# Latest **URL:** https://discourse.vtk.org/latest.md?page=106 [Latest](https://discourse.vtk.org/latest.md) · [Categories](https://discourse.vtk.org/categories.md) · [Tags](https://discourse.vtk.org/tags.md) **Page:** 107 --- ## [Changing the interactor style when hovering an actor in VTK python](https://discourse.vtk.org/t/changing-the-interactor-style-when-hovering-an-actor-in-vtk-python/10158)
**Author:** [@Raphael\_Lubaschewski](https://discourse.vtk.org/u/Raphael_Lubaschewski)\ **Replies:** 0\ **Last updated:** [December 11, 2022, 2:12pm UTC](https://discourse.vtk.org/t/changing-the-interactor-style-when-hovering-an-actor-in-vtk-python/10158 "2022-12-11T14:12:26Z")
I want to use the TrackballCamera InteractorStyle when I don’t hover my actor (a cylinder). In the case where the mouse is over the actor, I want to use the TrackballActor InteractorStyle. I know that it is possible to … --- ## [How to perform point cloud slicing via VTK](https://discourse.vtk.org/t/how-to-perform-point-cloud-slicing-via-vtk/10155)
**Author:** [@Dwight98](https://discourse.vtk.org/u/Dwight98)\ **Replies:** 0\ **Last updated:** [December 11, 2022, 1:14pm UTC](https://discourse.vtk.org/t/how-to-perform-point-cloud-slicing-via-vtk/10155 "2022-12-11T13:14:22Z")
I want to perform a uniform slicing operation on the pipe point cloud data through VTK, can it be achieved, if you can hope that the seniors will give the method, thank you a lot！ --- ## [Clip voronoi2D mesh interiors ?](https://discourse.vtk.org/t/clip-voronoi2d-mesh-interiors/10145)
**Author:** [@AndreAhmed](https://discourse.vtk.org/u/AndreAhmed)\ **Replies:** 7\ **Last updated:** [December 11, 2022, 9:51am UTC](https://discourse.vtk.org/t/clip-voronoi2d-mesh-interiors/10145 "2022-12-11T09:51:12Z")
I have the following mesh that I generated from Spline. I would like to clip the mesh at the voronoi cells I used VTKTrimmExtrusion and I get the following output but it doesn’t include the curved surface… --- ## [vtkOBJReader - vtkPolyData grouping access ?](https://discourse.vtk.org/t/vtkobjreader-vtkpolydata-grouping-access/10131)
**Author:** [@Nicholas\_Yue](https://discourse.vtk.org/u/Nicholas_Yue)\ **Replies:** 1\ **Last updated:** [December 10, 2022, 7:27pm UTC](https://discourse.vtk.org/t/vtkobjreader-vtkpolydata-grouping-access/10131 "2022-12-10T19:27:52Z")
When loading a Wavefront OBJ file that has multiple g groups, I noticed that the resulting vtkPolyData when written out as \*.vtp retains some of the grouping structure. I discover those groupings when I loaded the export… --- ## [Render a single slice from a stack without reading the full stack into memory](https://discourse.vtk.org/t/render-a-single-slice-from-a-stack-without-reading-the-full-stack-into-memory/10144)
**Author:** [@Chaitanya\_Kolluru](https://discourse.vtk.org/u/Chaitanya_Kolluru)\ **Replies:** 1\ **Last updated:** [December 10, 2022, 3:51am UTC](https://discourse.vtk.org/t/render-a-single-slice-from-a-stack-without-reading-the-full-stack-into-memory/10144 "2022-12-10T03:51:58Z")
Hi, I have a dataset of 1000 images, with a total size of 11 GB. In my application, I want to render a specific slice in the window based on interactive user input. I’d like to do this in a way that does not involve rea… --- ## [spline to 2D mesh?](https://discourse.vtk.org/t/spline-to-2d-mesh/10142)
**Author:** [@AndreAhmed](https://discourse.vtk.org/u/AndreAhmed)\ **Replies:** 1\ **Last updated:** [December 10, 2022, 3:37am UTC](https://discourse.vtk.org/t/spline-to-2d-mesh/10142 "2022-12-10T03:37:57Z")
Is there a way in VTK to create from an spline a 2DMesh ? --- ## [Best approach for interact with a huge number of objects](https://discourse.vtk.org/t/best-approach-for-interact-with-a-huge-number-of-objects/1179)
