# Development **URL:** https://discourse.vtk.org/c/development/7.md?page=7 [Latest](https://discourse.vtk.org/latest.md) · [Categories](https://discourse.vtk.org/categories.md) · [Tags](https://discourse.vtk.org/tags.md) **Page:** 8 --- ## [CMake Error with VTK: "VTK::CommonColor" includes non-existent path](https://discourse.vtk.org/t/cmake-error-with-vtk-vtk-commoncolor-includes-non-existent-path/15179)
**Author:** [@manafpv](https://discourse.vtk.org/u/manafpv)\ **Replies:** 8\ **Last updated:** [January 20, 2025, 12:56pm UTC](https://discourse.vtk.org/t/cmake-error-with-vtk-vtk-commoncolor-includes-non-existent-path/15179 "2025-01-20T12:56:43Z")
Hello, I am encountering the following error when trying to configure a project with CMake using the example code from VTK Cylinder Example: paar-orin1@ubuntu:~/overlay\_cpp/deepstream\_app/CylinderExample/build$ cmake .… --- ## [VTK clip plane](https://discourse.vtk.org/t/vtk-clip-plane/15183)
**Author:** [@Thilina](https://discourse.vtk.org/u/Thilina)\ **Replies:** 0\ **Last updated:** [January 20, 2025, 10:04am UTC](https://discourse.vtk.org/t/vtk-clip-plane/15183 "2025-01-20T10:04:59Z")
Hello, I’m using VTK and the vtkImplicitPlaneWidget2 to interactively manipulate a clipping plane. By default, the plane can rotate freely around all axes, but I want to restrict its rotation to specific planes: X-Y p… --- ## [nlohmann::json and VTK's public API](https://discourse.vtk.org/t/nlohmann-json-and-vtks-public-api/15131)
**Author:** [@dcthomp](https://discourse.vtk.org/u/dcthomp)\ **Replies:** 20\ **Last updated:** [January 17, 2025, 4:41pm UTC](https://discourse.vtk.org/t/nlohmann-json-and-vtks-public-api/15131 "2025-01-17T16:41:05Z")
Problem Statement As has already been discussed, VTK currently exposes nlohmann::json in some of its public API. This works well, but application developers must be aware that if they also link to nlohmann::json it mus… --- ## [pick points and display the details - java + Swing](https://discourse.vtk.org/t/pick-points-and-display-the-details-java-swing/15145)
**Author:** [@abhishek](https://discourse.vtk.org/u/abhishek)\ **Replies:** 0\ **Last updated:** [January 12, 2025, 2:31pm UTC](https://discourse.vtk.org/t/pick-points-and-display-the-details-java-swing/15145 "2025-01-12T14:31:11Z")
How can I pick points in java + swing for a VTK? With vtkPointPicker I am unable to identify the correct X and Y coordinates. vtkRenderWindowInteractor does not clearly specify how to use AddObserver in java. Thanks in … --- ## [The current 3DSlicer only supports Qt5.15 version, which is embarrassing.](https://discourse.vtk.org/t/the-current-3dslicer-only-supports-qt5-15-version-which-is-embarrassing/14841)
**Author:** [@zhuofalin](https://discourse.vtk.org/u/zhuofalin)\ **Replies:** 3\ **Last updated:** [January 10, 2025, 4:21pm UTC](https://discourse.vtk.org/t/the-current-3dslicer-only-supports-qt5-15-version-which-is-embarrassing/14841 "2025-01-10T16:21:35Z")
Hello, every ascetic who passes by, please give me some help :smiling\_face: Some time ago, when I was testing openGL rendering, I felt that the interaction was not smooth. How should I improve this? 3DSlicer seems to o… --- ## [how vtkWidgetEvent effect the interaction?](https://discourse.vtk.org/t/how-vtkwidgetevent-effect-the-interaction/15135)
**Author:** [@1727711853](https://discourse.vtk.org/u/1727711853)\ **Replies:** 0\ **Last updated:** [January 10, 2025, 7:58am UTC](https://discourse.vtk.org/t/how-vtkwidgetevent-effect-the-interaction/15135 "2025-01-10T07:58:13Z")
when i change the vtkWidgetEvent::Select of “this-\>CallbackMapper-\>SetCallbackMethod(vtkCommand::LeftButtonPressEvent, vtkWidgetEvent::Select, this,EllipseWidget::SelectAction);” to vtkWidgetEvent::AddPoint,my program wi… --- ## [vtkMapper Interpolate Scalars Before Mapping does not work as expected](https://discourse.vtk.org/t/vtkmapper-interpolate-scalars-before-mapping-does-not-work-as-expected/9601)
