# Hollow 2d markups in slice views

**URL:** https://discourse.slicer.org/t/hollow-2d-markups-in-slice-views/45754
**Category:** Support
**Tags:** python, markups-fiducials, markups
**Created:** [January 12, 2026, 4:40pm UTC](https://discourse.slicer.org/t/hollow-2d-markups-in-slice-views/45754 "2026-01-12T16:40:23Z")
**Posts on this page:** 3
**Page:** 1

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### Author: ![TomOssability](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/tomossability/32/81760_2.png) [@TomOssability](https://discourse.slicer.org/u/TomOssability)
#### Post date: [January 12, 2026, 4:40pm UTC](https://discourse.slicer.org/t/hollow-2d-markups-in-slice-views/45754/1 "2026-01-12T16:40:24Z")

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Hi, I understand support for 2D operations is limited due to this platform being mostly used for 3D tasks. However, I am developing a python extension that requires key point placement in single slice views, for which I would prefer the markup control point glyphs show as rings. I have a couple of questions:

- Has anyone had any success with showing markups in slice view without fill (circle2D, Square2D)
- If this is not possible, can anyone recommend an approach to developing a custom markup to serve this purpose?

Thanks,  
I would appreciate any help or similar experiences anyone can offer

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### Author: ![lassoan](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/lassoan/32/13_2.png) [@lassoan](https://discourse.slicer.org/u/lassoan)
#### Post date: [January 12, 2026, 4:50pm UTC](https://discourse.slicer.org/t/hollow-2d-markups-in-slice-views/45754/2 "2026-01-12T16:50:53Z")

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Currently, control point glyph filling is not controllable independently because filling it is used as a hint when fiducial projection is enabled (filling indicates if the point is in front of or behind the current slice).

 ![image](https://us1.discourse-cdn.com/flex002/uploads/slicer/original/3X/6/a/6afb9d0800529ac6a1db9a183452c5bd51fee31b.jpeg)

You can use Cross2D, StarBurst2D, CrossDot2D glyphs that do not occlude the center.

 ![image](https://us1.discourse-cdn.com/flex002/uploads/slicer/original/3X/4/0/407a74bca54412a81477a01df311d9a89d0826a8.jpeg)

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<div class="post-metadata">

### Author: ![TomOssability](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/tomossability/32/81760_2.png) [@TomOssability](https://discourse.slicer.org/u/TomOssability)
#### Post date: [January 13, 2026, 12:28am UTC](https://discourse.slicer.org/t/hollow-2d-markups-in-slice-views/45754/3 "2026-01-13T00:28:56Z")

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Thanks for your quick reply. I have added a switcher in my module to toggle between CrossDot2D and “circle” glyphs, which I am showing by programatically shifting the control points behind the slice view and showing their projections in slice view with ‘outline behind slice pane’ enabled (Using the Circle2D glyph type).

 ![image](https://us1.discourse-cdn.com/flex002/uploads/slicer/original/3X/a/a/aaa72e6edddac059b6dea59ff336cb6583d67c71.jpeg)

 ![image](https://us1.discourse-cdn.com/flex002/uploads/slicer/original/3X/9/0/902b6ac5a78efdc0258bc27f6fd5b288b9f0adfc.jpeg)

While this brings a new challenge when moving to 3d space and forces a fill on the circles while dragging them, it is sufficient for my requirement.

Thanks for your assistance and eager support for those using your software 🙂  
Cheers.