# IDAVLM Converter Not Aligning Landmarks to Model

**URL:** <https://discourse.slicer.org/t/idavlm-converter-not-aligning-landmarks-to-model/46940>\
**Category:** Support\
**Tags:** slicermorph, idavlm\
**Created:** [May 6, 2026, 3:28pm UTC](https://discourse.slicer.org/t/idavlm-converter-not-aligning-landmarks-to-model/46940 "2026-05-06T15:28:24Z")\
**Posts on this page:** 6\
**Page:** 1

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**Author:** ![ThomasVanParys](https://avatars.discourse-cdn.com/v4/letter/t/7ea924/32.png) [@ThomasVanParys](https://discourse.slicer.org/u/ThomasVanParys)\
**Post date:** [May 6, 2026, 3:28pm UTC](https://discourse.slicer.org/t/idavlm-converter-not-aligning-landmarks-to-model/46940/1 "2026-05-06T15:28:24Z")

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Hello All,

I have create a patch in Landmark IDAV, converting the .PTS in SlicerMorph IDAVLM converter. However, they do not align with the corresponding mesh used in Landmark as seen in the UI:

 ![Screenshot 2026-05-06 162357](https://us1.discourse-cdn.com/flex002/uploads/slicer/original/3X/6/0/60eb67ea9d63cd73a4a669aa9b8292ece3ba31cb.jpeg)

I am clearly missing a stage, but cannot work it out (both mesh and landmarks need a common coordinate system clearly…).

Thanks for the help

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**Author:** ![muratmaga](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/muratmaga/32/3622_2.png) [@muratmaga](https://discourse.slicer.org/u/muratmaga)\
**Post date:** [May 6, 2026, 3:40pm UTC](https://discourse.slicer.org/t/idavlm-converter-not-aligning-landmarks-to-model/46940/2 "2026-05-06T15:40:08Z")

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We don’t really support the IdavLMConverter anymore, and soon will remove it. There is the similar functionality in SlicerMorph in the module `PlaceLandmarkGrid`. [Tutorials/GridBasedLandmarking at main · SlicerMorph/Tutorials · GitHub](https://github.com/SlicerMorph/Tutorials/tree/main/GridBasedLandmarking)

It might be LPS vs RAS issue, but again it is not supported. I suggest not using it.

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**Author:** ![ThomasVanParys](https://avatars.discourse-cdn.com/v4/letter/t/7ea924/32.png) [@ThomasVanParys](https://discourse.slicer.org/u/ThomasVanParys)\
**Post date:** [May 6, 2026, 6:22pm UTC](https://discourse.slicer.org/t/idavlm-converter-not-aligning-landmarks-to-model/46940/3 "2026-05-06T18:22:53Z")

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Thanks Murat,  
I find that SlicerMorph’s `PlaceLandmarkGrid` function struggles with even distribution of semi-landmarks within the patch and their projection onto a surface (such as a scapular fossa I am currently dealing with). Any tips with this other than manual adjustment and boosting the projection factor? Thanks!  
Tom

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**Author:** ![muratmaga](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/muratmaga/32/3622_2.png) [@muratmaga](https://discourse.slicer.org/u/muratmaga)\
**Post date:** [May 6, 2026, 7:21pm UTC](https://discourse.slicer.org/t/idavlm-converter-not-aligning-landmarks-to-model/46940/4 "2026-05-06T19:21:17Z")

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If you can share models and landmarks that goes with them, along with a screenshot of how you are placing the grid, I can take a look.

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<div class="post-metadata">

**Author:** ![ThomasVanParys](https://avatars.discourse-cdn.com/v4/letter/t/7ea924/32.png) [@ThomasVanParys](https://discourse.slicer.org/u/ThomasVanParys)\
**Post date:** [May 7, 2026, 8:25am UTC](https://discourse.slicer.org/t/idavlm-converter-not-aligning-landmarks-to-model/46940/5 "2026-05-07T08:25:56Z")

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Thanks Murat  
Actually, I have had a look and it seems to be working fine now(?!). Some scapulae are easier to apply patches to than others, however, my plan is to merge two smaller patches to minimise bending energy and complicated geometric spread over a single grid… I appreciate the help.

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<div class="post-metadata">

**Author:** ![muratmaga](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/muratmaga/32/3622_2.png) [@muratmaga](https://discourse.slicer.org/u/muratmaga)\
**Post date:** [May 7, 2026, 2:31pm UTC](https://discourse.slicer.org/t/idavlm-converter-not-aligning-landmarks-to-model/46940/6 "2026-05-07T14:31:45Z")

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> [@ThomasVanParys](#):
>
> Actually, I have had a look and it seems to be working fine now(?!). Some scapulae are easier to apply patches to than others, however, my plan is to merge two smaller patches to minimise bending energy and complicated geometric spread over a single grid… I appreciate the help.

I am glad to hear it is working. There are quite a bit of heuristics (such as projection factor) that depends on the scale of the data, and sometimes what we exposed on the UI is not within the range that is relevant for that specific data. I find it quite useful to give the source code to the LLM and explain problem show it visually and ask suggestions.