There is an example showcase game, I presented at HAL 2016. This is a kind of 3D space invaders game. The slides HAL explain how it has been programmed and also, they show some background ideas behind HGamer3D.

You can run the game directly on all three platforms (Linux, Windows, Mac) by issuing the command: aio

Also, there is a sample browser available, which you can run by either: aio SampleBrowser. (You need to have the alias set, see last section on tooling).