Coding-style for dictionaries should be  parameter.get("Camera", )
To be able to catch undefined/broken parameters and avoid program interruption etc. just because something couldn't be found. As it would if you're using attributes.

How do you find out which parameters are available with an object? Something like dict.keys() for objects?

There is not more typing. Each line can be copied. Just the keywords have to be changed.

Simple iteration over a parameter dictionary where possible if an entry would carry his own output-format (there are just a few) and his default value to fallback in case of errors. Even an object able to output what it stores in the right format.

Another advantage of dictionaries: It's possible to move parts around without the need of an additional lib or user-defined object. Dictionaries are already there and anybody is familar with their use without further explanation about the object holding the parameters. With something like this only a few lines where needed to output the parameters.

Anything would be easier if XML where used insteed of spreading things around in several files (by the way: what about different languages, tooltips, help, whatever).

I go on with what I do because a few posts earlier I promised a GUI for this weekend to play with. Not mutch, but enough to try a few things out.

More interesting than a full working GUI would be to have the material export without errors. Better a default material and a hint than an interrupted script. The average user has only a bad chance to come out with something in case of complex materials with the actual version.

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