
Pac-Man / Galaga repro joystick to solve the 4-way problem. Dig Dug may illustrate your point better. The only way to stop Pac-Man is to hit a wall. He keeps moving forward when the joystick is in neutral position, and it's normal to make your turn inputs early. I don't think Pac-Man is the best example of this. "We don't want to leave them as neutral because then Pac-Man would stop dead in his tracks in between direction changes," These shorthand rules can be confusing, so I'll step through an example with the 8-way joystick. Repeated rows don't need to be specified.If a row has been shortened to 5 or fewer characters by rule #2, repeated values at the end of a row string don't need to be specified.The last four columns don't need to be specified if they're symmetric with the first four (left-right symmetry).The last four rows don't need to be specified if they're symmetric with the first four (i.e., up-down symmetry).These strings of characters can be a bit unwieldy, so MAME has a shorthand notation that uses the following rules: Putting all of this together, we can turn the joystick maps shown in the previous section into strings of numbers and letters:

The only other value we need to represent is the sticky, which is denoted with an "s".įinally, we distinguish individual rows of the 9x9 grid by separating them with a period.

Note that this is the same direction/number mapping that appears on the NumPad of a keyboard.
