https://discourse.threejs.org/t/collisions-two-objects/4125/2
https://hofk.de/main/threejs/kollision/02_kollision.html
https://discourse.threejs.org/t/solved-geometry-vertices-is-undefined/3133
"l" turn left ... "r" turn right ... "w" ahead ... "a" left ... "d" right ... "s" back ... "h" higher ... "t" lower