# Detect the collosion of models, and change model outlook realtime
**URL:** https://discourse.vtk.org/t/detect-the-collosion-of-models-and-change-model-outlook-realtime/6778
**Category:** Support
**Created:** [October 8, 2021, 1:14am UTC](https://discourse.vtk.org/t/detect-the-collosion-of-models-and-change-model-outlook-realtime/6778 "2021-10-08T01:14:50Z")
**Posts on this page:** 7
**Page:** 1
### Author:  [@xianger.qi](https://discourse.vtk.org/u/xianger.qi)
#### Post date: [October 8, 2021, 1:14am UTC](https://discourse.vtk.org/t/detect-the-collosion-of-models-and-change-model-outlook-realtime/6778/1 "2021-10-08T01:14:50Z")
Hi:
Thanks for your reading. There are a question confused me, there are a femur model, and probe model. I control the probe to grind the femur. I can capture the collision caused by probe and femur. BUT I want to change the femur model outlook realtime. JUSH LIKE BELOW PICTURE
the white part is femur bone, and the green part is grinded region, if the probe model contacts the green part, the triangle cell will be change, the green part will disappear gradually.
how can i implement this effect?
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### Author:  [@Andrew](https://discourse.vtk.org/u/Andrew)
#### Post date: [October 8, 2021, 4:30am UTC](https://discourse.vtk.org/t/detect-the-collosion-of-models-and-change-model-outlook-realtime/6778/2 "2021-10-08T04:30:04Z")
We implement this over at [iMSTK](https://gitlab.kitware.com/iMSTK/iMSTK) (which uses VTK). And coincidently even do erosion on a femur bone. See this [example](https://gitlab.kitware.com/iMSTK/iMSTK/-/tree/master/Examples/FemurCut). We use a chunking approach to do it at super fast rates (\>1000hz).
Here’s an old Blog Post With Femur Bone Erosion: [iMSTK 4.0 Released - Kitware Blog](https://blog.kitware.com/imstk-release-4-0/)
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### Author:  [@xianger.qi](https://discourse.vtk.org/u/xianger.qi)
#### Post date: [October 8, 2021, 4:37am UTC](https://discourse.vtk.org/t/detect-the-collosion-of-models-and-change-model-outlook-realtime/6778/3 "2021-10-08T04:37:14Z")
Thanks a lot!! That’s what i want effect , i will read this now
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### Author:  [@xianger.qi](https://discourse.vtk.org/u/xianger.qi)
#### Post date: [October 9, 2021, 3:41am UTC](https://discourse.vtk.org/t/detect-the-collosion-of-models-and-change-model-outlook-realtime/6778/4 "2021-10-09T03:41:49Z")
i want to run the example: FemurCut , so i install the openhaptics and geomagic\_touch\_device\_driver, in the “/opt/openhaptics” and “opt/geomagic\_touch\_device\_driver”, then i change cmake variable “iMSTK\_USE\_OpenHaptics” to “ON” and run cmake …/iMSTK. The terminal print error “cant find openHaptics”
how can i fix that? Thanks for your help!
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### Author:  [@xianger.qi](https://discourse.vtk.org/u/xianger.qi)
#### Post date: [October 9, 2021, 7:03am UTC](https://discourse.vtk.org/t/detect-the-collosion-of-models-and-change-model-outlook-realtime/6778/5 "2021-10-09T07:03:56Z")
my os is ubuntu 18.04, Is this os can support external package: OpenHaptics ？ I found the codes in External\_OpenHaptics.cmake file.
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### Author:  [@Andrew](https://discourse.vtk.org/u/Andrew)
#### Post date: [October 9, 2021, 8:02pm UTC](https://discourse.vtk.org/t/detect-the-collosion-of-models-and-change-model-outlook-realtime/6778/6 "2021-10-09T20:02:02Z")
We don’t support OpenHaptics on Linux, only on Windows. Though if you wanted to contribute any code to iMSTK to get it working on Linux feel free to submit an MR. But for further discussion and iMSTK related question, please post this over on the [imstk forums](https://discourse.kitware.com/c/imstk/9).
Also FindOpenHaptics.cmake searches for OpenHaptics via a system variable that is created by the installer when installing open haptics (OH\_SDK\_BASE).
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### Author:  [@xianger.qi](https://discourse.vtk.org/u/xianger.qi)
#### Post date: [October 11, 2021, 3:51am UTC](https://discourse.vtk.org/t/detect-the-collosion-of-models-and-change-model-outlook-realtime/6778/7 "2021-10-11T03:51:42Z")
Thanks a lot, Can you simply describe the method to implement below example? 