# Models Edges

**URL:** https://discourse.vtk.org/t/models-edges/16376
**Category:** Support
**Created:** [April 9, 2026, 8:58am UTC](https://discourse.vtk.org/t/models-edges/16376 "2026-04-09T08:58:31Z")
**Posts on this page:** 5
**Page:** 1

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### Author: ![Xie](https://discourse.vtk.org/letter_avatar_proxy/v4/letter/x/ce73a5/32.png) [@Xie](https://discourse.vtk.org/u/Xie)
#### Post date: [April 9, 2026, 8:58am UTC](https://discourse.vtk.org/t/models-edges/16376/1 "2026-04-09T08:58:31Z")

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Hi,guys. I want to generate the contour of a bone model, similar to the effect shown below. I tried using vtkFeatureEdges, but the contour it produces is not what I want（the red ）. What should I do? Tks

 ![image](https://discourse.vtk.org/uploads/default/original/2X/9/9d2b230fc44412a347f2ab2d2c0a7aac2b46e2ed.jpeg)

 ![image](https://discourse.vtk.org/uploads/default/original/2X/c/c4e642496662149dae10a77db3b7779cee5bf1cc.jpeg)

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### Author: ![LucasGandel](https://discourse.vtk.org/user_avatar/discourse.vtk.org/lucasgandel/32/1831_2.png) [@LucasGandel](https://discourse.vtk.org/u/LucasGandel)
#### Post date: [April 10, 2026, 8:40am UTC](https://discourse.vtk.org/t/models-edges/16376/2 "2026-04-10T08:40:51Z")

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Hi, you could try to extract the isosurface of the bones to get a polydata and then apply the [outline glow](https://examples.vtk.org/site/Cxx/Rendering/OutlineGlowPass/) pass. Not sure if the pass blends well with volume rendering though.

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### Author: ![Xie](https://discourse.vtk.org/letter_avatar_proxy/v4/letter/x/ce73a5/32.png) [@Xie](https://discourse.vtk.org/u/Xie)
#### Post date: [April 10, 2026, 9:00am UTC](https://discourse.vtk.org/t/models-edges/16376/3 "2026-04-10T09:00:08Z")

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wawa，I tried this method, it worked!!! amzing!!! Thank u so much!!!😆 🥰

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### Author: ![Xie](https://discourse.vtk.org/letter_avatar_proxy/v4/letter/x/ce73a5/32.png) [@Xie](https://discourse.vtk.org/u/Xie)
#### Post date: [April 13, 2026, 1:37am UTC](https://discourse.vtk.org/t/models-edges/16376/4 "2026-04-13T01:37:52Z")

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Hello, thank you so much. I tried this solution, it can show edges, that’s really amzing. By the way, Is it possible that only show edges but no original polyData(actor). Looking forward for your reply.🥰

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### Author: ![sankhesh](https://discourse.vtk.org/user_avatar/discourse.vtk.org/sankhesh/32/73_2.png) [@sankhesh](https://discourse.vtk.org/u/sankhesh)
#### Post date: [April 14, 2026, 3:03am UTC](https://discourse.vtk.org/t/models-edges/16376/5 "2026-04-14T03:03:42Z")

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For just the edges, take a look at [`vtkSobelGradientMagnitudePass`](https://vtk.org/doc/nightly/html/classvtkSobelGradientMagnitudePass.html). Here’s an image from one of VTK tests that exercises it:

 ![](https://discourse.vtk.org/uploads/default/original/2X/0/0319ff7a84e70a1fc9aad96a66601463bd21a6ce.png)