AutoCAD is one of the most open architecture-designed CAD/CAE/CAM systems with a large variety of programming options on the market. The base AutoCAD package (not AutoCAD LT, but regular AutoCAD) ...
VBA runs inside AutoCAD; when the AutoCAD drawing editor is active, there is always a current drawing. The current drawing (or document) is defined as an object with the name ThisDrawing in the VBA ...