Introduction ============ PythonCAD is an open-source CAD package built designed around Python. As such, it aims to be a fully scriptable and customizable CAD program. It is initially designed to run under Linux, one of the BSD flavors, or Unix. Using an established, powerful, and expressive language like Python as the core of the program saves an enormous amount of work for developers and, for users who are already familiar with Python, you don't have to try and learn a new language if you want to extend or customize the code. If you've never written Python code before, there are extensive resources available for you. A good place to start is at the Python home page ... http://www.python.org Goals ===== The primary design goal is to provide a good CAD package. The open-source world has been moving steadily from providing superior tools for proprietary systems (i.e. GCC), to world-class operating systems (i.e. Linux), and has advanced remarkably in providing complete desktop environments (GNOME and KDE). It is hoped that PythonCAD will grow to be an excellent addition to the desktop programs now available for users of open-source software. A design goal with the program code is to keep the user interface completely separated from the back end or generic code. In doing so, it should be possible for developers to write code porting PythonCAD to their chosen interface with less work. The initial release is written using GTK-2.0 as the interface (utilizing the PyGTK library). The addition of a front end utilizing the Py-Objc bindings on Mac OS X and Cocoa demonstrates that this approach of separating the interface from the core program is a viable approach of application design. It is hoped that interfaces for GNOME, QT, KDE, and other packages will eventually be added to PythonCAD. A second code design goal is to write a powerful graphical program without writing much, if any, C or C++ code. The Python language frees the programmer from many of the difficulties that are associated with C (memory allocation, buffer handling, etc.) or C++ code (i.e. compiler and platform issues). No language is perfect, but it is hoped that PythonCAD can demonstrate that choosing Python as the primary language for development provides good performance, ease of maintenance, and a fun language to work with. Requirements ============ Python: Version 2.2 at a minimum, with the zlib module. At the time of the thirtieth release the final 2.2 based release is 2.2.3, the (final?) 2.3 release is 2.3.5, and the latest 2.4 release is 2.4.2. PythonCAD should run without problem in any of the releases. There are as yet no plans to raise the minimum Python release to the 2.3 series. PyGTK-2.0: Version 1.99.16 at least, with version 2.0 recommended. The PyGTK developers have released PyGTK-2.6, which has support for more features in the latest GTK code. The PyGTK-2.4 release as well as the PyGTK-2.2 release work also, but these releases are tied to older GTK releases and are consequently in maintenance mode (at best). GTK and its dependencies: It is strongly recommended to use the latest release of GTK, Pango, ATK, and Glib. At the thirtieth PythonCAD release, GTK is at version 2.8.16, Pango is version 1.12.0, ATK is release 1.11.3, and Glib is release 2.10.1. The fifteenth release of PythonCAD offered a native Cocoa interface utilizing the Py-Objc bridge for Mac OS X users. Unfortunately the developer maintaining the Cocoa interface is no longer able to do so, and current PythonCAD releases do not work with the Py-Objc bindings. Developers wishing to pick up this code and maintain it would be welcomed. License ======= PythonCAD is distributed under the terms of the GNU General Public License (GPL).