# Latest **URL:** https://discourse.vtk.org/latest.md?page=149 [Latest](https://discourse.vtk.org/latest.md) · [Categories](https://discourse.vtk.org/categories.md) · [Tags](https://discourse.vtk.org/tags.md) **Page:** 150 --- ## [VTK's Qt Widget registration with Qt Designer/Creator ?](https://discourse.vtk.org/t/vtks-qt-widget-registration-with-qt-designer-creator/7498)
**Author:** [@Nicholas\_Yue](https://discourse.vtk.org/u/Nicholas_Yue)\ **Replies:** 0\ **Last updated:** [December 24, 2021, 7:33pm UTC](https://discourse.vtk.org/t/vtks-qt-widget-registration-with-qt-designer-creator/7498 "2021-12-24T19:33:15Z")
I have build VTK 9.1.0 from source on Ubuntu 18.0.4 with Qt 5.14.2 I understand there were some changes to naming of Qt related widget in VTK Googling mentioned something called QVTKWidget which is a plugin Qt Creator/… --- ## [Use of Update() in vtk7](https://discourse.vtk.org/t/use-of-update-in-vtk7/7491)
**Author:** [@IT-five](https://discourse.vtk.org/u/IT-five)\ **Replies:** 1\ **Last updated:** [December 24, 2021, 1:32pm UTC](https://discourse.vtk.org/t/use-of-update-in-vtk7/7491 "2021-12-24T13:32:43Z")
read file for geometry reader = vtk.vtkXMLMultiBlockDataReader() reader.SetFileName(geometry\_file) reader.Update() data = reader.GetOutput() data\_iterator = data.NewIterator() img\_data = data\_iterator.GetCurr… --- ## [Code from the pipeline of MDI appllication which worked with 5.8. Need help upgrading it to 9.1](https://discourse.vtk.org/t/code-from-the-pipeline-of-mdi-appllication-which-worked-with-5-8-need-help-upgrading-it-to-9-1/7487)
**Author:** [@Taimour](https://discourse.vtk.org/u/Taimour)\ **Replies:** 4\ **Last updated:** [December 24, 2021, 6:59am UTC](https://discourse.vtk.org/t/code-from-the-pipeline-of-mdi-appllication-which-worked-with-5-8-need-help-upgrading-it-to-9-1/7487 "2021-12-24T06:59:36Z")
Hi Everyone, I am working on a project which includes following code. This code was developed in vtk5.8 and now I am trying to make it work in vtk9.1. The code is compiling but it is not rendering anything. Can Anyone l… --- ## [vtkInteractorStyleRubberBand3D not playing nice with QQuickVTKRenderWindow](https://discourse.vtk.org/t/vtkinteractorstylerubberband3d-not-playing-nice-with-qquickvtkrenderwindow/7478)
**Author:** [@marcwang](https://discourse.vtk.org/u/marcwang)\ **Replies:** 0\ **Last updated:** [December 23, 2021, 4:28am UTC](https://discourse.vtk.org/t/vtkinteractorstylerubberband3d-not-playing-nice-with-qquickvtkrenderwindow/7478 "2021-12-23T04:28:46Z")
I was playing around with QQuickVTKRenderWindow. Instead of a trackball interactor on line 260, I put in a vtkInteractorStyleRubberBand3D. But when I try using it, it throws an error vtkGenericOpenGLRenderWindow (00000… --- ## [Vtk Pipeline Query](https://discourse.vtk.org/t/vtk-pipeline-query/7463)
**Author:** [@Taimour](https://discourse.vtk.org/u/Taimour)\ **Replies:** 1\ **Last updated:** [December 23, 2021, 2:45pm UTC](https://discourse.vtk.org/t/vtk-pipeline-query/7463 "2021-12-23T14:45:37Z")
Hi everyone, I have few queries: Is the pipeline developed in version 5.8 of VTK can work same in vtk 9.1 without any changes? Do we have to worry about the internal structure of pipeline or we can simply use input me… --- ## [GMSH](https://discourse.vtk.org/t/gmsh/3593)
**Author:** [@rdbrn](https://discourse.vtk.org/u/rdbrn)\ **Replies:** 4\ **Last updated:** [December 23, 2021, 1:25pm UTC](https://discourse.vtk.org/t/gmsh/3593 "2021-12-23T13:25:38Z")
Is there a way to import gmsh files into vtk? I did find a gmsh reader in the paraview repo but there does not seem to be such a thing as vtkGmshReader in vtk. --- ## [Are there vtkCylinderSource options for hexagon glyph tiled structuredGrid?](https://discourse.vtk.org/t/are-there-vtkcylindersource-options-for-hexagon-glyph-tiled-structuredgrid/7481)
