Vip_wrapper_for_c_func

I recently purchased the De2115 board and run through the demonstration of VIP Camera. When I try to understand the C coding of main.c. I got a lots of functions. I located them in the workspace but the functions are mostly no comments and I have no idea what they did. Like VIP_WRAPPER_FOR_C_FUNC have couple of functions on frame reading and manipulation that I might need but I have no idea how to use the function. Is there any proper documentation on these functions?