**Author:** [@Marcel\_Santos](https://discourse.vtk.org/u/Marcel_Santos)\ **Replies:** 4\ **Last updated:** [December 10, 2022, 3:32am UTC](https://discourse.vtk.org/t/best-approach-for-interact-with-a-huge-number-of-objects/1179 "2022-12-10T03:32:29Z")
Hi VTK developers, I am working on a project that we need to render a huge number of instances of a source (for instance spheres, cones, planes and arrows), similitar to a point cloud. Please, see below a image for pur… --- ## [codeSandbox examples for vtk.js gives error for controller.html](https://discourse.vtk.org/t/codesandbox-examples-for-vtk-js-gives-error-for-controller-html/10141)
**Author:** [@Alireza](https://discourse.vtk.org/u/Alireza)\ **Replies:** 3\ **Last updated:** [December 9, 2022, 8:48pm UTC](https://discourse.vtk.org/t/codesandbox-examples-for-vtk-js-gives-error-for-controller-html/10141 "2022-12-09T20:48:07Z")
Pretty much the title. When I want to add the controller.html to my example in codesandbox, it gives error. Cannot read properties of null (reading 'addEventListener') So basically it doesn’t have document? I couldn… --- ## [Trying boolean operation on a voronoi 2D Mesh](https://discourse.vtk.org/t/trying-boolean-operation-on-a-voronoi-2d-mesh/10139)
**Author:** [@AndreAhmed](https://discourse.vtk.org/u/AndreAhmed)\ **Replies:** 4\ **Last updated:** [December 9, 2022, 7:43pm UTC](https://discourse.vtk.org/t/trying-boolean-operation-on-a-voronoi-2d-mesh/10139 "2022-12-09T19:43:08Z")
Hi, Thanks for your help in advance. I’ve the following two polydata as shown in the figure I’m trying to do boolean operation on them, but it says that the voronoi mesh has non manfiold data, and there is no contact. H… --- ## [VTKVornoi2D doesn't work probably](https://discourse.vtk.org/t/vtkvornoi2d-doesnt-work-probably/10138)
**Author:** [@AndreAhmed](https://discourse.vtk.org/u/AndreAhmed)\ **Replies:** 3\ **Last updated:** [December 9, 2022, 3:41pm UTC](https://discourse.vtk.org/t/vtkvornoi2d-doesnt-work-probably/10138 "2022-12-09T15:41:37Z")
Hello, I have two questions. I’m trying to use VTKVornoi to generate a 2D Mesh of voronoi graph, and the results is like the following picture vtkSmartPointer poly\_voronoi = vtkSmartPointer::New(); int i = 0; wh… --- ## [Plotting time series scalars on a single mesh](https://discourse.vtk.org/t/plotting-time-series-scalars-on-a-single-mesh/10091)
**Author:** [@Reshma\_R\_S](https://discourse.vtk.org/u/Reshma_R_S)\ **Replies:** 3\ **Last updated:** [December 9, 2022, 2:36pm UTC](https://discourse.vtk.org/t/plotting-time-series-scalars-on-a-single-mesh/10091 "2022-12-09T14:36:48Z")
I have a single surface (say, a sphere). For the sphere, I would like to store the scalar named temperature which varies over time. I have data from 1000 time points. Here, I don’t wish to store all the scalar arrays (fr… --- ## [Displaying multiple scalar fields in a single polyData](https://discourse.vtk.org/t/displaying-multiple-scalar-fields-in-a-single-polydata/9345)
**Author:** [@glefloch](https://discourse.vtk.org/u/glefloch)\ **Replies:** 6\ **Last updated:** [December 9, 2022, 7:24am UTC](https://discourse.vtk.org/t/displaying-multiple-scalar-fields-in-a-single-polydata/9345 "2022-12-09T07:24:01Z")
Problem: I would like to display 2 (or more) scalar fields in a single poly data mesh, using a single vtkActor. One scalar field would be mapped to certain cells of the poly data mesh, while the other would be mapped t… --- ## [The feasibility of java calling vtk's c++ dynamic library through JNI and JNA](https://discourse.vtk.org/t/the-feasibility-of-java-calling-vtks-c-dynamic-library-through-jni-and-jna/10116)