**Author:** [@Joel\_Mckay](https://discourse.vtk.org/u/Joel_Mckay)\ **Replies:** 0\ **Last updated:** [December 23, 2021, 7:51am UTC](https://discourse.vtk.org/t/are-there-vtkcylindersource-options-for-hexagon-glyph-tiled-structuredgrid/7481 "2021-12-23T07:51:36Z")
The issue with this example is the Rotate in the pipeline causes the whole grid to move on render. Cheers, =) J vtkSmartPointer\ PointToGlyphHexagon(vtkPoints\* points, double const& scale) { auto bounds = p… --- ## [vtkAlgorithm : SetInputConnection() vs AddInputConnection() ?](https://discourse.vtk.org/t/vtkalgorithm-setinputconnection-vs-addinputconnection/7475)
**Author:** [@Nicholas\_Yue](https://discourse.vtk.org/u/Nicholas_Yue)\ **Replies:** 1\ **Last updated:** [December 22, 2021, 11:54pm UTC](https://discourse.vtk.org/t/vtkalgorithm-setinputconnection-vs-addinputconnection/7475 "2021-12-22T23:54:27Z")
I am reading the documentation about the methods here but can’t wrap my head around when to use which one If I am simply connecting the outputport of one node to the inputport of another node, do I add or set ? Cheers --- ## [Dynamically changing opacity in Python with vtkPieceWiseFunction](https://discourse.vtk.org/t/dynamically-changing-opacity-in-python-with-vtkpiecewisefunction/7470)
**Author:** [@ClaraMaria](https://discourse.vtk.org/u/ClaraMaria)\ **Replies:** 0\ **Last updated:** [December 22, 2021, 3:21pm UTC](https://discourse.vtk.org/t/dynamically-changing-opacity-in-python-with-vtkpiecewisefunction/7470 "2021-12-22T15:21:35Z")
Hi! I am trying to figure out if it is possible to modify the vtkPieceWiseFunction, since I am trying to dynamically change the opacity according to a specific formula when using RayCasting. I’m using python 3.8. The f… --- ## [Wrong selection when using polydatamapper-\>SetSelection method.](https://discourse.vtk.org/t/wrong-selection-when-using-polydatamapper-setselection-method/7435)
**Author:** [@yuhaoqiu](https://discourse.vtk.org/u/yuhaoqiu)\ **Replies:** 3\ **Last updated:** [December 22, 2021, 12:17pm UTC](https://discourse.vtk.org/t/wrong-selection-when-using-polydatamapper-setselection-method/7435 "2021-12-22T12:17:00Z")
I’m learning how to use fast pre-select with VTK. I learned that using the SetSelection method of the Mapper class can effectively use the data in the buffer for fast selection. I wrote a demo, but I met some problems. … --- ## [Handling allocation errors in Python](https://discourse.vtk.org/t/handling-allocation-errors-in-python/7451)
**Author:** [@sipkema](https://discourse.vtk.org/u/sipkema)\ **Replies:** 10\ **Last updated:** [December 22, 2021, 10:55am UTC](https://discourse.vtk.org/t/handling-allocation-errors-in-python/7451 "2021-12-22T10:55:57Z")
I ran into what I think might be a bug/regression in vtkFeatureEdges, where the filter tries and fails to allocate a very large array. The following code: from vtkmodules.vtkFiltersCore import vtkFeatureEdges from vtkm… --- ## [After setting the center of the crosshair of the ResliceCursorWidget to empty, there is a problem](https://discourse.vtk.org/t/after-setting-the-center-of-the-crosshair-of-the-reslicecursorwidget-to-empty-there-is-a-problem/7465)