**Author:** [@abner\_water](https://discourse.vtk.org/u/abner_water)\ **Replies:** 12\ **Last updated:** [January 5, 2025, 1:02pm UTC](https://discourse.vtk.org/t/vtkmapper-interpolate-scalars-before-mapping-does-not-work-as-expected/9601 "2025-01-05T13:02:52Z")
vtkUnstructedGrid scalar color does not match when SetInterpolateScalarsBeforeMapping(1) and SetInterpolateScalarsBeforeMapping(0) here is the test code, this vtu file displays right in paraview like this. void ma… --- ## [vtkHyperTreeGridSource htg construction from large descriptor?](https://discourse.vtk.org/t/vtkhypertreegridsource-htg-construction-from-large-descriptor/15064)
**Author:** [@alhom](https://discourse.vtk.org/u/alhom)\ **Replies:** 5\ **Last updated:** [December 31, 2024, 10:00am UTC](https://discourse.vtk.org/t/vtkhypertreegridsource-htg-construction-from-large-descriptor/15064 "2024-12-31T10:00:58Z")
Hello! I’ve been prototyping some implementations of a custom reader for our in-house TB-AMR data format to expose the data as a vtkHyperTreeGrid. Construction of the vtkHyperTreeGrid looks to work fine, albeit a bit sl… --- ## [How does the vtkDistanceWidget follow image translation?](https://discourse.vtk.org/t/how-does-the-vtkdistancewidget-follow-image-translation/15094)
**Author:** [@SeanHan](https://discourse.vtk.org/u/SeanHan)\ **Replies:** 0\ **Last updated:** [December 31, 2024, 12:49am UTC](https://discourse.vtk.org/t/how-does-the-vtkdistancewidget-follow-image-translation/15094 "2024-12-31T00:49:18Z")
Hi all, I found that vtkTextWidget cannot follow image translation or scaling, but vtkDistanceWidget can, so I want to modify the code of vtkTextWidget like vtkDistanceWidget . Thanks! --- ## [WASM Regression tests (file locations)](https://discourse.vtk.org/t/wasm-regression-tests-file-locations/15040)
**Author:** [@Jens\_Munk\_Hansen](https://discourse.vtk.org/u/Jens_Munk_Hansen)\ **Replies:** 5\ **Last updated:** [December 26, 2024, 2:33pm UTC](https://discourse.vtk.org/t/wasm-regression-tests-file-locations/15040 "2024-12-26T14:33:43Z")
I have some experiments with regards to regression tests for WASM. I do the following Use ExternalData\_add\_test and add\_test Autogenerate a node.js script, which can copy data into WASM filesystem and call a function T… --- ## [vtkXMLUnstructuredGridReader can not read binary vtu file correctly](https://discourse.vtk.org/t/vtkxmlunstructuredgridreader-can-not-read-binary-vtu-file-correctly/15060)
**Author:** [@yiman](https://discourse.vtk.org/u/yiman)\ **Replies:** 2\ **Last updated:** [December 24, 2024, 5:44am UTC](https://discourse.vtk.org/t/vtkxmlunstructuredgridreader-can-not-read-binary-vtu-file-correctly/15060 "2024-12-24T05:44:17Z")
I have one vtu file, it has an “AppendedData” section, in this section, it contains the binary data of all cells. I can open this file without any error in paraview(I know this software also uses vtk), but If I try to re… --- ## [How to get the id of points after append filter?](https://discourse.vtk.org/t/how-to-get-the-id-of-points-after-append-filter/15050)
**Author:** [@Northern\_Condor1](https://discourse.vtk.org/u/Northern_Condor1)\ **Replies:** 2\ **Last updated:** [December 23, 2024, 3:32pm UTC](https://discourse.vtk.org/t/how-to-get-the-id-of-points-after-append-filter/15050 "2024-12-23T15:32:32Z")
Hello! I have dataset of composite type, and in order to use my algorithms which work wih Unordered grid, I use vtkAppendFilter. However, I also need some points ids which are stored in scalar in each of the datasets, a… --- ## [new vtkCutter in 9.4 has great performance loss](https://discourse.vtk.org/t/new-vtkcutter-in-9-4-has-great-performance-loss/15006)
