It looks like bits of actual C++ code. It has class initializations and functions. Don't think anyone other than IC can make much sense of it, but they probably shouldn't be messed with

High-level Pixel Shader Language (HLSL) : They partially control the rendering of a scene.

I think its coded in C# rather than C++ it hooks into the DirectDraw API somehow.

I have had a play with them a little there needs to be some backup documentation from IC really to make more sense of these but you can make out parts that refer to object and global space easily enough.