tunnel
A ship down an endless tunnel, shooting waves of enemies under three colored lights.
Controls
The directional buttons and L1 and L2 move the ship, R1 fires, Select makes moves faster, Select and L2 step slowly, Start pauses, and Start and Select together quit.
A port of L. Evans's Net Yaroze game demo "tunnel" (Sony, 1997), the last of the tutorial series it was built up over: a ship flying down an endless tunnel, shooting waves of enemies. The tunnel is rings of four scaled squares that slide towards the ship and go round to the far end again; the near ones are subdivided so the perspective holds up. Fog, three colored lights, one of them always circling, and semi-transparent sprites for shots, explosions and pick-ups make it the most of the machine's lighting any of the examples use. Its sound is a VAB: a tune started once and left playing, and sound effects keyed on and off by hand. The score is drawn in sprites cut from a font texture.
Enemies come in waves: helixes of fighters circling as they come, some switching direction or darting as one, lone attackers that jiggle, evade or circle while they fire, swarms of insect ships, and every so often a robot. Pick-ups give a life, faster shots or movement, or set the lights or the view swinging. The game gets faster every thousand frames.
Differences from the original:
- The data is read off the disc to the addresses the original's batch script sent it to.
- The random numbers are seeded with a constant. The original seeds them from the seconds of the time it was compiled.
- Quitting returns to the BIOS. The original first saves the screen to RAM for the serial console to fetch, and calls exit.
- The direction a shot is fired in is normalised in integers, exactly; the original uses floating point.
- What the original prints to the serial console is left out, and so are its assertions.