# Link disappears when attempting to move it

**URL:** https://discourse.vtk.org/t/link-disappears-when-attempting-to-move-it/9036
**Category:** Web
**Created:** [July 28, 2022, 2:33pm UTC](https://discourse.vtk.org/t/link-disappears-when-attempting-to-move-it/9036 "2022-07-28T14:33:16Z")
**Posts on this page:** 5
**Page:** 1

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### Author: ![astrid-d](https://discourse.vtk.org/user_avatar/discourse.vtk.org/astrid-d/32/5564_2.png) [@astrid-d](https://discourse.vtk.org/u/astrid-d)
#### Post date: [July 28, 2022, 2:33pm UTC](https://discourse.vtk.org/t/link-disappears-when-attempting-to-move-it/9036/1 "2022-07-28T14:33:16Z")

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Hello, I’m completely new to vtk.js and I’m trying to model an industrial robot. I have added sliders with eventlisteners so that each link of the robot can rotate by dragging the slider. It works for most links, while some just disappear when trying to move them. I understand that this is a poor problem description but I’ll just shoot my shot - has anyone ever encountered this issue? Has something crashed? Does anyone have an idea of what the problem could be or how to fix it? (I’m not sure if they actually disappear or if they mysteriously become translucent.)  
Any advice would be highly appreciated.

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### Author: ![finetjul](https://discourse.vtk.org/user_avatar/discourse.vtk.org/finetjul/32/154_2.png) [@finetjul](https://discourse.vtk.org/u/finetjul)
#### Post date: [July 28, 2022, 4:08pm UTC](https://discourse.vtk.org/t/link-disappears-when-attempting-to-move-it/9036/2 "2022-07-28T16:08:13Z")

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Have you considered resetting the camera ? e.g.`vtkRenderer.resetCamera()` or `vtkRenderer.resetCameraClippingRange()`

Some screenshots would be useful to “see” what happens.

Hth

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### Author: ![astrid-d](https://discourse.vtk.org/user_avatar/discourse.vtk.org/astrid-d/32/5564_2.png) [@astrid-d](https://discourse.vtk.org/u/astrid-d)
#### Post date: [July 29, 2022, 11:22am UTC](https://discourse.vtk.org/t/link-disappears-when-attempting-to-move-it/9036/3 "2022-07-29T11:22:34Z")

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Thanks for the reply Julien. I tried resetting the camera but nothing changed.  
Here are some screenshots from when I’m moving one part that works, and then when I’m trying to move the part that disappears.

 ![Screenshot from 2022-07-29 13-19-06](https://discourse.vtk.org/uploads/default/original/2X/8/8b95fbb74552b097e1158632435f78d7bb47ff75.png)  
 ![Screenshot from 2022-07-29 13-20-30](https://discourse.vtk.org/uploads/default/original/2X/9/9c939f52b53e829b995857126c28f8ab2425c2ee.png)  
 ![Screenshot from 2022-07-29 13-20-44](https://discourse.vtk.org/uploads/default/original/2X/f/fbd577c219bd061673dbf962a7d51373c4ea6a9f.png)

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### Author: ![finetjul](https://discourse.vtk.org/user_avatar/discourse.vtk.org/finetjul/32/154_2.png) [@finetjul](https://discourse.vtk.org/u/finetjul)
#### Post date: [July 29, 2022, 12:18pm UTC](https://discourse.vtk.org/t/link-disappears-when-attempting-to-move-it/9036/4 "2022-07-29T12:18:25Z")

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How do you apply the “rotation” to your part ? Through the UserMatrix ?  
What happens if your transforms are very small ?

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### Author: ![zhangzhiyu](https://discourse.vtk.org/letter_avatar_proxy/v4/letter/z/ce73a5/32.png) [@zhangzhiyu](https://discourse.vtk.org/u/zhangzhiyu)
#### Post date: [December 23, 2022, 2:22am UTC](https://discourse.vtk.org/t/link-disappears-when-attempting-to-move-it/9036/5 "2022-12-23T02:22:46Z")

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I have the same problem.  
when i use` transform->RotateX()` for the actor. sometimes, the actor disappears.  
Who knows the cause of the problem. Any heip would be appreciated.