Near two years ago I wrote a post about CAD file formats. I defended the DGN format against DWG or DXF. Then I thought the Open Design Alliance was a good idea.
But since that post to now I began to investigate in order to write a translator from DGN V8 for Blender. My first step was towards the Open Design Alliance, but there I couldn’t find free libs nor DGN V8 specs. ODA has an interesting point of beginning (if your file formats are not free you can’t own your works). But they are not interested en free (as in freedom) software.
So I aimed to Bentley’s OpenDGN Initiative. All my attempts finished in a ‘forbidden’ web page. Then I exchanged a pair of mails with the person at the charge, finally I couldn’t got the DGN V8 specs. He stopped to answer my emails. I found similar experiencies of people looking for this document.
As it seems it is impossible to find the DGN V8 specifications as I can find the DGN V7/ISFF, I conclude OpenDGN is not so open as Bentley pretends. So it is a bad idea to found any project in DGN V8 (closed specs), DWG (closed specs, heavy drm-zed format) and DXF (poor format, not standard at all).
Via Martín who writes in gpul’s blog I discovered a recent project which target is to design a really open CAD file format. It seems there are interesting discussions about it.
Maybe you think a CAD format is a too specific field to work. But you must think in the roads you drive on, the buildings you live and work, the engines that move you, the networks you connect to. Think about it, and you will see a world to free.