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I need to know what is the maximum size you can create for a realistic city


I think 50000 quants in all directions (-x,+x,-y,+y,-z,+z)
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Can the whole city be seen at the same time in the WED if zoomed out?


Adjust the view depth with + or - on your keyboard (for every view of WED)
As for a huge city where every building can be entered with details of course maby the machine that can pass that limit is somewhere in NASA

Extensive Multiplayer tutorial:
http://mesetts.com/index.php?page=201