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Pac-Man ghost AI question

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Greetings!

 

I am pleased to announce that version 1.0 of The Pac-Man Dossier is now available here:

 

http://home.comcast.net/~jpittman2/ThePacManDossier.pdf

 

 

Changes from earlier versions include:

 

- Most importantly, Chapters 3 & 4 have been entirely rewritten to accurately reflect new discoveries on how the ghost logic code actually works (much thanks to Don Hodges).

 

- The game's tile system is discussed in detail.

 

- The split-screen bug is described correctly.

 

- Much of the overall text has been updated for better clarity.

 

 

The guide will continue to be available at the same web address for the forseeable future, and will be updated as the need arises.

 

Happy New Year,

 

Jamey Pittman

[email protected]

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Here's a good mystery. Check out this .inp file (MAME 0.128) of me screwing around and just observing behavior. Specifically, notice what happens on the strawberry level after I eat the first energizer - 3 of the ghosts get "stuck" in the monster pen for quite some time! I've never noticed this before but find it quite interesting. Anyone know why this happens?

 

http://home.comcast.net/~jpittman2/pacman.inp

 

-Jamey

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Like the guide by the way. I'm just curious though. I've never seen any examples of why or what circumstances causes the ghosts to use the tunnels..

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Like the guide by the way. I'm just curious though. I've never seen any examples of why or what circumstances causes the ghosts to use the tunnels..

 

Thanks, Shannon. The ghosts have no concept of the side tunnel, really; they are simply making the best turn they can to reach a target tile at an intersection (in this case, one of the two intersections that include a side-tunnel entrance). Sometimes Pac-Man is positioned/oriented in such a way that a ghost's target is closest to side tunnel turn - that's all. See Chapters 3 & 4 for more info. Hope this helps!

 

-Jamey

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I've never seen any examples of why or what circumstances causes the ghosts to use the tunnels..

 

Let me also give a visual example which may help:

 

PinkyTunnel.jpg

 

Pinky's target is 4 tiles up and left of Pac-Man when Pac-Man is facing up. This puts his target tile inside the left tunnel in this example, which is why he turns towards it.

 

-Jamey

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New version of the guide is up: http://home.comcast.net/~jpittman2/ThePacManDossier.pdf

 

I added a section on the ghost house (pgs. 12 & 13) that covers everything I found out including how to keep the ghosts trapped inside for as long as possible via a flaw in the logic.

 

Probably because there is so much involved with the different controls, this section was not easy to write, so let me know if something doesn't make sense.

 

-Jamey

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Forgot to ask. Couldn't remember if it was in the doc and maybe I just overlooked it.

 

But the original version of pacman had to be changed because it was too easy to use patterns. I used to know the patterns for the older one. But they changed it so those patterns didn't work. Of course the good players just came up with a set of patterns.

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Forgot to ask. Couldn't remember if it was in the doc and maybe I just overlooked it.

 

But the original version of pacman had to be changed because it was too easy to use patterns. I used to know the patterns for the older one. But they changed it so those patterns didn't work. Of course the good players just came up with a set of patterns.

 

The second table in Appendix A shows how the levels are reordered via a difficulty jumper that is normally disconnected on the PCB. Once players figured this out, several bootleg modification packages for Pac-Man became popular with arcade operators. Bally Midway objected strenuously to the operators use of these unauthorized modification boards and eventually released Pac-Man Plus as a legitimate upgrade kit for Pac-Man.

Edited by jpittman

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I finally figured out enough HTML to get the Pac-Man Dossier moved over to a web page: http://home.comcast.net/~jpittman2/pacman/pacmandossier.html. Same text as the most recent .PDF, but with a table of contents and a ton of hyperlinks to make navigating the document very easy. This will remain its address from now on and all further revisions will be to the web page and not the .PDF. As usual, please advise if you find any mistakes.

 

-Jamey

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I added .PDF scans for two Pac-Man guides from the 1980s:

 

- How To Win At Pac-Man, by Penguin Books

- Break A Million At Pac-Man, by Ernest Zavisca, Ph.D. and Gary Beltowski

 

They are in Appendix D on the site: http://home.comcast.net/~jpittman2/pacman/pacmandossier.html.

 

-Jamey

This is very cool; thanks for putting this all together.

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I added .PDF scans for two Pac-Man guides from the 1980s:

 

- How To Win At Pac-Man, by Penguin Books

- Break A Million At Pac-Man, by Ernest Zavisca, Ph.D. and Gary Beltowski

 

They are in Appendix D on the site: http://home.comcast.net/~jpittman2/pacman/pacmandossier.html.

 

-Jamey

This is very cool; thanks for putting this all together.

 

It was my pleasure, really. I always wanted a "comprehensive" Pac-Man resource that was highly detailed and accurate as to the ghost A.I and pathfinding abilities. It's grown a bit larger in size and scope than I had initially planned, but it's turning into a fairly decent web page that I'm glad to make available to everyone. :)

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