# Can I use OpenGL compute shaders in VTK program?
**URL:** https://discourse.vtk.org/t/can-i-use-opengl-compute-shaders-in-vtk-program/4055
**Category:** Support
**Created:** [August 24, 2020, 10:18am UTC](https://discourse.vtk.org/t/can-i-use-opengl-compute-shaders-in-vtk-program/4055 "2020-08-24T10:18:41Z")
**Posts on this page:** 7
**Page:** 1
### Author:  [@yuxing55555](https://discourse.vtk.org/u/yuxing55555)
#### Post date: [August 24, 2020, 10:18am UTC](https://discourse.vtk.org/t/can-i-use-opengl-compute-shaders-in-vtk-program/4055/1 "2020-08-24T10:18:41Z")
VTK9.0 use OpenGL2 at backend, and use GetOpenGLVersion result is 4.4.
i found vtkShader not contain compute shader.
Does anyone has any example to use compute shader?
thank you!
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### Author:  [@Paulo\_Carvalho](https://discourse.vtk.org/u/Paulo_Carvalho)
#### Post date: [August 24, 2020, 3:28pm UTC](https://discourse.vtk.org/t/can-i-use-opengl-compute-shaders-in-vtk-program/4055/2 "2020-08-24T15:28:55Z")
Hi, friend,
Since your post was not much specific, I can only suggest this example here: [https://gitlab.kitware.com/vtk/vtk/blob/v7.0.0.rc2/Rendering/OpenGL2/Testing/Cxx/TestUserShader2.cxx](https://gitlab.kitware.com/vtk/vtk/blob/v7.0.0.rc2/Rendering/OpenGL2/Testing/Cxx/TestUserShader2.cxx) . It includes a basic example in glsl language.
regards,
Paulo
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### Author:  [@Lfx\_Paul](https://discourse.vtk.org/u/Lfx_Paul)
#### Post date: [August 24, 2020, 3:31pm UTC](https://discourse.vtk.org/t/can-i-use-opengl-compute-shaders-in-vtk-program/4055/3 "2020-08-24T15:31:14Z")
Indeed, there is no GL\_COMPUTE\_SHADER in the Compile function of vtkShader. If I remember well VTK use openGL version 3.2. If you want to create a compute shader, you must compile it yourself, as well as call glComputeDispatch by hand
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### Author:  [@Lfx\_Paul](https://discourse.vtk.org/u/Lfx_Paul)
#### Post date: [August 24, 2020, 3:34pm UTC](https://discourse.vtk.org/t/can-i-use-opengl-compute-shaders-in-vtk-program/4055/4 "2020-08-24T15:34:58Z")
This is the method to use a user custom shader, but this won’t work in case of a GL\_COMPUTE\_SHADER (introduced in OpenGL version 4.3). This seems to work only for vertex and fragment shader
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### Author:  [@yuxing55555](https://discourse.vtk.org/u/yuxing55555)
#### Post date: [August 25, 2020, 1:07am UTC](https://discourse.vtk.org/t/can-i-use-opengl-compute-shaders-in-vtk-program/4055/5 "2020-08-25T01:07:53Z")
thanks for the reply, I know this. You can also find some shader-related examples here, but there are no compute shader-related examples.
[https://lorensen.github.io/VTKExamples/site/Cxx/#shaders](https://lorensen.github.io/VTKExamples/site/Cxx/#shaders)
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### Author:  [@yuxing55555](https://discourse.vtk.org/u/yuxing55555)
#### Post date: [August 25, 2020, 1:08am UTC](https://discourse.vtk.org/t/can-i-use-opengl-compute-shaders-in-vtk-program/4055/6 "2020-08-25T01:08:40Z")
thanks for the reply.Yes, vtkShader does not include GL\_COMPUTE\_SHADER. I myself use vtk9.0.0 compiled by mingw4.8.2, and then I use the GetOpenGLVersion method of vtkWin32OpenGLRenderWindow to get the opengl version 4.4. When I compiled vtk9.0.0, I didn’t find a way to set the opengl version. . I will try the way you said,thank you.
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### Author:  [@Jens\_Munk\_Hansen](https://discourse.vtk.org/u/Jens_Munk_Hansen)
#### Post date: [November 14, 2023, 7:21pm UTC](https://discourse.vtk.org/t/can-i-use-opengl-compute-shaders-in-vtk-program/4055/7 "2023-11-14T19:21:44Z")
I know this is an old thread, but in the latest master, compute shaders are now supported and in `vtk/Rendering/OpenGL2/Testing/Cxx/TestComputeShader.cxx` a test is included.