How to set custom shader with VTK 8.1(C++)

Support
1

Hi,everyone
How can i set custom shader with VTK8.1?
I know it’s probably using vtkShaderProgram,but i can’t find any example.
Could you please provide insights for achieving this? Your guidance would be greatly appreciated.

2

Hello,

To set shaders for your mapper in VTK 8.1, please take a look at Rendering/OpenGL2/Testing/Cxx/TestUserShader.cxx · v8.1.0 · VTK / VTK · GitLab and Rendering/OpenGL2/Testing/Cxx/TestUserShader2.cxx · v8.1.0 · VTK / VTK · GitLab .

best,

PC

3

Thanks for your reply.
I can’t find the method of AddShaderReplacement,but i will try SetVertexShaderCode and SetFragmentShaderCode.
Hope it works.
Thanks again for your help

4

Hello,

AddShaderReplacement() belongs to the vtkOpenGLShaderProperty class, which was introduced in VTK 9.

best,

PC

5

Hello,
Thanks for your reply.
I use AddVertexShaderReplacement and AddFragmentShaderReplacement in VTK(9.3.0), which can work well.But while replaced with SetFragmentShaderCode and SetVertexShaderCode, if i set opacity and get closer to the model, it will be low FPS.
In NVIDIA Nsight Graphics, i find this:

image
image519×889 31 KB

glClear() and Draw many times, could you tell me what’s wrong with it.
It will have the same issue in VTK(8.1.0).
Any reply would be greatly appreciated

6

Sorry,i found this was a Depthpeeling problem, I did not set the reference in the shader

7

How do I set the uniform attribute in VTK(8.1.0).
The method of SetUniform is only found in vtkShaderProgram, but i don’t know how to use vtkShaderProgram.No other method related to ShaderProgram was found.
Any reply would be greatly appreciated