# add label to clicked 3D position

**URL:** https://discourse.vtk.org/t/add-label-to-clicked-3d-position/3828
**Category:** Support
**Created:** [July 22, 2020, 3:55pm UTC](https://discourse.vtk.org/t/add-label-to-clicked-3d-position/3828 "2020-07-22T15:55:49Z")
**Posts on this page:** 2
**Page:** 1

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### Author: ![mohammad\_jalili](https://discourse.vtk.org/user_avatar/discourse.vtk.org/mohammad_jalili/32/2120_2.png) [@mohammad\_jalili](https://discourse.vtk.org/u/mohammad_jalili)
#### Post date: [July 22, 2020, 3:55pm UTC](https://discourse.vtk.org/t/add-label-to-clicked-3d-position/3828/1 "2020-07-22T15:55:49Z")

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Hello everyone.  
I have rendered a 3D DICOM and now I want to add vtkTextActor3D in some 3D position when user clicks. How to do that?

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### Author: ![xxyyy159](https://discourse.vtk.org/user_avatar/discourse.vtk.org/xxyyy159/32/4528_2.png) [@xxyyy159](https://discourse.vtk.org/u/xxyyy159)
#### Post date: [May 4, 2021, 1:37pm UTC](https://discourse.vtk.org/t/add-label-to-clicked-3d-position/3828/2 "2021-05-04T13:37:33Z")

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Hi,  
My solution is that:  
1/ add an observer to get the position of you clicked mouse  
2/ set the 3DActor to that position.  
Here are some examples available:  
[https://kitware.github.io/vtk-examples/site/Cxx/Interaction/MouseEventsObserver/](https://kitware.github.io/vtk-examples/site/Cxx/Interaction/MouseEventsObserver/)