# centering (justification/alignment) of vtkFollower text

**URL:** https://discourse.vtk.org/t/centering-justification-alignment-of-vtkfollower-text/1632
**Category:** Support
**Created:** [August 21, 2019, 3:02pm UTC](https://discourse.vtk.org/t/centering-justification-alignment-of-vtkfollower-text/1632 "2019-08-21T15:02:07Z")
**Posts on this page:** 1
**Showing post:** 3

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### Author: ![dmgroppe](https://discourse.vtk.org/user_avatar/discourse.vtk.org/dmgroppe/32/25_2.png) [@dmgroppe](https://discourse.vtk.org/u/dmgroppe)
#### Post date: [August 27, 2019, 7:52pm UTC](https://discourse.vtk.org/t/centering-justification-alignment-of-vtkfollower-text/1632/3 "2019-08-27T19:52:04Z")

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Thanks very much, Alison! However, it appears that vtkBillboardTextActor3D has some issues with occlusion when using it with raycasting:

> [@vtkBillboardTextActor3D text always renders behind raycast volume](https://discourse.vtk.org/t/vtkbillboardtextactor3d-text-always-renders-behind-raycast-volume/983/2):
>
> Displaying labels correctly is extremely difficult. I’ve spent a lot of time experimenting with different options for markup display in 3D Slicer, but each option has different limitations. To tackle occlusion: To make sure the labels are not occluded, you can display 3D label actors on a separate layer or use 2D actors. However, then you need to manually hide the actors when the corresponding point of interest is occluded. In general, determining if a certain point is occluded is a very costly…

@lassoan, I like your suggestion of using vtkLabelPlacementMapper, but I can’t figure out how to control the size of the text or its alignment/justification.

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_[View the full topic](https://discourse.vtk.org/t/centering-justification-alignment-of-vtkfollower-text/1632)._