So I've been messing with SHOP networks and incorporating things I do in SOP VOPs into SHOPs. If I plug some of my own math into Base Color it invalidates the OpenGL diffuse and thus I can see what I'm doing in the viewport. I've been banging my head all day on how to expose ogl_diff so I can plug my nodes direct into it and restore my viewport. For that matter really, all the parameters under the OpenGL tab for a shader, where are they in VOPs?

The viewport looks at the OGL parameters on the material or SHOP, and not at all at the VOP network. You'll need to link ogl_diff to the VOP parameter that's responsible for generating it. This might mean adding a more complicated expression than just the ch() link.

We don't have VEX VOP to GLSL conversion; it's a very complicated problem to solve for most production cases, and some cases can't be solved at all.