The Electro Gyrocator essentially worked that way. You placed transparencies over the CRT for the map section you were currently in. https://en.wikipedia.org/w

The Electro Gyrocator essentially worked that way. You placed transparencies over the CRT for the map section you were currently in. https://en.wikipedia.org/wiki/Electro_Gyrocator https://en.wikipedia.org/wiki/Electro_Gyrocator https://www.pistonheads.com/news/ph-features/ph-origins-navigation-systems/37314 https://www.pistonheads.com/news/ph-features/ph-origins-navi...