ScrollingTrick was written in C as example code. It was never designed to be reusable. (In fact, I couldn't write it in AmigaE no matter how hard I tried because the library mode is broken beyond repair in the compiler.)
Why am I doing this in C? It compiles better than AmosPro, supports inline Assembly better than AmosPro and most importantly, can bang the hardware without having to disable all the high-level features of AmosPro and litter my code with Exec library calls and wierd banks whose only purpose is to emulate structure functions that are natively supported in C.
Why as a shared library? It can be used from any language you choose, as many times in the same code as you choose. Many languages (including Assembly and AmigaE) have utilities for importing shared library support from the FD file (FD2Pragma
for example). But best of all, just by swapping the shared library for one written for graphics cards, you instantly have graphics card support without even trying!