# Support

**URL:** https://discourse.vtk.org/c/support/6.md?page=66

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

**Page:** 67

---

## [Rendering VTK in external OpenGL context with single buffering](https://discourse.vtk.org/t/rendering-vtk-in-external-opengl-context-with-single-buffering/5863)

<div class="topic-metadata">

**Author:** [@Carol\_Capek](https://discourse.vtk.org/u/Carol_Capek)\
**Replies:** 7\
**Last updated:** [October 11, 2022, 7:43am UTC](https://discourse.vtk.org/t/rendering-vtk-in-external-opengl-context-with-single-buffering/5863 "2022-10-11T07:43:11Z")

</div>

Hi All! I want to render a circle (to start off slow) using VTK in an existing application. We use GLFW to create a window and the OpenGL context as well as GLAD for the bindings. I presume that vtkExternalOpenGLRenderW…

---

## [Render fuction cost too much time on repaint](https://discourse.vtk.org/t/render-fuction-cost-too-much-time-on-repaint/9562)

<div class="topic-metadata">

**Author:** [@herman](https://discourse.vtk.org/u/herman)\
**Replies:** 2\
**Last updated:** [October 11, 2022, 3:20am UTC](https://discourse.vtk.org/t/render-fuction-cost-too-much-time-on-repaint/9562 "2022-10-11T03:20:43Z")

</div>

Hello I received 15 million points,use vtk & c# to show them. when i use renderWindow to call fuction “render” (render window and render is already global vars),it costs 1.3s(have not interact yet). The repaint time i…

---

## [error when installing VTK with VS 2019](https://discourse.vtk.org/t/error-when-installing-vtk-with-vs-2019/9561)

<div class="topic-metadata">

**Author:** [@vromero59](https://discourse.vtk.org/u/vromero59)\
**Replies:** 1\
**Last updated:** [October 11, 2022, 2:57am UTC](https://discourse.vtk.org/t/error-when-installing-vtk-with-vs-2019/9561 "2022-10-11T02:57:31Z")

</div>

I am using Visual Studio 2019 to compile VTK. When I compile INSTALL, I got the messake MSB3073. How I can correct this error? The complete message is as follows: 266\>C:\\Program Files (x86)\\Microsoft Visual Studio\\201…

---

## [View vtkOpenGLShaderCache substitutions and compile error message](https://discourse.vtk.org/t/view-vtkopenglshadercache-substitutions-and-compile-error-message/7040)

<div class="topic-metadata">

**Author:** [@nickc](https://discourse.vtk.org/u/nickc)\
**Replies:** 6\
**Last updated:** [October 11, 2022, 2:53am UTC](https://discourse.vtk.org/t/view-vtkopenglshadercache-substitutions-and-compile-error-message/7040 "2022-10-11T02:53:17Z")

</div>

Hi all, I’m going a bit crazy trying to figure out a compilation issue on MacOS. I know OpenGL isn’t supported anymore… but most of our code has been working great except for this one shader that I am trying to debug. U…

---

## [Backface Culling with PBR](https://discourse.vtk.org/t/backface-culling-with-pbr/9547)

<div class="topic-metadata">

**Author:** [@akaszynski](https://discourse.vtk.org/u/akaszynski)\
**Replies:** 5\
**Last updated:** [October 10, 2022, 9:29pm UTC](https://discourse.vtk.org/t/backface-culling-with-pbr/9547 "2022-10-10T21:29:15Z")

</div>

Hello, Is there a way to disable backface culling with physically based rendering? It seems that whenever PBR is enabled within VTK, backfaces are culled regardless of the setting of SetBackfaceCulling. Thanks!

---

## [Question about resample with dataset filter](https://discourse.vtk.org/t/question-about-resample-with-dataset-filter/9552)

<div class="topic-metadata">

**Author:** [@1116](https://discourse.vtk.org/u/1116)\
**Replies:** 0\
**Last updated:** [October 9, 2022, 4:45pm UTC](https://discourse.vtk.org/t/question-about-resample-with-dataset-filter/9552 "2022-10-09T16:45:17Z")

</div>

Hello, guys, could I ask a question regarding the resample with data set filter? I read the associated blog here https://www.kitware.com/dataset-resampling-filters/ I’m wondering if it is possible to resample data betw…

---

## [How to make a point cloud data from DICOM Series?](https://discourse.vtk.org/t/how-to-make-a-point-cloud-data-from-dicom-series/9505)

