the raw data by pressing a key, but I don’t know how to adapt the cutout plane…

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## [How can i calculate the surface area of a boundaryEdges?](https://discourse.vtk.org/t/how-can-i-calculate-the-surface-area-of-a-boundaryedges/1915)

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**Author:** [@Matthijs\_Hendriks](https://discourse.vtk.org/u/Matthijs_Hendriks)\
**Replies:** 5\
**Last updated:** [October 11, 2019, 10:55pm UTC](https://discourse.vtk.org/t/how-can-i-calculate-the-surface-area-of-a-boundaryedges/1915 "2019-10-11T22:55:36Z")

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I have the following code. Get a 0 value for the surface area. Is the slice of the boundaryEdges to small? If yess, how do you solve the slice thickness? boundaryEdges = vtk.vtkFeatureEdges() boundaryEdges.SetIn…

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## [What is best way to get the highest point (z-axis) in a polydata?](https://discourse.vtk.org/t/what-is-best-way-to-get-the-highest-point-z-axis-in-a-polydata/1833)

<div class="topic-metadata">

**Author:** [@Matthijs\_Hendriks](https://discourse.vtk.org/u/Matthijs_Hendriks)\
**Replies:** 5\
**Last updated:** [October 11, 2019, 8:13pm UTC](https://discourse.vtk.org/t/what-is-best-way-to-get-the-highest-point-z-axis-in-a-polydata/1833 "2019-10-11T20:13:40Z")

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Is it possible to get the highest point (z-axis) in a polydata. The GetBound() function in vtkActor is not usefull because it only give the boundary

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## [vtk Boolean Operation Poly Data Filter](https://discourse.vtk.org/t/vtk-boolean-operation-poly-data-filter/1476)

<div class="topic-metadata">

**Author:** [@at123](https://discourse.vtk.org/u/at123)\
**Replies:** 7\
**Last updated:** [October 9, 2019, 3:17am UTC](https://discourse.vtk.org/t/vtk-boolean-operation-poly-data-filter/1476 "2019-10-09T03:17:51Z")

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Hello, I have a vtkBooleanOperationPolyDataFilter and I want to add two polydata. I keep getting this error: Input port 0 of algorithm vtkBooleanOperationPolyDataFilter(0x7fd03000e4e0) has 0 connections but is not opti…

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## [Building VTK modules with dependencies results in race condition in make](https://discourse.vtk.org/t/building-vtk-modules-with-dependencies-results-in-race-condition-in-make/1711)

<div class="topic-metadata">

**Author:** [@lhofmann](https://discourse.vtk.org/u/lhofmann)\
**Replies:** 7\
**Last updated:** [October 8, 2019, 3:10pm UTC](https://discourse.vtk.org/t/building-vtk-modules-with-dependencies-results-in-race-condition-in-make/1711 "2019-10-08T15:10:28Z")

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I have a project that builds multiple VTK modules, and some depend on other modules built in the same project. There seems to be some kind of race condition in the resulting Makefiles, that causes an error if a module Mo…

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## [Unfold types and function on vtk.org](https://discourse.vtk.org/t/unfold-types-and-function-on-vtk-org/1819)

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**Author:** [@Charles\_Gueunet](https://discourse.vtk.org/u/Charles_Gueunet)\
**Replies:** 4\
**Last updated:** [October 7, 2019, 2:08am UTC](https://discourse.vtk.org/t/unfold-types-and-function-on-vtk-org/1819 "2019-10-07T02:08:25Z")

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Hello, There is a bug on the current vtk website, I can’t unfold Public Types, Public Member Functions and other list on my browser when browsing the documentation (example here). Clicking on the triangle has no effect…

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## [vtkLight to follow camera facing](https://discourse.vtk.org/t/vtklight-to-follow-camera-facing/1855)

<div class="topic-metadata">

**Author:** [@rai-sam](https://discourse.vtk.org/u/rai-sam)\
**Replies:** 3\
**Last updated:** [October 4, 2019, 9:46am UTC](https://discourse.vtk.org/t/vtklight-to-follow-camera-facing/1855 "2019-10-04T09:46:11Z")

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I have disabled automatic light generation. And want to use vtkLight to update light facing as camera. LightFollowCameraOn is not helping out.

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## [Seg fault in Rendering/OpenGL2/vtkOpenGLTexture.cxx 8.2.0](https://discourse.vtk.org/t/seg-fault-in-rendering-opengl2-vtkopengltexture-cxx-8-2-0/1789)

<div class="topic-metadata">

**Author:** [@efahl](https://discourse.vtk.org/u/efahl)\
**Replies:** 7\
**Last updated:** [October 3, 2019, 7:33pm UTC](https://discourse.vtk.org/t/seg-fault-in-rendering-opengl2-vtkopengltexture-cxx-8-2-0/1789 "2019-10-03T19:33:52Z")

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I’d been chasing a seg fault for some months now, trying to come up with a small reproducible test, but haven’t been able to trim it down to less that 100Ks of lines of code. I passed it off to a colleague who was looki…

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## [integrate HAVS algorithm with OpenGL2 rendering background](https://discourse.vtk.org/t/integrate-havs-algorithm-with-opengl2-rendering-background/1824)

