# Intersection lines not show up

**URL:** <https://discourse.slicer.org/t/intersection-lines-not-show-up/35851>\
**Category:** Support\
**Created:** [May 1, 2024, 1:26pm UTC](https://discourse.slicer.org/t/intersection-lines-not-show-up/35851 "2024-05-01T13:26:48Z")\
**Posts on this page:** 8\
**Page:** 1

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**Author:** ![Ben\_Fong](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/ben_fong/32/67953_2.png) [@Ben\_Fong](https://discourse.slicer.org/u/Ben_Fong)\
**Post date:** [May 1, 2024, 1:26pm UTC](https://discourse.slicer.org/t/intersection-lines-not-show-up/35851/1 "2024-05-01T13:26:48Z")

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I am a novice user. I tried “basic + intersection” or “small basic + intersection”, the crosshair showed up, but the intersection did not, what should I do? Please help. Thanks. (Windows 10 & Mac Sonoma, version 5.6.2).

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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:** [May 1, 2024, 6:58pm UTC](https://discourse.slicer.org/t/intersection-lines-not-show-up/35851/2 "2024-05-01T18:58:55Z")

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Basic with intersection should look like this:

![image](https://us1.discourse-cdn.com/flex002/uploads/slicer/original/3X/7/a/7acc7e9d0a2a95735835fce91881efe2e22842e5.png)

No intersection should look like this:

![image](https://us1.discourse-cdn.com/flex002/uploads/slicer/original/3X/1/e/1e4f5b670dbd4e8bac2e5b05864569de9dd9847f.png)

Small basic with intersection like this:

![image](https://us1.discourse-cdn.com/flex002/uploads/slicer/original/3X/3/a/3a8163b7e93bb67a71591f268741117b314c8eaa.png)

Is that not what you see?

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**Author:** ![Ben\_Fong](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/ben_fong/32/67953_2.png) [@Ben\_Fong](https://discourse.slicer.org/u/Ben_Fong)\
**Post date:** [May 1, 2024, 10:28pm UTC](https://discourse.slicer.org/t/intersection-lines-not-show-up/35851/4 "2024-05-01T22:28:38Z")

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Thanks for yor information. Yes, it is, sorry that probably my terms are not correct. I want to see the cross reference lines in the images when I scroll through them. I could see it in the past year ago, but not now after update. What setting am I missed? Thanks.

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**Author:** ![Ben\_Fong](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/ben_fong/32/67953_2.png) [@Ben\_Fong](https://discourse.slicer.org/u/Ben_Fong)\
**Post date:** [May 1, 2024, 10:36pm UTC](https://discourse.slicer.org/t/intersection-lines-not-show-up/35851/5 "2024-05-01T22:36:46Z")

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I am looking for the cross reference lines that showing the real time position of the slice of the image in other views when I scroll. The crosshair is a mark that stays at one spot. The crosshair line function normal, but is not I want. Thanks.

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**Author:** ![cpinter](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/cpinter/32/7995_2.png) [@cpinter](https://discourse.slicer.org/u/cpinter)\
**Post date:** [May 2, 2024, 11:48am UTC](https://discourse.slicer.org/t/intersection-lines-not-show-up/35851/6 "2024-05-02T11:48:45Z")

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It seems to me that what you need are the slice intersections. There has been a rework around crosshairs and slice intersections, and now it has its own button and settings in the toolbar:  
 ![image](https://us1.discourse-cdn.com/flex002/uploads/slicer/original/3X/3/0/3039ea0d137413a848bb98b4193e1c5c7f53aee7.png)

I think it would be a great community contribution if you could add a paragraph about this below this one:  
[https://slicer.readthedocs.io/en/latest/user\_guide/user\_interface.html#view-cross-reference](https://slicer.readthedocs.io/en/latest/user_guide/user_interface.html#view-cross-reference)  
Please let us know if you have an hour for this. We’re happy to provide you guidance. Thanks!

Of course also let me know if this is not what you needed.

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**Author:** ![Ben\_Fong](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/ben_fong/32/67953_2.png) [@Ben\_Fong](https://discourse.slicer.org/u/Ben_Fong)\
**Post date:** [May 2, 2024, 12:12pm UTC](https://discourse.slicer.org/t/intersection-lines-not-show-up/35851/7 "2024-05-02T12:12:14Z")

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Thanks for your information.  
I realized the problem.  
Yes, it is what I am looking for, but I just failed to activate it correctly.  
Instead of directly pressing on the button, I went to the sideway arrow button and clicked on the interaction, I thought it would activate the cross-reference at the same time, which is not. I got this wrong impression because if I choose an option for the nearby crosshair button, the crosshair is activated.  
Now I know that I simply need to press directly on the button to get the function, the “interaction” is the newly added function to the cross-reference line, clicking it does not activate the cross-reference function.  
Thanks a lot.

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<div class="post-metadata">

**Author:** ![Ben\_Fong](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/ben_fong/32/67953_2.png) [@Ben\_Fong](https://discourse.slicer.org/u/Ben_Fong)\
**Post date:** [May 2, 2024, 12:29pm UTC](https://discourse.slicer.org/t/intersection-lines-not-show-up/35851/8 "2024-05-02T12:29:47Z")

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I just suggested to insert two lines (97 & 98) to the document:

 ![2024-05-02_202704](https://us1.discourse-cdn.com/flex002/uploads/slicer/original/3X/0/5/05981a1f66256a4b8f9b1ab58b38df145ed2fc02.jpeg)  
Thanks.

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<div class="post-metadata">

**Author:** ![cpinter](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/cpinter/32/7995_2.png) [@cpinter](https://discourse.slicer.org/u/cpinter)\
**Post date:** [May 2, 2024, 12:57pm UTC](https://discourse.slicer.org/t/intersection-lines-not-show-up/35851/9 "2024-05-02T12:57:15Z")

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Thanks for the report! I think your suggestion for change would be a mistake, as that paragraph is about the Crosshair, and now we have a separate Slice intersections feature. We’ll need a new paragraph.

Edit: It may actually be okay, I did not consider it in depth, because, again, the most confusing part is that we don’t have it documented that there are two different functions now instead of one.