<div class="topic-metadata">

**Author:** [@Kim\_William](https://discourse.vtk.org/u/Kim_William)\
**Replies:** 5\
**Last updated:** [October 9, 2022, 8:51am UTC](https://discourse.vtk.org/t/how-to-make-a-point-cloud-data-from-dicom-series/9505 "2022-10-09T08:51:47Z")

</div>

Hi all. I’m using the 3D Slicer program. As far as I know, this program was based on the VTK library. The below image is a screenshot of the 3D Slicer program UI. I used DICOM images from the VTK ReadDICOMSeries ex…

---

## [Adding shader program to VTK OpenGL pipeline](https://discourse.vtk.org/t/adding-shader-program-to-vtk-opengl-pipeline/7348)

<div class="topic-metadata">

**Author:** [@Josef\_Biberstein](https://discourse.vtk.org/u/Josef_Biberstein)\
**Replies:** 2\
**Last updated:** [October 9, 2022, 3:10am UTC](https://discourse.vtk.org/t/adding-shader-program-to-vtk-opengl-pipeline/7348 "2022-10-09T03:10:38Z")

</div>

I’m trying to use an OpenGL shader I have that renders an infinite regular grid for use as a reference in the visualization of a vehicle trajectory. I’ve confirmed it works in base OpenGL, but I’m a bit confused on how I…

---

## [Convert numpy landmarks point coordinates to VTK.Polydata, and align them using the vtkProcrustesAlignmentFilter ()](https://discourse.vtk.org/t/convert-numpy-landmarks-point-coordinates-to-vtk-polydata-and-align-them-using-the-vtkprocrustesalignmentfilter/9543)

<div class="topic-metadata">

**Author:** [@joy](https://discourse.vtk.org/u/joy)\
**Replies:** 0\
**Last updated:** [October 7, 2022, 8:12am UTC](https://discourse.vtk.org/t/convert-numpy-landmarks-point-coordinates-to-vtk-polydata-and-align-them-using-the-vtkprocrustesalignmentfilter/9543 "2022-10-07T08:12:29Z")

</div>

Hello VTK Team, I am new to VTK, I want to use the vtkProcrustesAlignmentFilter () for aligning multiple landmark points. I use these codes to do it? import numpy as np import open3d as o3d import pyvista as pv impor…

---

## [Determine point inside/outside enclosed surface](https://discourse.vtk.org/t/determine-point-inside-outside-enclosed-surface/9539)

<div class="topic-metadata">

**Author:** [@drpeterfranz](https://discourse.vtk.org/u/drpeterfranz)\
**Replies:** 9\
**Last updated:** [October 7, 2022, 2:13am UTC](https://discourse.vtk.org/t/determine-point-inside-outside-enclosed-surface/9539 "2022-10-07T02:13:03Z")

</div>

Hi there, I have a problem here we my application receives a triangulated, closed surface which encloses a volume. The resolution of this surface is high, i.e. there are \> 100,000 triangles in it, and it can be concave.…

---

## [Reading and rendering a digital elevation model (DEM) in VTK](https://discourse.vtk.org/t/reading-and-rendering-a-digital-elevation-model-dem-in-vtk/9536)

<div class="topic-metadata">

**Author:** [@llobera](https://discourse.vtk.org/u/llobera)\
**Replies:** 0\
**Last updated:** [October 6, 2022, 11:05am UTC](https://discourse.vtk.org/t/reading-and-rendering-a-digital-elevation-model-dem-in-vtk/9536 "2022-10-06T11:05:16Z")

</div>

I have a few questions regarding how to best generate a 3D rendering of digital elevation model (DEM). Is there a way to access via python bindings the GDALRasterReader() function? This functionality appears in VTK but…

---

## [Possible bug in vtkStringArray](https://discourse.vtk.org/t/possible-bug-in-vtkstringarray/9528)

<div class="topic-metadata">

**Author:** [@MarKara](https://discourse.vtk.org/u/MarKara)\
**Replies:** 3\
**Last updated:** [October 6, 2022, 6:02am UTC](https://discourse.vtk.org/t/possible-bug-in-vtkstringarray/9528 "2022-10-06T06:02:34Z")

</div>

Hi I recently moved from Activiz 6.3 to 9.3 and discovered possible bug in compiled vtkStringArray. Here is the test vtkStringArray stringArray = new vtkStringArray(); stringArray.SetNumberOfValues(3); stringArray.…