**Author:** [@HWsir](https://discourse.vtk.org/u/HWsir)\ **Replies:** 3\ **Last updated:** [December 9, 2022, 5:06am UTC](https://discourse.vtk.org/t/the-feasibility-of-java-calling-vtks-c-dynamic-library-through-jni-and-jna/10116 "2022-12-09T05:06:05Z")
example error --- ## [Slice plot in vtk](https://discourse.vtk.org/t/slice-plot-in-vtk/10130)
**Author:** [@Jishnu](https://discourse.vtk.org/u/Jishnu)\ **Replies:** 0\ **Last updated:** [December 9, 2022, 4:00am UTC](https://discourse.vtk.org/t/slice-plot-in-vtk/10130 "2022-12-09T04:00:38Z")
Hi everyone, I have a polydata file containing 3D coordinates of the mesh (as vtkPoints) and temperature at each point as an attribute. I want to plot the temperature as a slice plot (at three elevations) over the geomet… --- ## [Get the texture color and display in polydata by sliding the mouse](https://discourse.vtk.org/t/get-the-texture-color-and-display-in-polydata-by-sliding-the-mouse/10129)
**Author:** [@ahhhstudy](https://discourse.vtk.org/u/ahhhstudy)\ **Replies:** 0\ **Last updated:** [December 9, 2022, 3:18am UTC](https://discourse.vtk.org/t/get-the-texture-color-and-display-in-polydata-by-sliding-the-mouse/10129 "2022-12-09T03:18:42Z")
I’m a newbie in vtk, I’m facing a problem now, I have a stl model, I have projectedTexture mapping on it, now I’m trying to pass the mouse, read the texture color of the mouse position and display it, I think it should b… --- ## [I want to use vtk for registration visualization](https://discourse.vtk.org/t/i-want-to-use-vtk-for-registration-visualization/10100)
**Author:** [@marlon.ma](https://discourse.vtk.org/u/marlon.ma)\ **Replies:** 12\ **Last updated:** [December 9, 2022, 2:49am UTC](https://discourse.vtk.org/t/i-want-to-use-vtk-for-registration-visualization/10100 "2022-12-09T02:49:22Z")
\#include\ #include\ #include\ #include\ #include\ #include \ #include\ #include\ #include\<… --- ## [How to calculate line line intersection](https://discourse.vtk.org/t/how-to-calculate-line-line-intersection/10108)
**Author:** [@nnzzll](https://discourse.vtk.org/u/nnzzll)\ **Replies:** 3\ **Last updated:** [December 8, 2022, 5:58pm UTC](https://discourse.vtk.org/t/how-to-calculate-line-line-intersection/10108 "2022-12-08T17:58:36Z")
I got 2 lines and each line was defined by two points. I’m trying to compute the intersection of the two lines with code below: img1Line1P1 = \[35.522341272816135, 244.0, -81.8808026069687\] img1Line1P2 = \[36.18009447010… --- ## [vtkAxesTransformWidget doesn't work?](https://discourse.vtk.org/t/vtkaxestransformwidget-doesnt-work/10126)
**Author:** [@Gilthalas](https://discourse.vtk.org/u/Gilthalas)\ **Replies:** 0\ **Last updated:** [December 8, 2022, 3:53pm UTC](https://discourse.vtk.org/t/vtkaxestransformwidget-doesnt-work/10126 "2022-12-08T15:53:51Z")
I’ve tried to implement vtkAxesTransformWidget in some code, and seems to do absolutely nothing. Is there some example code for this class? I’m looking for a widget that will surround an object and allow me to scale, t… --- ## [VTP + Historgram - annotation hints ?](https://discourse.vtk.org/t/vtp-historgram-annotation-hints/10110)
