Hello. We create the 3D models using photogrammetry from aerial imagery. You can read more about AccuCitis technology at www.accucities.com/x-y-z-mapping-of-cities-by-accucities/
Depends on what you want to do within Substance Painter, but yes, the 3D models can be taken into SP and adjusted there. The FBX files have the UVs unwrapped (which is what Substance requires) so you can use the software with our models just like you would use it with any other 3D asset. BTW, if you need an FBX version of the 3D London sample, you can download it here: we.tl/t-JogLnc5LA8
The Textured model is in FBX format in 4 x 500x500 meters tiles. These vary in size: 700, 800, 1500 and 1900 MB respectively. You can download them here: we.tl/t-JogLnc5LA8
Yes, by all means, these are all native functionalities in those game engines. Check out the functionalities we have managed to get out of UE4 for urban planning here (video): ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-OPa9LfE7y84.html
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