**Author:** [@cmodel](https://discourse.vtk.org/u/cmodel)\ **Replies:** 13\ **Last updated:** [December 20, 2024, 5:23pm UTC](https://discourse.vtk.org/t/new-vtkcutter-in-9-4-has-great-performance-loss/15006 "2024-12-20T17:23:10Z")
I have used vtkCutter codes like the following: vtkSmartPointer\ cutFunction = vtkSmartPointer\::New(); cutFunction-\>SetOrigin(origin); cutFunction-\>SetNormal(normal); vtkSmartPointer\ cutte… --- ## [Interpolation in vtkPolyData](https://discourse.vtk.org/t/interpolation-in-vtkpolydata/15043)
**Author:** [@A.M\_Shahpouri](https://discourse.vtk.org/u/A.M_Shahpouri)\ **Replies:** 0\ **Last updated:** [December 18, 2024, 7:51am UTC](https://discourse.vtk.org/t/interpolation-in-vtkpolydata/15043 "2024-12-18T07:51:27Z")
Hi everyone . I want to create an polydata like this :slight\_smile: I created this Polydata by this code : auto appendPolyData = vtkSmartPointer\::New(); for (const auto& slice : contour.Sli… --- ## [How to get the gray scale pointer in one of MPR image?](https://discourse.vtk.org/t/how-to-get-the-gray-scale-pointer-in-one-of-mpr-image/15028)
**Author:** [@SeanHan](https://discourse.vtk.org/u/SeanHan)\ **Replies:** 0\ **Last updated:** [December 16, 2024, 7:23am UTC](https://discourse.vtk.org/t/how-to-get-the-gray-scale-pointer-in-one-of-mpr-image/15028 "2024-12-16T07:23:05Z")
The gray scale is the same as CT value. --- ## [Documentation for vertexMC, normalMC, MCDCMatrix, MVCMatrix.](https://discourse.vtk.org/t/documentation-for-vertexmc-normalmc-mcdcmatrix-mvcmatrix/1883)
**Author:** [@sherinnovation](https://discourse.vtk.org/u/sherinnovation)\ **Replies:** 6\ **Last updated:** [December 11, 2024, 3:49pm UTC](https://discourse.vtk.org/t/documentation-for-vertexmc-normalmc-mcdcmatrix-mvcmatrix/1883 "2024-12-11T15:49:22Z")
Hi, I am starting my shader development in VTK. Earlier, I had some knowledge on the built-in vertex shader variables like gl\_ModelViewMatrix. However, those variables are no longer appearing valid in my python based V… --- ## [override spline widgets behavior](https://discourse.vtk.org/t/override-spline-widgets-behavior/15004)
**Author:** [@sarahh](https://discourse.vtk.org/u/sarahh)\ **Replies:** 0\ **Last updated:** [December 11, 2024, 3:19pm UTC](https://discourse.vtk.org/t/override-spline-widgets-behavior/15004 "2024-12-11T15:19:32Z")
how to disable mouse right click to delete the spline widget points. (left click drags and right clicks deletes the points) --- ## [VTK Variant](https://discourse.vtk.org/t/vtk-variant/14992)
**Author:** [@PratikKarangle](https://discourse.vtk.org/u/PratikKarangle)\ **Replies:** 1\ **Last updated:** [December 9, 2024, 5:31pm UTC](https://discourse.vtk.org/t/vtk-variant/14992 "2024-12-09T17:31:11Z")
I am working with vtkSQLiteDatabase, vtkTable, and vtkVariant. The vtkVariant class provides various methods to convert the data it holds into different formats such as int, float, char, and string. However, when I use t… --- ## [Does shallow copy increase the lifetime of an object?](https://discourse.vtk.org/t/does-shallow-copy-increase-the-lifetime-of-an-object/14974)
**Author:** [@joint](https://discourse.vtk.org/u/joint)\ **Replies:** 1\ **Last updated:** [December 8, 2024, 2:22am UTC](https://discourse.vtk.org/t/does-shallow-copy-increase-the-lifetime-of-an-object/14974 "2024-12-08T02:22:49Z")
Hello! Let s say, I have a filter which is called in a function and is desctructed then the function returns. The function also shallow-copies the filter output to the object of the caller scope. The question is, whet… --- ## [About KeyCode, KeySym, Modifiers, Crossplatform and reliable code](https://discourse.vtk.org/t/about-keycode-keysym-modifiers-crossplatform-and-reliable-code/12598)
