Drafting and design software.
AutoCAD is produced by Autodesk Inc. It is a base product for many of their software offerings that are designed for specific tasks such as architectural, mechanical and civil drafting. AutoCAD is customizable by means of several APIs.
- Autolisp - A flavor of LISP.
- VBA - Microsoft VBA became available as an API during the release of AutoCAD 14 prior to 2000. Autodesk has warned that VBA will not be supported in releases after 2012... but it is, even in native 64-bit for the 1st time in v2014.
- Managed .NET - A managed .NET API is currently the customization platform of choice for many AutoCAD programmers. Of the .NET languages C# is currently the most popular but VB.NET has a stronger-than-usual following because of AutoCAD's VBA history.
- the JavaScript API was introduced in v2014.
- ObjectARX/ObjectDBX - A native C++ based API that became available during the release of AutoCAD 13. Less popular than the .NET API because it requires writing much more code and more complex code to accomplish most tasks. Some types of projects (complex custom objects) can only be done via this API.
Autodesk also licenses two stand-alone AutoCAD environments to develop on top of, RealDWG and AutoCAD OEM. OEM has a user interface and RealDWG does not. The licensing model for each is very different - OEM is licensed as a percentage of each sale, RealDWG has fixed license costs.
There is an independent reverse-engineered library that is compatible with AutoCAD made by the Open Design Alliance. Compatibility can lag a little when Autodesk does its 3-yearly binary shuffle and changes the file format. AutoCAD v 2013 changed the application's internal structure, as well as the file format.
The ODA is not open-source nor is it free (as in beer but it is free as in speech) and is not necessarily cheaper than Autodesk's licensing, depending on if / how many sales you make. ODA's Teigha is used as the basis for products like IntelliCAD etc. You can build stand-alone applications on it.
Resources