---

## [VTK-PROJ simple example not working](https://discourse.vtk.org/t/vtk-proj-simple-example-not-working/9532)

<div class="topic-metadata">

**Author:** [@Tomasso](https://discourse.vtk.org/u/Tomasso)\
**Replies:** 6\
**Last updated:** [October 6, 2022, 1:12am UTC](https://discourse.vtk.org/t/vtk-proj-simple-example-not-working/9532 "2022-10-06T01:12:03Z")

</div>

VTK source comes with self-contained PROJ source, in directory ThirdParty/libproj, and library libvtklibproj.so is built from that. Compiling application C++ code with this flag enables VTK PROJ headers and the aforemen…

---

## [Selecting random points of a PolyData (Stratified sampling)](https://discourse.vtk.org/t/selecting-random-points-of-a-polydata-stratified-sampling/7003)

<div class="topic-metadata">

**Author:** [@mau\_igna\_06](https://discourse.vtk.org/u/mau_igna_06)\
**Replies:** 33\
**Last updated:** [October 5, 2022, 6:11pm UTC](https://discourse.vtk.org/t/selecting-random-points-of-a-polydata-stratified-sampling/7003 "2022-10-05T18:11:06Z")

</div>

Hi. I would like to know how to get a sample of points of my polydata that are evenly distributed on the mesh surface. My input is a longBonePolyData. Here is my code till now: desiredNumberOfPoints = 1000 ratio = int(…

---

## [How to actually to convert 3d numpy array of DICOM images into vtkImageData and vtkAlgorithmOutput?](https://discourse.vtk.org/t/how-to-actually-to-convert-3d-numpy-array-of-dicom-images-into-vtkimagedata-and-vtkalgorithmoutput/9529)

<div class="topic-metadata">

**Author:** [@BJladika](https://discourse.vtk.org/u/BJladika)\
**Replies:** 2\
**Last updated:** [October 5, 2022, 2:23pm UTC](https://discourse.vtk.org/t/how-to-actually-to-convert-3d-numpy-array-of-dicom-images-into-vtkimagedata-and-vtkalgorithmoutput/9529 "2022-10-05T14:23:06Z")

</div>

As I’ve previously in other topic mentioned, I have a vtkResliceCursor, which uses vtkImageData and vtkAlgorithmOutput. Both were provided by vtkDICOMImageReader but it had few flaws. So I’ve decided to generate a 3d num…

---

## [Possible inconsistency in vtknetcdf?](https://discourse.vtk.org/t/possible-inconsistency-in-vtknetcdf/9514)

<div class="topic-metadata">

**Author:** [@waebbl](https://discourse.vtk.org/u/waebbl)\
**Replies:** 4\
**Last updated:** [October 4, 2022, 4:23pm UTC](https://discourse.vtk.org/t/possible-inconsistency-in-vtknetcdf/9514 "2022-10-04T16:23:21Z")

</div>

The VERSION variable in ThirdParty/netcdf/vtknetcdf/CMakeLists.txt is being set to be 4.8.1. However the PACKAGE\_VERSION is defined to be “4.5.0”\[1\]. Is this correct? \[1\] https://gitlab.kitware.com/vtk/vtk/-/blob/master…

---

## [Obtaining multiple z-buffers after rotating camera](https://discourse.vtk.org/t/obtaining-multiple-z-buffers-after-rotating-camera/9503)

<div class="topic-metadata">

**Author:** [@llobera](https://discourse.vtk.org/u/llobera)\
**Replies:** 1\
**Last updated:** [October 3, 2022, 7:09pm UTC](https://discourse.vtk.org/t/obtaining-multiple-z-buffers-after-rotating-camera/9503 "2022-10-03T19:09:21Z")

</div>

I would like to be able to capture the z-buffer for different planes around my camera position. Once centered on one direction I would like to make a call back what rotate the camera by a certain number of degrees and du…

---

## [vtkDICOMImageReader function SetFileNames is not working?](https://discourse.vtk.org/t/vtkdicomimagereader-function-setfilenames-is-not-working/9521)

<div class="topic-metadata">

**Author:** [@BJladika](https://discourse.vtk.org/u/BJladika)\
**Replies:** 1\
**Last updated:** [October 3, 2022, 3:44pm UTC](https://discourse.vtk.org/t/vtkdicomimagereader-function-setfilenames-is-not-working/9521 "2022-10-03T15:44:45Z")

</div>

So I have stumbled on example of vtkResliceCursor which uses a vtkDICOMImageReader function SetDirectoryName for generating output. And I have a set of DICOM Files. reader = vtkDICOMImageReader(); reader.SetDirectoryNam…

