Thanks guys,

Hi chipp,

Well that's some really nice results, actually I haven't think about playing with transparency alpha's (I will probably use clip map to speed up the raytracing).

As for the rules, originally building where indeed using a slope angle rule, but I change my mind after few population test and decide to give the exact areas 'by hand', by isolating some poly's.
There is only 'one' type of building, but off course the floors numbers and windows position are based on their height. Finding a good balance between chaos and structure is really tricky.
(I still have many stuff to learn in that area :)).