# How to set center of rotation for linear transformation in GUI

**URL:** <https://discourse.slicer.org/t/how-to-set-center-of-rotation-for-linear-transformation-in-gui/10903>\
**Category:** Support\
**Tags:** registration, transforms\
**Created:** [March 30, 2020, 11:08am UTC](https://discourse.slicer.org/t/how-to-set-center-of-rotation-for-linear-transformation-in-gui/10903 "2020-03-30T11:08:15Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![Alex\_Vergara](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/alex_vergara/32/15205_2.png) [@Alex\_Vergara](https://discourse.slicer.org/u/Alex_Vergara)\
**Post date:** [March 30, 2020, 11:08am UTC](https://discourse.slicer.org/t/how-to-set-center-of-rotation-for-linear-transformation-in-gui/10903/1 "2020-03-30T11:08:15Z")

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When I use transformation module there is a way to rotate one volume to match the other, but I can’t control the center of rotation. I thought that by setting a fiducial point will do the trick but no.  
So, is there a way to set up the center of rotation? I just need to make a fiducial point the center of rotation

Wow! [2013!!!](https://mantisarchive.slicer.org/view.php?id=3155) I see this is already an [issue](https://github.com/Slicer/Slicer/issues/3155)

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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:** [March 31, 2020, 3:23am UTC](https://discourse.slicer.org/t/how-to-set-center-of-rotation-for-linear-transformation-in-gui/10903/2 "2020-03-31T03:23:43Z")

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We haven’t implemented this feature because in general you cannot achieve optimal spatial alignment by performing rotation around a single point.

You can rotate around a point as shown in this [example in the script repository](https://www.slicer.org/wiki/Documentation/Nightly/ScriptRepository#Rotate_a_node_around_a_specified_point) but I would recommend to use better registration methods (landmark registration, surface registration, intensity-based image registration, etc.).

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**Author:** ![juday](https://avatars.discourse-cdn.com/v4/letter/j/f07891/32.png) [@juday](https://discourse.slicer.org/u/juday)\
**Post date:** [March 31, 2020, 4:23pm UTC](https://discourse.slicer.org/t/how-to-set-center-of-rotation-for-linear-transformation-in-gui/10903/3 "2020-03-31T16:23:47Z")

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You can change the origin (around which volume rotates) of the volume in “Volume” module. Click on center volume to move the origin of the selected volume.

After centering the volume, linear transforms should work in expected way.

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**Author:** ![pieper](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/pieper/32/8_2.png) [@pieper](https://discourse.slicer.org/u/pieper)\
**Post date:** [March 31, 2020, 7:45pm UTC](https://discourse.slicer.org/t/how-to-set-center-of-rotation-for-linear-transformation-in-gui/10903/4 "2020-03-31T19:45:22Z")

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You can also set up a transform hierarchy which allows you to simulate various robot arm-like motions.