# Cannot pick vtkActor inside vtkOrientationMarkerWidget.

**URL:** https://discourse.vtk.org/t/cannot-pick-vtkactor-inside-vtkorientationmarkerwidget/14386
**Category:** Development
**Created:** [August 10, 2024, 3:01pm UTC](https://discourse.vtk.org/t/cannot-pick-vtkactor-inside-vtkorientationmarkerwidget/14386 "2024-08-10T15:01:16Z")
**Posts on this page:** 3
**Page:** 1

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### Author: ![tomdong](https://discourse.vtk.org/user_avatar/discourse.vtk.org/tomdong/32/9167_2.png) [@tomdong](https://discourse.vtk.org/u/tomdong)
#### Post date: [August 10, 2024, 3:01pm UTC](https://discourse.vtk.org/t/cannot-pick-vtkactor-inside-vtkorientationmarkerwidget/14386/1 "2024-08-10T15:01:16Z")

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Hi friends,  
I’m using vtk9.3 to build a 3D render app. I want to create a ‘viewcube’ with vtkOrientationMarkerWidget, here is what I’ve done:

1. create 6 face actors;
2. create a vtkAssembly and add face actors as parts;
3. set the vtkAssembly to vtkOrientationMarkerWidget as marker;  
now, I have the vtkOrientationMarkerWidget in render window, but I cannot pick any assembly/actor of the vtkOrientationMarkerWidget.  
I got a lot of sample code from google & AI, but none of them works.

Any suggestion to pick vtkActor inside vtkOrientationMarkerWidget? or there is no way to achieve this?

Thanks everyone!

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### Author: ![jaswantp](https://discourse.vtk.org/user_avatar/discourse.vtk.org/jaswantp/32/10046_2.png) [@jaswantp](https://discourse.vtk.org/u/jaswantp)
#### Post date: [August 10, 2024, 4:15pm UTC](https://discourse.vtk.org/t/cannot-pick-vtkactor-inside-vtkorientationmarkerwidget/14386/2 "2024-08-10T16:15:07Z")

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Hello @tomdong

Can you explain what you intend to do upon picking one of those 6 face actors. The assembly is definitely picked by default, but that widget doesn’t implement a whole lot besides letting you drag the widget around. Do you want to re-orient the camera to view down that axis?

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### Author: ![tomdong](https://discourse.vtk.org/user_avatar/discourse.vtk.org/tomdong/32/9167_2.png) [@tomdong](https://discourse.vtk.org/u/tomdong)
#### Post date: [August 10, 2024, 5:08pm UTC](https://discourse.vtk.org/t/cannot-pick-vtkactor-inside-vtkorientationmarkerwidget/14386/3 "2024-08-10T17:08:14Z")

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Thanks for your reply @jaswantp , I just found the reason to my question:  
the orientation-marker-widget is rendered by another render, it’s not the same as default 3d model render, once I pass the correct renderer to pick function, I can pick the vtkAssembly/path inside the vtkOrientationMarkerWidget using mouse.

Thanks again 🙂