---

## [vtkRectf and vtkRectd not available in Java wrapper](https://discourse.vtk.org/t/vtkrectf-and-vtkrectd-not-available-in-java-wrapper/9486)

<div class="topic-metadata">

**Author:** [@Martin3d](https://discourse.vtk.org/u/Martin3d)\
**Replies:** 3\
**Last updated:** [September 29, 2022, 1:04pm UTC](https://discourse.vtk.org/t/vtkrectf-and-vtkrectd-not-available-in-java-wrapper/9486 "2022-09-29T13:04:03Z")

</div>

Hi, As the title said, I can’t find vtkRectf neither vtkRectd in the Java generated wrapper… although I get a java file generated for vtkRect. However the generated java class is not public hence can not be imported. L…

---

## [Polygon edges are not rendering properly](https://discourse.vtk.org/t/polygon-edges-are-not-rendering-properly/9494)

<div class="topic-metadata">

**Author:** [@manoj.lad](https://discourse.vtk.org/u/manoj.lad)\
**Replies:** 0\
**Last updated:** [September 29, 2022, 7:42am UTC](https://discourse.vtk.org/t/polygon-edges-are-not-rendering-properly/9494 "2022-09-29T07:42:24Z")

</div>

Hello, We have recently switched from VTK 7.0.0 to VTK 9.2.0. We have to show meshed face. For that we have used following code. We are using QT 6.3.2 for our application. vtkPolyData\* polyData = vtkPolyData::New…

---

## [Failed to inherit vtkRenderer](https://discourse.vtk.org/t/failed-to-inherit-vtkrenderer/9481)

<div class="topic-metadata">

**Author:** [@zhang-qiang-github](https://discourse.vtk.org/u/zhang-qiang-github)\
**Replies:** 2\
**Last updated:** [September 29, 2022, 7:22am UTC](https://discourse.vtk.org/t/failed-to-inherit-vtkrenderer/9481 "2022-09-29T07:22:09Z")

</div>

I want to write a class which inherit from vtkRenderer. My code is: #include \<vtkAutoInit.h\> VTK\_MODULE\_INIT(vtkRenderingOpenGL2); VTK\_MODULE\_INIT(vtkInteractionStyle); VTK\_MODULE\_INIT(vtkRenderingVolumeOpenGL2); VTK\_M…

---

## [Bool operation between concave poly and cube](https://discourse.vtk.org/t/bool-operation-between-concave-poly-and-cube/9489)

<div class="topic-metadata">

**Author:** [@lele.wang](https://discourse.vtk.org/u/lele.wang)\
**Replies:** 0\
**Last updated:** [September 29, 2022, 3:41am UTC](https://discourse.vtk.org/t/bool-operation-between-concave-poly-and-cube/9489 "2022-09-29T03:41:44Z")

</div>

Hi all, I tried to use a concave body and a cube for Boolean calculation and difference. Before calculation, I used vtkTriangleFilter to triangulate them respectively. The calculated results are not what I want。 Any…

---

## [Possible timeout in parseAsArrayBuffer](https://discourse.vtk.org/t/possible-timeout-in-parseasarraybuffer/9470)

<div class="topic-metadata">

**Author:** [@riddlexter](https://discourse.vtk.org/u/riddlexter)\
**Replies:** 4\
**Last updated:** [September 28, 2022, 7:51pm UTC](https://discourse.vtk.org/t/possible-timeout-in-parseasarraybuffer/9470 "2022-09-28T19:51:10Z")

</div>

Is there a timeout in parseAsArrayBuffer from ITKImageReader? Because when I try to get data from a slow server it gives error in Promise, but if I get the same file from a local server it works well, no problems, both u…

---

## [Read image data from RAM](https://discourse.vtk.org/t/read-image-data-from-ram/9412)

<div class="topic-metadata">

**Author:** [@masoud](https://discourse.vtk.org/u/masoud)\
**Replies:** 3\
**Last updated:** [September 28, 2022, 6:11pm UTC](https://discourse.vtk.org/t/read-image-data-from-ram/9412 "2022-09-28T18:11:53Z")

</div>

Dear all, I was willing to build a Dicom image viewer using vtk (more specifically Activiz) and could build it successfully. vtkDicomImageReader can read standard Dicom format but cannot read other formats. This means t…

