AC's Tech for the Commodore Amiga was technically oriented quarterly publication for the Commodore Amiga, This issue is from March to May 1991 and includes the following:
Features
CAD Application Design: Part I - World and View Transforms - The first of a two part series covering the basic procedures used in vector-based two-dimensional CAD systems. Topics covered include cartesian coordinates and vectors, CAD system mathematics, transforming world coordinates, and more.
Interfacing Assembly Language Applications to ARexx - A tutorial for adding ARexx calls to assembly language programs. ARexx is the Amiga's native scripting language.
Adding Help to Applications Easily - A guide to adding 'on-line' help to your own programs.