Hi, KOSMIndoorMap is a QML component for showing multi-floor OSM indoor maps (as its very creative name might suggest). It's using maps.kde.org as a data source (same as Marble), and has been created to show interactive maps of train stations for KDE Itinerary.
https://invent.kde.org/libraries/kosmindoormap KOSMIndoorMap has been growing inside the KPublicTransport repo (due to some building blocks being available there alreay and me being lazy), and has now been split into its own repo. So technically this is coming out of a reviewed repo already rather than from playground, but better be on the safe side :) The aim is having this (together with KPublicTransport and KDE Itinerary) join the release service for 20.12. Thanks, Volker