**Author:** [@lanranlaura](https://discourse.vtk.org/u/lanranlaura)\ **Replies:** 1\ **Last updated:** [December 22, 2021, 9:01am UTC](https://discourse.vtk.org/t/after-setting-the-center-of-the-crosshair-of-the-reslicecursorwidget-to-empty-there-is-a-problem/7465 "2021-12-22T09:01:00Z")
Hello! Thanks for your previous help, I now have a new question. I have a requirement that the center of the crosshair of the ResliceCursorWidget should be empty, so I modified the source vtkcylindersource code used in l… --- ## [vtkDataSetMapper vs vtkPolyDataMapper](https://discourse.vtk.org/t/vtkdatasetmapper-vs-vtkpolydatamapper/7404)
**Author:** [@Taimour](https://discourse.vtk.org/u/Taimour)\ **Replies:** 2\ **Last updated:** [December 22, 2021, 7:46am UTC](https://discourse.vtk.org/t/vtkdatasetmapper-vs-vtkpolydatamapper/7404 "2021-12-22T07:46:18Z")
I am working on a project and in my project I have defined mapper as vtkDataSetMapper and my input data is vtkPolyData type. I want to ask, can I use vtkPolyDataMapper with this data? --- ## [VTK 9 Help vtkPolyData GetScalarFieldCriticalIndex](https://discourse.vtk.org/t/vtk-9-help-vtkpolydata-getscalarfieldcriticalindex/7453)
**Author:** [@AlexUtrobin](https://discourse.vtk.org/u/AlexUtrobin)\ **Replies:** 2\ **Last updated:** [December 22, 2021, 7:30am UTC](https://discourse.vtk.org/t/vtk-9-help-vtkpolydata-getscalarfieldcriticalindex/7453 "2021-12-22T07:30:14Z")
Finding critical point in vtkPolyData. Found the GetScalarFieldCriticalIndex method, but the method always returns ERR\_INCORRECT\_FIELD (-3), what am I doing wrong? vtkDoubleArray\* da = dynamic\_cast\(pd-\>G… --- ## [VTK Problems vtkPolyData::GetScalarFieldCriticalIndex](https://discourse.vtk.org/t/vtk-problems-vtkpolydata-getscalarfieldcriticalindex/7461)
**Author:** [@AlexUtrobin](https://discourse.vtk.org/u/AlexUtrobin)\ **Replies:** 0\ **Last updated:** [December 22, 2021, 6:35am UTC](https://discourse.vtk.org/t/vtk-problems-vtkpolydata-getscalarfieldcriticalindex/7461 "2021-12-22T06:35:45Z")
Help! What am I doing wrong? Java code: vtkPolyData pd = new vtkPolyData(); vtkPoints points = new vtkPoints(); points.InsertNextPoint(0, 0, 0); points.InsertNextPoint(5, 0, 0); points.InsertNextPo… --- ## [How generate a set of interest points on a surface from some points.](https://discourse.vtk.org/t/how-generate-a-set-of-interest-points-on-a-surface-from-some-points/7436)
**Author:** [@Miguel\_Socorro](https://discourse.vtk.org/u/Miguel_Socorro)\ **Replies:** 9\ **Last updated:** [December 22, 2021, 2:03am UTC](https://discourse.vtk.org/t/how-generate-a-set-of-interest-points-on-a-surface-from-some-points/7436 "2021-12-22T02:03:24Z")
Hello, I have been able to see in some surgical navigation systems (like Mako for example) selecting some points, the system can generate automatically a broader set of points in places of interest. For example, in this… --- ## [Deprecating \`vtkDataArray::LookupTable\`?](https://discourse.vtk.org/t/deprecating-vtkdataarray-lookuptable/7457)
**Author:** [@Yohann\_Bearzi](https://discourse.vtk.org/u/Yohann_Bearzi)\ **Replies:** 0\ **Last updated:** [December 21, 2021, 8:22pm UTC](https://discourse.vtk.org/t/deprecating-vtkdataarray-lookuptable/7457 "2021-12-21T20:22:03Z")
It seems like vtkDataArray::LookupTable has no use anymore in VTK. Is anyone still using this API, or is it ripe for deprecation? Lookup tables are now dealt with at the mapper level. If you still use this API, please s… --- ## [Pinch gesture on Ubuntu 18.04](https://discourse.vtk.org/t/pinch-gesture-on-ubuntu-18-04/7443)
**Author:** [@syj](https://discourse.vtk.org/u/syj)\ **Replies:** 0\ **Last updated:** [December 21, 2021, 8:49am UTC](https://discourse.vtk.org/t/pinch-gesture-on-ubuntu-18-04/7443 "2021-12-21T08:49:57Z")
Hi guys, I’m trying to use touchscreen on ubuntu 18.04. And my enviroment is as belows: ubuntu 18.04 QT 5.12.9 vtk 9.1 I build the TouchGestureViewer example. Everything works fine, including single-touch, rotate, e… --- ## [How to read TimeValues or write TimeStep](https://discourse.vtk.org/t/how-to-read-timevalues-or-write-timestep/7439)
