Documentation for vertexMC, normalMC, MCDCMatrix, MVCMatrix.

I am starting my shader development in VTK. Earlier, I had some knowledge on the built-in vertex shader variables like gl_ModelViewMatrix. However, those variables are no longer appearing valid in my python based VTK shader code. I think the new ones are vertexMC, normalMC, MCDCMatrix, MVCMatrix. etc. The problem is I could not find any good documentation or examples to understand these variables. Can someone help me in understanding these variable or point me to some relevant documentation.

Every input variables are suffixed with its reference frame, so vertexMC means vertex in ModelCoordinates.
All the matrices are the transformation matrix from a reference to another: MCDCMatrix means ModelCoordinates to DeviceCoordinates matrix.
Here is the full list:

  • MC: Model coordinates
  • WC: World coordinates
  • VC: View coordinates
  • DC: Device coordinates

So, the equivalent of gl_ModelViewMatrix is MCVCMatrix.

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