---

## [vtk how to prevent the blur edge?](https://discourse.vtk.org/t/vtk-how-to-prevent-the-blur-edge/9484)

<div class="topic-metadata">

**Author:** [@zhang-qiang-github](https://discourse.vtk.org/u/zhang-qiang-github)\
**Replies:** 0\
**Last updated:** [September 28, 2022, 9:52am UTC](https://discourse.vtk.org/t/vtk-how-to-prevent-the-blur-edge/9484 "2022-09-28T09:52:25Z")

</div>

I want to display a color image and a gray image. The code is about (python): grayActor = ... colorActor = ... render.AddActor(grayActor) render.AddActor(colorActor ) And the result is shown as the above picture. …

---

## [Pick LPS coordinate from 3d model](https://discourse.vtk.org/t/pick-lps-coordinate-from-3d-model/9475)

<div class="topic-metadata">

**Author:** [@dj\_96](https://discourse.vtk.org/u/dj_96)\
**Replies:** 0\
**Last updated:** [September 27, 2022, 7:05pm UTC](https://discourse.vtk.org/t/pick-lps-coordinate-from-3d-model/9475 "2022-09-27T19:05:15Z")

</div>

I’ve loaded up an STL file that should be in LPS coordinates. I’m able to place spheres on the 3d mesh with: picker = vtk.vtkCellPicker() picker.Pick(x, y, 0, renderer) p = picker.getPickPosition() Then p is the corre…

---

## [Non-rigid mesh registration of lung contour meshes](https://discourse.vtk.org/t/non-rigid-mesh-registration-of-lung-contour-meshes/9472)

<div class="topic-metadata">

**Author:** [@qod\_rec](https://discourse.vtk.org/u/qod_rec)\
**Replies:** 1\
**Last updated:** [September 27, 2022, 4:50pm UTC](https://discourse.vtk.org/t/non-rigid-mesh-registration-of-lung-contour-meshes/9472 "2022-09-27T16:50:39Z")

</div>

Hello! I have some chest CTs with lung contours labeled. I have generated the contour meshes in 3D slicer and these meshes are in STL format. I use a mesh simplification algorithm in meshlab to simplify one mesh from t…

---

## [Multi 3D textures for OpenGL Mapper](https://discourse.vtk.org/t/multi-3d-textures-for-opengl-mapper/9108)

<div class="topic-metadata">

**Author:** [@Ruooo](https://discourse.vtk.org/u/Ruooo)\
**Replies:** 2\
**Last updated:** [September 27, 2022, 1:21pm UTC](https://discourse.vtk.org/t/multi-3d-textures-for-opengl-mapper/9108 "2022-09-27T13:21:42Z")

</div>

Hello, we created a customized vtkOpenGLPolyDataMapper class and already have one 3D vtkTextureObject with four components(RGBA). For our new feature, we need to use more 3D textures at the same time. From the documentat…

---

## [vtkMultiBlockDataSet can not show vtkUnstructuredGrid data?](https://discourse.vtk.org/t/vtkmultiblockdataset-can-not-show-vtkunstructuredgrid-data/9456)

<div class="topic-metadata">

**Author:** [@rockydut](https://discourse.vtk.org/u/rockydut)\
**Replies:** 3\
**Last updated:** [September 26, 2022, 11:57pm UTC](https://discourse.vtk.org/t/vtkmultiblockdataset-can-not-show-vtkunstructuredgrid-data/9456 "2022-09-26T23:57:55Z")

</div>

When I input a vtkUnstructuredGrid data into vtkMultiBlockDataSet, it can not show the data. Does the vtkMultiBlockDataSet only can show vtkPolyData? vtkNew\<vtkMultiBlockDataSet\> root; vtkNew\<vtkSphereSource\> block1; …

---

## [Multi geometry interaction](https://discourse.vtk.org/t/multi-geometry-interaction/9276)

<div class="topic-metadata">

**Author:** [@rockydut](https://discourse.vtk.org/u/rockydut)\
**Replies:** 10\
**Last updated:** [September 26, 2022, 10:04am UTC](https://discourse.vtk.org/t/multi-geometry-interaction/9276 "2022-09-26T10:04:20Z")

</div>

I have multiple geometries, each of which is stored in vtkunstructuredGrid/vtkPolyData. I hope that when the mouse clicks on a geometry during interaction, the geometry can be selected. Of course, I also want to be able…

[Previous page](https://discourse.vtk.org/c/support/6.md?page=65)

[Next page](https://discourse.vtk.org/c/support/6.md?page=67)