# Can't enter selection mode in a rendered window
**URL:** https://discourse.vtk.org/t/cant-enter-selection-mode-in-a-rendered-window/3975
**Category:** Support
**Created:** [August 13, 2020, 10:16pm UTC](https://discourse.vtk.org/t/cant-enter-selection-mode-in-a-rendered-window/3975 "2020-08-13T22:16:23Z")
**Posts on this page:** 10
**Page:** 1
### Author:  [@beginner](https://discourse.vtk.org/u/beginner)
#### Post date: [August 13, 2020, 10:16pm UTC](https://discourse.vtk.org/t/cant-enter-selection-mode-in-a-rendered-window/3975/1 "2020-08-13T22:16:23Z")
Hi everyone!
I’m having trouble entering the selection mode in a render window. Do I just click on ‘r’ on my keyboard? I’ve tried that but it doesn’t work. I’m not sure why that is…
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### Author:  [@Paulo\_Carvalho](https://discourse.vtk.org/u/Paulo_Carvalho)
#### Post date: [August 14, 2020, 12:02pm UTC](https://discourse.vtk.org/t/cant-enter-selection-mode-in-a-rendered-window/3975/2 "2020-08-14T12:02:49Z")
Hello, friend!
Key ‘p’ works for me. A bounding box appears around the actor under the mouse pointer. Is it that you want?
regards,
Paulo
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### Author:  [@beginner](https://discourse.vtk.org/u/beginner)
#### Post date: [August 15, 2020, 1:39am UTC](https://discourse.vtk.org/t/cant-enter-selection-mode-in-a-rendered-window/3975/3 "2020-08-15T01:39:20Z")
Thanks. I’m trying to enable the selection mode to select points points I’ve added to a polyData. Sometimes it enters the selection mode just fine by clicking ‘r’ but it’s not consistent.
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### Author:  [@Paulo\_Carvalho](https://discourse.vtk.org/u/Paulo_Carvalho)
#### Post date: [August 15, 2020, 2:53pm UTC](https://discourse.vtk.org/t/cant-enter-selection-mode-in-a-rendered-window/3975/4 "2020-08-15T14:53:40Z")
Can you elaborate more? I mean: what is the expected behavior? What are you getting?
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### Author:  [@beginner](https://discourse.vtk.org/u/beginner)
#### Post date: [August 31, 2020, 4:49pm UTC](https://discourse.vtk.org/t/cant-enter-selection-mode-in-a-rendered-window/3975/5 "2020-08-31T16:49:38Z")
When I press r, it doesn’t allow me to enter selection mode and only does so sporadically. I’m not sure if the mode I’ve started with is incorrect or what might of caused it.
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### Author:  [@Paulo\_Carvalho](https://discourse.vtk.org/u/Paulo_Carvalho)
#### Post date: [September 1, 2020, 2:06pm UTC](https://discourse.vtk.org/t/cant-enter-selection-mode-in-a-rendered-window/3975/6 "2020-09-01T14:06:44Z")
Hi, friend,
If I’m not mistaken, here are the default key bindings:
- **Keypress 3:** toggle the render window into and out of stereo mode (requires red/blue or polarized glasses, depending on your device).
- **Keypress e:** exit the application.
- **Keypress f:** fly to the picked point
- **Keypress p:** perform a pick operation.
- **Keypress r: reset the camera view along the current view direction. Centers the actors and moves the camera so that all actors are visible.**
- **Keypress s:** modify the representation of all actors so that they are surfaces.
- **Keypress u:** invoke the user-defined function. Typically, this keypress will bring up an interactor that you can type commands in.
- **Keypress w:** modify the representation of all actors so that they are wireframes.
To select actors, you need to implement a picking callback.
regards,
Paulo
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### Author:  [@beginner](https://discourse.vtk.org/u/beginner)
#### Post date: [September 2, 2020, 9:34pm UTC](https://discourse.vtk.org/t/cant-enter-selection-mode-in-a-rendered-window/3975/7 "2020-09-02T21:34:05Z")
I’m using vtkPolygonalSurfacePointPlacer and I’d like to select the points “picked.” Do I still need to implement a picking callback?
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### Author:  [@Paulo\_Carvalho](https://discourse.vtk.org/u/Paulo_Carvalho)
#### Post date: [September 2, 2020, 9:37pm UTC](https://discourse.vtk.org/t/cant-enter-selection-mode-in-a-rendered-window/3975/8 "2020-09-02T21:37:49Z")
From the docs [VTK: vtkPolygonalSurfacePointPlacer Class Reference](https://vtk.org/doc/nightly/html/classvtkPolygonalSurfacePointPlacer.html) :
> Place points on the surface of polygonal data.
>
> [vtkPolygonalSurfacePointPlacer](https://vtk.org/doc/nightly/html/classvtkPolygonalSurfacePointPlacer.html) places points on polygonal data and is meant to be used in conjunction with [vtkPolygonalSurfaceContourLineInterpolator](https://vtk.org/doc/nightly/html/classvtkPolygonalSurfaceContourLineInterpolator.html).
To me it doesn’t seem to select actors…
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### Author:  [@beginner](https://discourse.vtk.org/u/beginner)
#### Post date: [September 2, 2020, 9:42pm UTC](https://discourse.vtk.org/t/cant-enter-selection-mode-in-a-rendered-window/3975/9 "2020-09-02T21:42:42Z")
I see. I’m trying to drag the points placed such that it would generate new lines(I’m using vtkPolygonalSurfaceContourLineInterpolator) connecting the points.
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### Author:  [@Paulo\_Carvalho](https://discourse.vtk.org/u/Paulo_Carvalho)
#### Post date: [September 2, 2020, 9:52pm UTC](https://discourse.vtk.org/t/cant-enter-selection-mode-in-a-rendered-window/3975/10 "2020-09-02T21:52:12Z")
If you want to drag actors with the mouse you can try this: [https://vtk.org/Wiki/VTK/Examples/Cxx/Visualization/MoveActor](https://vtk.org/Wiki/VTK/Examples/Cxx/Visualization/MoveActor) .