The Sims 1, 2 or 3 were made for people who want to control people or for people who want to create works of art. Don't quote me on this but I remember a Will Wright video where he said people enjoyed building in the game things more than actually controlling the sims.
I've never had any interest in the Sims, so I guess I've deprived myself of a fairly powerful in-game content building system. I just watched some examples of user created houses for The Sims 3 on YouTube. I'm impressed with the granularity of the game's system though this approach would be too time-consuming for building customized cities. For my project I'm approaching a similar level of granularity, though it's compartmentalized. Essentially players could create content modules at a micro granularity level (similar to Sims 3) that could then be plugged into customized buildings, superstructures, or archologies.
I'd be curious about any other examples as well. I've been developing a proof of concept for a planetary exploration and colonization game that contains infrastructure and city development at its core. I actually already have a prototype for an in-game content creation system (focussed on terrain and structures) but would be interested in seeing other approaches.
My city building process is a hybrid combination of simulation and customized world crafting on part of the player.
In the title you mention modification of existing buildings. So is the city building aspect purely simulation then with the player customizing each building after it's generated?
Krohm, I guess it's the periodic "resetting" of the coordinate system that I'd be interested in learning more about. Are there currently any engines or good examples where this technique is employed?
I could imagine that there may be camera and geometry jittering or jumping at the point where the coordinates are reset if the precision of the translation isn't exact. Or equally problematic I suspect there might be a performance hit depending on the frequency that this "reset" occurs and the number and complexity of elements that have to be "resetted."
Also, does anyone know of the official terminology that should be used when referring to a localized coordinate system such as the concept described above? I never get the results I would expect when looking for localized coordinates systems in search engines, even within the context of games.