Space Chase, one token at a time

An animated game for a calculator with one megahertz, 32 kilobytes, and a screen that is a string of 548 characters. Ten programs, no graphics library, no collision routine and no input handler — because the machine could be talked into doing all three by other means. Three passes through it: how a ship gets built, what happens in one frame, and how a ship moves.

The listing

The screen — 137 × 32

running
Space or → steps · Enter runs to the next note. Underlined tokens have something to say.

The stack

What is happening