# Can not find vtkVolumeRayCastMIPFunction in vtk 9.1

**URL:** https://discourse.vtk.org/t/can-not-find-vtkvolumeraycastmipfunction-in-vtk-9-1/7908
**Category:** Support
**Created:** [February 24, 2022, 6:35am UTC](https://discourse.vtk.org/t/can-not-find-vtkvolumeraycastmipfunction-in-vtk-9-1/7908 "2022-02-24T06:35:21Z")
**Posts on this page:** 1
**Page:** 1

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### Author: ![zhang-qiang-github](https://discourse.vtk.org/user_avatar/discourse.vtk.org/zhang-qiang-github/32/2519_2.png) [@zhang-qiang-github](https://discourse.vtk.org/u/zhang-qiang-github)
#### Post date: [February 24, 2022, 6:35am UTC](https://discourse.vtk.org/t/can-not-find-vtkvolumeraycastmipfunction-in-vtk-9-1/7908/1 "2022-02-24T06:35:21Z")

</div>

I want to implement maximum intensity projection in my project, and `vtkVolumeRayCastMIPFunction` is what I want. However, I can not find it in vtk 9.1. Is there any method can replace `vtkVolumeRayCastMIPFunction`? Or how can I implement MIP in vtk 9.1?

Any suggestion is appreciated~~~