Thanks for posting.  This is very interesting to me.  I used to do pen and pencil drafting back in the 70's designing cast in place concrete formwork.  I worked on the forms used to cast the EPCOT Center and monorail at Disney World, but most of my projects were alot less interesting.  Things like highway bridges, turbine pedestals, and fish ladders.  My computer at the time was a .... oh,  wait a minute,  there were no computers at that time.  :lol:
     Feel free to post some more real world 3d applications.  I am very interested in how you get real world elevation data into a 3d application.  I use Rhinoceros and Bryce.

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