**Author:** [@olafx](https://discourse.vtk.org/u/olafx)\ **Replies:** 0\ **Last updated:** [December 21, 2021, 6:18am UTC](https://discourse.vtk.org/t/how-to-read-timevalues-or-write-timestep/7439 "2021-12-21T06:18:31Z")
I’m writing time dependent files using the WriteTimeStep(time) function. This makes a TimeValues array in the XML file of whatever times I give. The problem I’m having is that I can’t seem to access TimeValues with the r… --- ## [vtk class for wrapping/handling external command line program](https://discourse.vtk.org/t/vtk-class-for-wrapping-handling-external-command-line-program/7403)
**Author:** [@Nicholas\_Yue](https://discourse.vtk.org/u/Nicholas_Yue)\ **Replies:** 6\ **Last updated:** [December 17, 2021, 8:16am UTC](https://discourse.vtk.org/t/vtk-class-for-wrapping-handling-external-command-line-program/7403 "2021-12-17T08:16:27Z")
I am looking to wrap some external commands in a C++ vtk class for developer’s convenience. What class should I look into ? Some of the external program are generator of information (source), some are filters and some … --- ## [CT reconstruction with variable z spacing (slow interpolation from vtkRectilinearGrid to vtkImageData)](https://discourse.vtk.org/t/ct-reconstruction-with-variable-z-spacing-slow-interpolation-from-vtkrectilineargrid-to-vtkimagedata/7406)
**Author:** [@simonesneault](https://discourse.vtk.org/u/simonesneault)\ **Replies:** 9\ **Last updated:** [December 18, 2021, 3:31pm UTC](https://discourse.vtk.org/t/ct-reconstruction-with-variable-z-spacing-slow-interpolation-from-vtkrectilineargrid-to-vtkimagedata/7406 "2021-12-18T15:31:05Z")
Hello community ! We are trying to handle CT reconstruction with variable z spacing. In order to work with our software, we must obtain a vtkImageData with fixed spacing in all direction. What we are doing for now is t… --- ## [Error building VTK with Python wrappers on Windows](https://discourse.vtk.org/t/error-building-vtk-with-python-wrappers-on-windows/7333)
**Author:** [@toddy](https://discourse.vtk.org/u/toddy)\ **Replies:** 8\ **Last updated:** [December 10, 2021, 10:37pm UTC](https://discourse.vtk.org/t/error-building-vtk-with-python-wrappers-on-windows/7333 "2021-12-10T22:37:01Z")
I’m trying to build VTK with VS2017 and Python wrappers in debug mode and I’m seeing some strange errors. Can someone enlighten me please? --- ## [Cylinder example segv's with VTK-9.1, Mesa-17.3.9, LLVM-6.0.1](https://discourse.vtk.org/t/cylinder-example-segvs-with-vtk-9-1-mesa-17-3-9-llvm-6-0-1/7423)
**Author:** [@biagas](https://discourse.vtk.org/u/biagas)\ **Replies:** 2\ **Last updated:** [December 17, 2021, 11:15pm UTC](https://discourse.vtk.org/t/cylinder-example-segvs-with-vtk-9-1-mesa-17-3-9-llvm-6-0-1/7423 "2021-12-17T23:15:50Z")
On RHEL system, I compiled LLVM (6.0.1) and Mesa (17.3.9) and VTK-9.1.0 (release). I compiled the Cylinder example using the source and CMakeLists.txt from the Examples page When I try to run the Cylinder example I ge… --- ## [Can Someone guide me about using vtkRenderWindowinteractor and vtkwin32renderwinowinteractor?](https://discourse.vtk.org/t/can-someone-guide-me-about-using-vtkrenderwindowinteractor-and-vtkwin32renderwinowinteractor/7414)