**Author:** [@Nicholas\_Yue](https://discourse.vtk.org/u/Nicholas_Yue)\ **Replies:** 1\ **Last updated:** [December 8, 2022, 2:23pm UTC](https://discourse.vtk.org/t/vtp-historgram-annotation-hints/10110 "2022-12-08T14:23:11Z")
Is there some attribute I can add to my vtkFloatArray that when written out as part of a mesh in a VTP file, may hint to ParaView to us them as axis titles, chart title ? Currently, I a typing them in manually so that t… --- ## [vtkHyperStreamLine usage](https://discourse.vtk.org/t/vtkhyperstreamline-usage/3543)
**Author:** [@Andrea\_Gavana](https://discourse.vtk.org/u/Andrea_Gavana)\ **Replies:** 21\ **Last updated:** [December 8, 2022, 12:59pm UTC](https://discourse.vtk.org/t/vtkhyperstreamline-usage/3543 "2022-12-08T12:59:05Z")
Dear all, Since my previous question went unanswered (https://discourse.vtk.org/t/vtktubefilter-representation-and-intersections/3371) I looked around a little bit and it seems to me that vtkHyperStreamLine could be use… --- ## [\[VTK.js/React\] Unable to smooth ImageData using ImageMarchingCubes and WindowedSyncPolyDataFilter](https://discourse.vtk.org/t/vtk-js-react-unable-to-smooth-imagedata-using-imagemarchingcubes-and-windowedsyncpolydatafilter/10002)
**Author:** [@sanderteirlynck](https://discourse.vtk.org/u/sanderteirlynck)\ **Replies:** 3\ **Last updated:** [December 8, 2022, 7:56am UTC](https://discourse.vtk.org/t/vtk-js-react-unable-to-smooth-imagedata-using-imagemarchingcubes-and-windowedsyncpolydatafilter/10002 "2022-12-08T07:56:12Z")
I’m running into some issues trying to smooth the ImageData coming from a Niftii file. When I render the ImageData without the ImageMarchingCubes and WindowedSyncPolyDataFilter, everything works as expected but the Imag… --- ## [VTK 9.2.2 / OCC 7.6.0 fails at to\_int\_type() function of MSVC when mapping PolyDataSource?](https://discourse.vtk.org/t/vtk-9-2-2-occ-7-6-0-fails-at-to-int-type-function-of-msvc-when-mapping-polydatasource/10073)
**Author:** [@bunny](https://discourse.vtk.org/u/bunny)\ **Replies:** 3\ **Last updated:** [December 8, 2022, 7:18am UTC](https://discourse.vtk.org/t/vtk-9-2-2-occ-7-6-0-fails-at-to-int-type-function-of-msvc-when-mapping-polydatasource/10073 "2022-12-08T07:18:12Z")
It works fine with VTK released libs but fails with debug libs. the libs of VTK that I uses --- ## [VTK8.2.0(& VTK 9.1.0) for android with official Android's example(JavaVTK) not runing exactly](https://discourse.vtk.org/t/vtk8-2-0-vtk-9-1-0-for-android-with-official-androids-example-javavtk-not-runing-exactly/7622)
**Author:** [@user\_1](https://discourse.vtk.org/u/user_1)\ **Replies:** 6\ **Last updated:** [December 8, 2022, 3:34am UTC](https://discourse.vtk.org/t/vtk8-2-0-vtk-9-1-0-for-android-with-official-androids-example-javavtk-not-runing-exactly/7622 "2022-12-08T03:34:57Z")
Hello everyone, I was already build VTK 8.2.0 and VTK 9.1.0 with ndk-r21e and import it into AndroidStudio. I was created 2 projects that one include VTK-8.2.0 and the other include VTK-9.1.0 , and I copy the code whi… --- ## [vtkInteractorObserver::ComputeDisplayToWorld dirties the Renderer!](https://discourse.vtk.org/t/vtkinteractorobserver-computedisplaytoworld-dirties-the-renderer/10111)
**Author:** [@John.Stone](https://discourse.vtk.org/u/John.Stone)\ **Replies:** 0\ **Last updated:** [December 8, 2022, 2:42am UTC](https://discourse.vtk.org/t/vtkinteractorobserver-computedisplaytoworld-dirties-the-renderer/10111 "2022-12-08T02:42:26Z")
So, I’d like to use vtkRenderer::BackingStoreOn() but I just noticed that vtkInteractorObserver::ComputeDisplayToWorld() and vtkInteractorObserver::ComputeWorldToDisplay() mark the passed renderer dirty because they indi… --- ## [Overlaying conflict and depth buffer](https://discourse.vtk.org/t/overlaying-conflict-and-depth-buffer/10107)
