Próspero, Manuel JoãoPereira, Paulo JorgeMadalena Quirino2023-03-092023-03-092023978-3-03868-204-2https://doi.org/10.2312/pt.19881536https://diglib.eg.org:443/handle/10.2312/pt19881536A hierarchical graphical modelling system and a dialogue centrei mechanism were designed and implemented in first order predicate logic. Some main concepts are introduced in this papar by analysing a given application: a flat drawing design where the user is able to graphically specify the intended configuration and get important information about the existing restrictions.Attribution 4.0 International License10.2312/pt.19881536