**Author:** [@mwestphal](https://discourse.vtk.org/u/mwestphal)\ **Replies:** 13\ **Last updated:** [December 7, 2024, 6:20am UTC](https://discourse.vtk.org/t/about-keycode-keysym-modifiers-crossplatform-and-reliable-code/12598 "2024-12-07T06:20:20Z")
A few months ago I found a very small issue with the XRenderWindowInteractor where I could not trigger ? keysym on my program. This led me to a rabbit hole and an issue that I’m currently fixing here: https://gitlab.kit… --- ## [vtkOpenGLExtensionManager not Available in VTK 9.3 | Qt 6.5.6 |Unable to initialize OpenGL functions after porting to vtk 9 from vtk 4](https://discourse.vtk.org/t/vtkopenglextensionmanager-not-available-in-vtk-9-3-qt-6-5-6-unable-to-initialize-opengl-functions-after-porting-to-vtk-9-from-vtk-4/14953)
**Author:** [@ataban](https://discourse.vtk.org/u/ataban)\ **Replies:** 3\ **Last updated:** [December 6, 2024, 6:42pm UTC](https://discourse.vtk.org/t/vtkopenglextensionmanager-not-available-in-vtk-9-3-qt-6-5-6-unable-to-initialize-opengl-functions-after-porting-to-vtk-9-from-vtk-4/14953 "2024-12-06T18:42:20Z")
Hi , Currently we are using Qt 6.5.6 in our application and thats the main criteria. To use medical images and operations related to those images (pan/zoom/windowing) earlier in qt 5.5 version we were using vtk 4.10 and… --- ## [Cope & Run FourPaneViewer Demo in QtCreator with cmake](https://discourse.vtk.org/t/cope-run-fourpaneviewer-demo-in-qtcreator-with-cmake/14771)
**Author:** [@zhuofalin](https://discourse.vtk.org/u/zhuofalin)\ **Replies:** 3\ **Last updated:** [December 5, 2024, 5:19pm UTC](https://discourse.vtk.org/t/cope-run-fourpaneviewer-demo-in-qtcreator-with-cmake/14771 "2024-12-05T17:19:29Z")
Hello,everyone :sob: can you help me? :saluting\_face: I encountered the following problem when I copied and ran the FourPaneViewer code in Qtcreator today. There are so many \_\_imp\_\_xxxx flags and too many errors make me… --- ## [How to get polygonal cut surface when I want to use vtkCutter with input of vtkUnstructuredGrid](https://discourse.vtk.org/t/how-to-get-polygonal-cut-surface-when-i-want-to-use-vtkcutter-with-input-of-vtkunstructuredgrid/14965)
**Author:** [@cmodel](https://discourse.vtk.org/u/cmodel)\ **Replies:** 0\ **Last updated:** [December 5, 2024, 7:23am UTC](https://discourse.vtk.org/t/how-to-get-polygonal-cut-surface-when-i-want-to-use-vtkcutter-with-input-of-vtkunstructuredgrid/14965 "2024-12-05T07:23:45Z")
I want to cut a point set (which is unstructured grid) with a plane and want to generate a polygonal cut surface. But I checked out the doc, warning says polygons can NOT be generated when the input is vtkPolyData/vtkUn… --- ## [UnstructuredGrid::GetCellLinks() get null value after I upgrade from 8.2 to 9.4](https://discourse.vtk.org/t/unstructuredgrid-getcelllinks-get-null-value-after-i-upgrade-from-8-2-to-9-4/14947)
**Author:** [@cmodel](https://discourse.vtk.org/u/cmodel)\ **Replies:** 4\ **Last updated:** [December 5, 2024, 7:10am UTC](https://discourse.vtk.org/t/unstructuredgrid-getcelllinks-get-null-value-after-i-upgrade-from-8-2-to-9-4/14947 "2024-12-05T07:10:55Z")
As described in the title, I am upgrading from 8.2 to 9.4, all works fine in the codebase of 8.2, which I have the following: mesh is type of vtkPointSet \*, which is argument in the method. vtkUnstructuredGrid \* grid =… --- ## [Detailed analysis of shadows for rectangular render windows](https://discourse.vtk.org/t/detailed-analysis-of-shadows-for-rectangular-render-windows/12912)
