I'm the author of Castle Game Engine. It's a cross-platform 3D and 2D game engine using modern Object Pascal.
It is packaged in Debian (at version 6.4, last stable, now).
We're working intensively now on CGE version 7.0 with lots of new features, like visual editor, full glTF support, Physically-Based Rendering. You can download the snapshot CGE version 6.5 from our main page to see what's coming.
Along with the engine, we also made a view3dscene, a tool to view 3D models in various formats which is also packaged in Debian.
I'm also the maintainer of PasDoc, Pascal documentation generator (also packaged in Debian ).
Contact: you can reach me through email or Keybase (see here), or reach me via Castle Game Engine forum or chat, or reach me via pkg-pascal-devel mailing list.