Bruno Postle has proposed an interesting CAD file format, complete with proof of concept application written in perl.
Concept
- If it can be a separate file, then that's what it should be.
- Fast efficient saving
- Fast efficient reading
- Infinite undo
- Changes are easily encapsulated and portable
- Full version tagging and release management
- Embedded resources are kept external
- Fine-grained permissions system
- Platform-independent data
- Object-oriented data
The beauty of this concept is the leverage of existing tools (modern filesystems, versioning, perl/tk, etc.) to provide an elegant example of what is now possible but rarely implemented.
With CVS, multiple authors can work on a single CAD project complete with real time display of all changes as they happen.
Each element of the drawing (an object perhaps; line, circle, etc.) can be described in a simple and human readable text file:
Content-Type: application/drawing; class=line/plain Version: 1.0 Units: millimetres 0: 10 0: 20 0: 0 1: 10 1: 40 1: 0 License: http://creativecommons.org/licenses/sa/1.0/ Copyright: Jane Doe <jane@example.com>
Groups of these files make an application which can later be used as a reference, providing object oriented approach to CAD design.
Making the hard things possible...
The author makes these points clear in about "400 lines of perl code." I downloaded the proof of concept application, installed the few modules necessary and it worked perfectly on my Fedora FC2 box. The concepts demonstrated in perl may not provide for the needs of a commercial CAD application and the author states (in various POD comments) that perl is not the solution for long term CAD implementations.
What is profoundly important are the concepts demonstrated. Faced with thousands of text files, perl was the natural solution for parsing and display of this information. With a bit more work, I am certain this proof of concept could surprise more than I with the possibilities of perl/tk and GUI applications to visual data display.