I have started playing with outer city buidongs by dusting off Greeble in max. I first cut the strets out using procutter setting the remaining slices to be quad meshed. This gives you nice quads running parallel to the streets. I them Greebled it all and set each "building" a unique material ID by script. I clipped about 20 or so building tops and sides from a photgraph and mapped them onto the random ID'ed boxes. It needs work but I think it has promise.
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