The first model looked convincing and was wrong by about forty meters. The station sat under the right avenue at roughly the right depth, but when I laid a street map over it, the entrances landed on the wrong blocks. The mesh was fine. The reference frame was not. That is the step map-to-3D work tends to skip. A generated scene can look correct alone and still be useless for measurement, sections, or overlays. Before adding an escalator, I had to decide where the model was, what zero meant, an...