# where is ospray/ospray.h?
**URL:** https://discourse.vtk.org/t/where-is-ospray-ospray-h/1173
**Category:** Support
**Created:** [June 19, 2019, 7:07am UTC](https://discourse.vtk.org/t/where-is-ospray-ospray-h/1173 "2019-06-19T07:07:17Z")
**Posts on this page:** 5
**Page:** 1
### Author:  [@tdchen](https://discourse.vtk.org/u/tdchen)
#### Post date: [June 19, 2019, 7:07am UTC](https://discourse.vtk.org/t/where-is-ospray-ospray-h/1173/1 "2019-06-19T07:07:17Z")
I tried to compile VTK with OSPRay, but it failed.
It said “cannot open source file ospray/ospray.h”
And this file indeed not existed in VTK directory.
What I should do in addition to check the Module\_vtkRenderingOSPRay in CMake interface?
Thanks in advance.
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### Author:  [@ben.boeckel](https://discourse.vtk.org/u/ben.boeckel)
#### Post date: [June 19, 2019, 12:54pm UTC](https://discourse.vtk.org/t/where-is-ospray-ospray-h/1173/2 "2019-06-19T12:54:38Z")
OSPRay needs to be provided externally from VTK. It is available here: [https://github.com/ospray/ospray](https://github.com/ospray/ospray)
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### Author:  [@tdchen](https://discourse.vtk.org/u/tdchen)
#### Post date: [June 20, 2019, 8:05am UTC](https://discourse.vtk.org/t/where-is-ospray-ospray-h/1173/3 "2019-06-20T08:05:07Z")
Thank you very much ben.
I think we should:
1)Download OSPRay and Install it.
2) Select the Module\_vtkRenderingOSPRay in CMake interface
3)Input the OSPRAY\_BUILD\_DIR in CMake.
Are These right?
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### Author:  [@ben.boeckel](https://discourse.vtk.org/u/ben.boeckel)
#### Post date: [June 20, 2019, 11:34am UTC](https://discourse.vtk.org/t/where-is-ospray-ospray-h/1173/4 "2019-06-20T11:34:12Z")
I suspect CMake will want `OSPRay_DIR` to point to the path containing the `ospray-config.cmake` (or `OSPRayConfig.cmake`) file. But that list otherwise looks good.
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### Author:  [@tdchen](https://discourse.vtk.org/u/tdchen)
#### Post date: [June 21, 2019, 2:30am UTC](https://discourse.vtk.org/t/where-is-ospray-ospray-h/1173/5 "2019-06-21T02:30:33Z")
Hi, Ben.
I’ll try it.
Thank you.