Retrochallenge Update: Hacman Moves!Posted: July 23, 2012
This is a delayed update, but I finally have first motion in my game. I’ve been recreating a Pac-Man clone I first wrote as a high-school student for a text-mode terminal on our school’s PDP-11/60 running RSTS/E.
I’ll provide another update with more technical details, but this is great progress. The only major parts of the game I need to finish are the ghost AI routines and the sprite collision routines; the latter routines are almost trivial, so that leaves the AI. This will either be doable—or not—and I am thinking it’s doable, so I expect that when the Retrochallenge ends for July, I will have a working game!
In my game, presently, I can move the Hac-Man character. It eats dots and pills, and the ghosts, while not moving, do change appearance, and change back. Hac-Man can use the tunnel. Points add up and the game logic correctly recognizes each level’s completeness. I only need to add a fruit—my original game had two different fruits. The levels top out at 255, in a homage to the original game (though it does not crash as the original game did.)
I deviated from history just a bit in the design of the maze: The original game worked on a VT-52, and an ADDS terminal (the model number of which I do not remember and which is not on Bitsavers either). Neither of them had line-drawing characters, only blocks (of a sort) that, as one commenter put it, made the game look more like the old Unix text classic Dungeon, rather than the casual maze of Pac-Man, and my clone.
Salem High just missed the VT-100 by that much, having gotten our system circa 1976; the VT-100 was already available by the time I wrote my game in 1980. I think its new appearance is worth any historical infidelity it may cause, since my program logic hasn’t changed any. If there is still a PDP-11 running RSTS/E somewhere, it can run my game as long as it talks to a VT-100 or compatible.
Technical details will follow in my next post, and expect more frequent updates as I have more time to work on the game and explain even more of the details.
Wakka wakka wakka!