Some things Andy learned about how to make 2D shapes that collide and bounce off each other in the Godot 3 game engine, which makes it pretty easy to get a game up-and-running.
More info: http://www.artificialworlds.net/blog/2018/11/06/godot-2d-shapes-bouncing-off-each-other-video/
Godot version: v3.0.6.stable.official.8314054