**Author:** [@Sean\_Curtis](https://discourse.vtk.org/u/Sean_Curtis)\ **Replies:** 6\ **Last updated:** [December 4, 2024, 1:15am UTC](https://discourse.vtk.org/t/detailed-analysis-of-shadows-for-rectangular-render-windows/12912 "2024-12-04T01:15:39Z")
This relates to #5057 and #12000. Due to recent other needs that had be spelunking around inside VTK’s implementation of shadows, I thought I’d tackle this topic. However, I’ve hit a wall. Starting with the Shadows exam… --- ## [Why is vtkmodules.util.data\_model overriding by default?](https://discourse.vtk.org/t/why-is-vtkmodules-util-data-model-overriding-by-default/14924)
**Author:** [@banesullivan](https://discourse.vtk.org/u/banesullivan)\ **Replies:** 10\ **Last updated:** [December 3, 2024, 3:29pm UTC](https://discourse.vtk.org/t/why-is-vtkmodules-util-data-model-overriding-by-default/14924 "2024-12-03T15:29:55Z")
In VTK 9.4, it looks this the new Python wrappings originally proposed in More pythonic interface / closer to numpy are now the default imposed on all Python VTK users: \>\>\> from vtkmodules.vtkCommonDataModel import vtkP… --- ## [Shock: Switched from UnstructuredGrid to MultiblockDataset, fields disappeared](https://discourse.vtk.org/t/shock-switched-from-unstructuredgrid-to-multiblockdataset-fields-disappeared/14933)
**Author:** [@Northern\_Condor1](https://discourse.vtk.org/u/Northern_Condor1)\ **Replies:** 0\ **Last updated:** [November 29, 2024, 6:45am UTC](https://discourse.vtk.org/t/shock-switched-from-unstructuredgrid-to-multiblockdataset-fields-disappeared/14933 "2024-11-29T06:45:33Z")
Hello dear VTK developers! Could you please explain me the following: before today, I was using vtkDataSetAlgorithm with UnstructuredGrid. And after the empty stage the empty data objects seemed to have contained fi… --- ## [Rendering acceleration in VTK](https://discourse.vtk.org/t/rendering-acceleration-in-vtk/14932)
**Author:** [@Barry](https://discourse.vtk.org/u/Barry)\ **Replies:** 0\ **Last updated:** [November 28, 2024, 12:41pm UTC](https://discourse.vtk.org/t/rendering-acceleration-in-vtk/14932 "2024-11-28T12:41:06Z")
I have a large dataset of structured grids, which now takes hundreds of seconds to create dataset and three hundred seconds to display on the monitor. Is there any way to improve efficiency and shorten the time after Re… --- ## [using vtkActor2D along with vtkImageCanvasSource2D results in wrong color](https://discourse.vtk.org/t/using-vtkactor2d-along-with-vtkimagecanvassource2d-results-in-wrong-color/14864)
**Author:** [@gongwaner](https://discourse.vtk.org/u/gongwaner)\ **Replies:** 4\ **Last updated:** [November 23, 2024, 6:43am UTC](https://discourse.vtk.org/t/using-vtkactor2d-along-with-vtkimagecanvassource2d-results-in-wrong-color/14864 "2024-11-23T06:43:33Z")
Hi, I want to draw a circle on screen, and I don’t want the circle to get rescaled when mouse scrolls(much like a log on screen). I thought I’ll use vtkImageCanvasSource2D to draw the circle, and then use vtkActor2D to … --- ## [How points are numerated in MultiBlock dataset?](https://discourse.vtk.org/t/how-points-are-numerated-in-multiblock-dataset/14909)
**Author:** [@joint](https://discourse.vtk.org/u/joint)\ **Replies:** 0\ **Last updated:** [November 22, 2024, 11:37am UTC](https://discourse.vtk.org/t/how-points-are-numerated-in-multiblock-dataset/14909 "2024-11-22T11:37:29Z")
Hello I have a multiblock dataset, and a combined dataset which I get with Append filter How to numbers of points correspond to each other in these two kinds of representations? Thanks [Previous page](https://discourse.vtk.org/c/development/7.md?page=6) [Next page](https://discourse.vtk.org/c/development/7.md?page=8)