**Author:** [@Flagada](https://discourse.vtk.org/u/Flagada)\ **Replies:** 0\ **Last updated:** [December 7, 2022, 11:08pm UTC](https://discourse.vtk.org/t/overlaying-conflict-and-depth-buffer/10107 "2022-12-07T23:08:23Z")
Hi all! For the context my final goal is to display a pressure loading applied on different faces of volumic elements. I have a vtkUnstructuredGrid containing 3D cells (vtkWedge and vtkHexahedron) with some colors set … --- ## [How does the point cloud rendered by vtkPolyData interact with each point?](https://discourse.vtk.org/t/how-does-the-point-cloud-rendered-by-vtkpolydata-interact-with-each-point/10029)
**Author:** [@zhangzhi93](https://discourse.vtk.org/u/zhangzhi93)\ **Replies:** 9\ **Last updated:** [December 7, 2022, 5:44pm UTC](https://discourse.vtk.org/t/how-does-the-point-cloud-rendered-by-vtkpolydata-interact-with-each-point/10029 "2022-12-07T17:44:22Z")
I want to view the point information when clicking each point in the point cloud. How can I get the click event of vtkPoints --- ## [vtkCellData::AddArray() crash in some situation - v9.2.2](https://discourse.vtk.org/t/vtkcelldata-addarray-crash-in-some-situation-v9-2-2/10105)
**Author:** [@Nicholas\_Yue](https://discourse.vtk.org/u/Nicholas_Yue)\ **Replies:** 1\ **Last updated:** [December 7, 2022, 5:29pm UTC](https://discourse.vtk.org/t/vtkcelldata-addarray-crash-in-some-situation-v9-2-2/10105 "2022-12-07T17:29:19Z")
I have the following code which calls AddArray() and it segfault. if (euclidean\_areas\_exist) { printf("xx00100\\n"); vtkNew\ vtk\_euclidean\_areas; vtk\_euclidean\_areas-\>SetName("eu\_areas"); vtk\_eucli… --- ## [PolyData face level attributes ?](https://discourse.vtk.org/t/polydata-face-level-attributes/10009)
**Author:** [@Nicholas\_Yue](https://discourse.vtk.org/u/Nicholas_Yue)\ **Replies:** 6\ **Last updated:** [December 7, 2022, 4:18pm UTC](https://discourse.vtk.org/t/polydata-face-level-attributes/10009 "2022-12-07T16:18:55Z")
I wish to produce a VTK polydata (eventually write it out as a \*.vtp file) where I can associate some scalar value (e.g. pH, temperature, salinity) on a per face level, how should I go about doing that ? Is there an exam… --- ## [How to wrap a custom made C++ VTK filter in Python?](https://discourse.vtk.org/t/how-to-wrap-a-custom-made-c-vtk-filter-in-python/10070)
**Author:** [@Edoardo\_Pasca](https://discourse.vtk.org/u/Edoardo_Pasca)\ **Replies:** 6\ **Last updated:** [December 7, 2022, 1:54pm UTC](https://discourse.vtk.org/t/how-to-wrap-a-custom-made-c-vtk-filter-in-python/10070 "2022-12-07T13:54:54Z")
Hi all, I created a VTK algorithm in Python using VTKPythonAlgorithmBase, which served me well. However, it doesn’t scale as it requires a few python for loops, which are infamously slow! I want to translate the code t… --- ## [extract material names from ObjImporter](https://discourse.vtk.org/t/extract-material-names-from-objimporter/10104)
**Author:** [@anirudh\_puligandla](https://discourse.vtk.org/u/anirudh_puligandla)\ **Replies:** 0\ **Last updated:** [December 7, 2022, 1:41pm UTC](https://discourse.vtk.org/t/extract-material-names-from-objimporter/10104 "2022-12-07T13:41:34Z")
Hi, I want to extract material names from an imported model using vtkOBJImporter. I am following the example at https://kitware.github.io/vtk-examples/site/Cxx/IO/OBJImporter/ . How can I get a list of material names (p… [Previous page](https://discourse.vtk.org/latest.md?page=105) [Next page](https://discourse.vtk.org/latest.md?page=107)