# Problem running Examples/GUI/Python/ImplicitPlaneWidget.py (vtkLODActor not found, etc)

**URL:** https://discourse.vtk.org/t/problem-running-examples-gui-python-implicitplanewidget-py-vtklodactor-not-found-etc/3045
**Category:** Support
**Created:** [April 14, 2020, 3:16am UTC](https://discourse.vtk.org/t/problem-running-examples-gui-python-implicitplanewidget-py-vtklodactor-not-found-etc/3045 "2020-04-14T03:16:59Z")
**Posts on this page:** 6
**Page:** 1

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### Author: ![Yasushi\_Saito](https://discourse.vtk.org/user_avatar/discourse.vtk.org/yasushi_saito/32/1634_2.png) [@Yasushi\_Saito](https://discourse.vtk.org/u/Yasushi_Saito)
#### Post date: [April 14, 2020, 3:16am UTC](https://discourse.vtk.org/t/problem-running-examples-gui-python-implicitplanewidget-py-vtklodactor-not-found-etc/3045/1 "2020-04-14T03:16:59Z")

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I’m trying to run VTK Examples/GUI/Python/ImplicitPlaneWidget.py and ran into a couple of issues.

- I downloaded & installed ParaView-5.8.0-MPI-Linux-Python3.7-64bit.tar.gz on Ubuntu 18.04.
- Then I ran pvpython ImplicitPlaneWidget.py, where pvpython is the binary that came with the above package.

I get:

AttributeError: module ‘vtkmodules.all’ has no attribute ‘vtkLODActor’

In fact I get this error on every script that uses vtkLODActor.  
So I replaced vtkLODActor to vtkActor, then I can see a window with a mace in a blue background, but I don’t see any implicit plane selection widget. I don’t see any error message otherwise.

Am I doing something wrong?

Thanks in advance,  
yaz

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### Author: ![ben.boeckel](https://discourse.vtk.org/letter_avatar_proxy/v4/letter/b/ea5d25/32.png) [@ben.boeckel](https://discourse.vtk.org/u/ben.boeckel)
#### Post date: [April 14, 2020, 12:57pm UTC](https://discourse.vtk.org/t/problem-running-examples-gui-python-implicitplanewidget-py-vtklodactor-not-found-etc/3045/2 "2020-04-14T12:57:43Z")

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I’m guessing that `vtkRenderingLOD` isn’t available. Can you `import vtkmodules.vtkRenderingLOD`?

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### Author: ![Yasushi\_Saito](https://discourse.vtk.org/user_avatar/discourse.vtk.org/yasushi_saito/32/1634_2.png) [@Yasushi\_Saito](https://discourse.vtk.org/u/Yasushi_Saito)
#### Post date: [April 14, 2020, 4:51pm UTC](https://discourse.vtk.org/t/problem-running-examples-gui-python-implicitplanewidget-py-vtklodactor-not-found-etc/3045/3 "2020-04-14T16:51:14Z")

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There’s no such module. I see the following vtkRender\* in vtkmodules:

vtkRenderingCore  
vtkRenderingContext2D  
vtkRenderingFreeType  
vtkRenderingOpenGL2  
vtkRenderingSceneGraph  
vtkRenderingVolume  
vtkRenderingRayTracing  
vtkRenderingVolumeOpenGL2  
vtkRenderingVolumeAMR  
vtkRenderingParallel  
vtkRenderingMatplotlib  
vtkRenderingLabel  
vtkRenderingLICOpenGL2  
vtkRenderingContextOpenGL2  
vtkRenderingGL2PSOpenGL2  
vtkRenderingAnnotation

I recompiled Paraview from scratch, and it seems like VTKRenderingLOD is not included in the build. I used the following cmake setting. I’m not all that familiar with cmake. Can someone enlighten me what’s going on?

cmake  
-GNinja  
-DPARAVIEW\_BUILD\_SHARED\_LIBS=ON  
-DBUILD\_TESTING=OFF  
-DPARAVIEW\_USE\_MPI=ON  
-DPARAVIEW\_USE\_PYTHON=ON  
-DPARAVIEW\_OPENGL\_HAS\_OSMESA=ON  
-DPARAVIEW\_OPENGL\_HAS\_EGL=OFF  
-DPARAVIEW\_USE\_QT=ON  
-DPARAVIEW\_ENABLE\_WEB=ON

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<div class="post-metadata">

### Author: ![ben.boeckel](https://discourse.vtk.org/letter_avatar_proxy/v4/letter/b/ea5d25/32.png) [@ben.boeckel](https://discourse.vtk.org/u/ben.boeckel)
#### Post date: [April 14, 2020, 5:17pm UTC](https://discourse.vtk.org/t/problem-running-examples-gui-python-implicitplanewidget-py-vtklodactor-not-found-etc/3045/4 "2020-04-14T17:17:38Z")

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You can pass `-DVTK_MODULE_ENABLE_VTK_RenderingLOD=YES` to force the module to build. @utkarshayachit Should the LOD module be tied to some ParaView build option?

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<div class="post-metadata">

### Author: ![Yasushi\_Saito](https://discourse.vtk.org/user_avatar/discourse.vtk.org/yasushi_saito/32/1634_2.png) [@Yasushi\_Saito](https://discourse.vtk.org/u/Yasushi_Saito)
#### Post date: [April 14, 2020, 5:18pm UTC](https://discourse.vtk.org/t/problem-running-examples-gui-python-implicitplanewidget-py-vtklodactor-not-found-etc/3045/5 "2020-04-14T17:18:46Z")

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As for vtkImplicitPlaneWidget, I missed that I needed to press “i” to activate the widget. Now I can see the widget.

So I guess at least for the examples, it’s safe to use vtkActor in place of vtkLODActor?

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<div class="post-metadata">

### Author: ![ben.boeckel](https://discourse.vtk.org/letter_avatar_proxy/v4/letter/b/ea5d25/32.png) [@ben.boeckel](https://discourse.vtk.org/u/ben.boeckel)
#### Post date: [April 14, 2020, 7:45pm UTC](https://discourse.vtk.org/t/problem-running-examples-gui-python-implicitplanewidget-py-vtklodactor-not-found-etc/3045/6 "2020-04-14T19:45:01Z")

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Ah, yeah probably. I don’t know what `vtkLODActor` gets you on top of it, but not requiring a subclass if the base is sufficient for examples is probably better.