Kevin
> These are hard problems without easy answers.
>
> There might be a solution to this interrelated set of problems. The
> first part of the solution lies in specifying the characteristics of a
> "Building-Block". The second part of the solution is retrieving
> "building-blocks" based on characteristics.
>
this is a good solution, if your "building blocks" are small
enough and not entire objects.
> Here's how a World-builder might use such a system in english:
>
> Give me a a highly realistic 10 meter long, 20cm wide, 10cm tall, 5mm
> thick steel I beam and a 2x4
>
That's english? I don't think that it is any easier to type than
the geometry!
KEvin