“…Similar to other skeletal structures [13], it is also possible to derive three-dimensional terrains from a VRS that can be used as intricate roofs over polygonal footprints of buildings. For a polygonal footprint P , a point p of Computer-Aided Design & Applications, 18(5), 2021, 875-889 © 2021 CAD Solutions, LLC, http://www.cad-journal.net S w (P ), with coordinates (p x , p y ), is lifted to a point in R 3 with coordinates (p x , p y , d w (p, s)).…”