<div class="topic-metadata">

**Author:** [@fanfanliangliang](https://discourse.vtk.org/u/fanfanliangliang)\
**Replies:** 0\
**Last updated:** [September 26, 2019, 12:46am UTC](https://discourse.vtk.org/t/integrate-havs-algorithm-with-opengl2-rendering-background/1824 "2019-09-26T00:46:49Z")

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Hello community , We are affected by a fatal issue on VTK8.0 . If we build VTK8.0 with OpenGL(rendering background), there are some classes about HAVS algorithm (such like vtkHAVSVolumeMapper) built successfully. But w…

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## [Exporting images by key operation.](https://discourse.vtk.org/t/exporting-images-by-key-operation/1756)

<div class="topic-metadata">

**Author:** [@1111](https://discourse.vtk.org/u/1111)\
**Replies:** 4\
**Last updated:** [September 24, 2019, 10:40am UTC](https://discourse.vtk.org/t/exporting-images-by-key-operation/1756 "2019-09-24T10:40:33Z")

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Hi, Currently, I am developing imaging using vtkImplicitPlaneWidget2. I’m thinking about saving to my file by pressing a certain key on the window. First, identify the keys and create code to operate them. Can you gi…

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## [Is there a way to compile on the fly new classes inheriting a VTK class in python?](https://discourse.vtk.org/t/is-there-a-way-to-compile-on-the-fly-new-classes-inheriting-a-vtk-class-in-python/1806)

<div class="topic-metadata">

**Author:** [@Yohann\_Bearzi](https://discourse.vtk.org/u/Yohann_Bearzi)\
**Replies:** 2\
**Last updated:** [September 24, 2019, 3:28am UTC](https://discourse.vtk.org/t/is-there-a-way-to-compile-on-the-fly-new-classes-inheriting-a-vtk-class-in-python/1806 "2019-09-24T03:28:03Z")

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I would need to be able to let users define new classes inheriting an abstract vtk class inheriting vtkDataObject with a few simple methods / static attributes to redefine. Is it possible in python to do this kind of stu…

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## [STL written by vtkSTLWriter is not properly visible in Unity3D!](https://discourse.vtk.org/t/stl-written-by-vtkstlwriter-is-not-properly-visible-in-unity3d/1386)

<div class="topic-metadata">

**Author:** [@rai-sam](https://discourse.vtk.org/u/rai-sam)\
**Replies:** 16\
**Last updated:** [September 12, 2019, 1:57pm UTC](https://discourse.vtk.org/t/stl-written-by-vtkstlwriter-is-not-properly-visible-in-unity3d/1386 "2019-09-12T13:57:54Z")

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Hello, I am new to VTK and interested to make a CAD software. Recently I have been working with decimation. I have tried to write the reduced STL using vtkSTLWriter. But the exported STL is not correctly visible due to …

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## [SetModelTransformMatrix changes the z-coordinate of the translation vector](https://discourse.vtk.org/t/setmodeltransformmatrix-changes-the-z-coordinate-of-the-translation-vector/1738)

<div class="topic-metadata">

**Author:** [@haho](https://discourse.vtk.org/u/haho)\
**Replies:** 0\
**Last updated:** [September 10, 2019, 3:53pm UTC](https://discourse.vtk.org/t/setmodeltransformmatrix-changes-the-z-coordinate-of-the-translation-vector/1738 "2019-09-10T15:53:36Z")

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I just came across the following subtlety: I set the model transform matrix with the command \_curRendererL-\>GetActiveCamera()-\>SetModelTransformMatrix(F\_EA\_L); Then I mark the camera as modified and Render the scene: …

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## [VTK Change of License?](https://discourse.vtk.org/t/vtk-change-of-license/1727)

<div class="topic-metadata">

**Author:** [@lorensen](https://discourse.vtk.org/u/lorensen)\
**Replies:** 3\
**Last updated:** [September 10, 2019, 12:58am UTC](https://discourse.vtk.org/t/vtk-change-of-license/1727 "2019-09-10T00:58:48Z")

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I noticed this MR is changing the VTK License from Apache 2.0 to the 3 clause BSD license. What is the reasoning behind this change? Here is a summary of the differences.

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## [How to update in real time the vtkActor image](https://discourse.vtk.org/t/how-to-update-in-real-time-the-vtkactor-image/1705)

<div class="topic-metadata">

**Author:** [@james](https://discourse.vtk.org/u/james)\
**Replies:** 0\
**Last updated:** [September 5, 2019, 11:55am UTC](https://discourse.vtk.org/t/how-to-update-in-real-time-the-vtkactor-image/1705 "2019-09-05T11:55:31Z")

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I want update in real time the vtkActor form the video capture , thanks for you help!

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## [Synchronize two windows](https://discourse.vtk.org/t/synchronize-two-windows/1703)

<div class="topic-metadata">

**Author:** [@1111](https://discourse.vtk.org/u/1111)\
**Replies:** 0\
**Last updated:** [September 5, 2019, 10:47am UTC](https://discourse.vtk.org/t/synchronize-two-windows/1703 "2019-09-05T10:47:34Z")

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Hi, Currently, we are creating a program that displays the display in vtkImplicitPlaneWidget2 and the plane in vtkImplicitPlaneWidget2 in two dimensions. The display was successful in the two windows. However, when a …

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