**Author:** [@Taimour](https://discourse.vtk.org/u/Taimour)\ **Replies:** 1\ **Last updated:** [December 17, 2021, 10:24pm UTC](https://discourse.vtk.org/t/can-someone-guide-me-about-using-vtkrenderwindowinteractor-and-vtkwin32renderwinowinteractor/7414 "2021-12-17T22:24:57Z")
Can Someone guide me about using vtkRenderWindowinteractor and vtkwin32renderwinowinteractor? I am beginner at vtk libraries. Also I want to know about vtkHandle message2 function. Any help will be appreciated. List … --- ## [Custom event loop for generic render window interactor](https://discourse.vtk.org/t/custom-event-loop-for-generic-render-window-interactor/7415)
**Author:** [@brnk](https://discourse.vtk.org/u/brnk)\ **Replies:** 4\ **Last updated:** [December 17, 2021, 8:40pm UTC](https://discourse.vtk.org/t/custom-event-loop-for-generic-render-window-interactor/7415 "2021-12-17T20:40:50Z")
Hello, I want to implement my own event loop using a vtkGenericRenderWindowInteractor instance. I couldn’t find any examples where the event loop is implemented. The code should have the following structure: #include \ **Author:** [@lehmannt](https://discourse.vtk.org/u/lehmannt)\ **Replies:** 4\ **Last updated:** [December 17, 2021, 5:59pm UTC](https://discourse.vtk.org/t/make-command-fails-on-hello-world-example/7420 "2021-12-17T17:59:27Z") I have installed cmake and VTK from the Kitware instructions. Both installations appeared to go without error. I am attempting to run the C++ Hello World example. I downloaded the downloaded the CylinderExample.tar fi… --- ## [Placing LineWidget & more during ResliceCursorWidget - possible?](https://discourse.vtk.org/t/placing-linewidget-more-during-reslicecursorwidget-possible/7385)
**Author:** [@Hubert\_Z](https://discourse.vtk.org/u/Hubert_Z)\ **Replies:** 4\ **Last updated:** [December 17, 2021, 4:15pm UTC](https://discourse.vtk.org/t/placing-linewidget-more-during-reslicecursorwidget-possible/7385 "2021-12-17T16:15:03Z")
Hi there, I’m adding MPR functionality to an application, and I’d like for my users to be able to place a LineWidget / AngleWidget /… on the different slices created with help of the ResliceCursorWidget. The behavior o… --- ## [Win32 programming: vtkWin32RenderWindowInteractor and message WM\_LBUTTONDOWN](https://discourse.vtk.org/t/win32-programming-vtkwin32renderwindowinteractor-and-message-wm-lbuttondown/7329)
**Author:** [@CharInt0](https://discourse.vtk.org/u/CharInt0)\ **Replies:** 2\ **Last updated:** [December 17, 2021, 3:44pm UTC](https://discourse.vtk.org/t/win32-programming-vtkwin32renderwindowinteractor-and-message-wm-lbuttondown/7329 "2021-12-17T15:44:19Z")
Hi, For a project I am working on, I created a C++/CLI wrapper to a native C++ dll which links the vtk. Then I pass a window handle to the wrapper to create the 3D Canvas inside a C# application (I pass the handle to t… --- ## [vtkmfcview](https://discourse.vtk.org/t/vtkmfcview/7425)
**Author:** [@Taimour](https://discourse.vtk.org/u/Taimour)\ **Replies:** 0\ **Last updated:** [December 17, 2021, 12:47pm UTC](https://discourse.vtk.org/t/vtkmfcview/7425 "2021-12-17T12:47:13Z")
I want to ask that vtmfcview is the same as vtkmdiview? --- ## [Vtk 9.1.0 wants version 8.1.0 of FMT?](https://discourse.vtk.org/t/vtk-9-1-0-wants-version-8-1-0-of-fmt/7417)
**Author:** [@Michael\_Jackson](https://discourse.vtk.org/u/Michael_Jackson)\ **Replies:** 1\ **Last updated:** [December 16, 2021, 3:53pm UTC](https://discourse.vtk.org/t/vtk-9-1-0-wants-version-8-1-0-of-fmt/7417 "2021-12-16T15:53:03Z")
I was trying to build VTK version 9.1 using an external “fmt” library but I am getting a cmake configuration error where VTK wants version 8.1.0 of fmt but such a version does not exist according to the official GitHub r… [Previous page](https://discourse.vtk.org/latest.md?page=148) [Next page](https://discourse.vtk.org/latest.md?page=150)