Pac-Man: Ghost AI & Behavior Modes

[@BiffsGamingVideos]

I included the beginning at the last minute briefly going over ghost AI. The nitty gritty is the modes and how long they stay on for each level.

[@2kBofFun]

Nice compact explanation. It has an ommishion in the Inky target tile explanation. That one is not between pink and red. It does calculate that target title, but it ads the distance vector of the current position of blinky towards that target tile. The result is that Inky and Blinky usually come into you from 2 sides, and that pinky tries to be ahead of you.

[@BiffsGamingVideos]

This was simplified. The pac-man dossier gives a more detailed explanation. pacman.holenet.info/

[@sagantruong8961]

Blinky’s (Red Ghost) target tile is where Pac-Man is. Pinky’s (Pink Ghost) target tile is 4 tiles in front of Pac-Man, but if Pac-Man is facing up, then Pinky’s target tile is 4 tiles up and left. Inky’s (Cyan Ghost) target tile is 2 tiles in front of Pac-Man but just like Pinky, if Pac-Man is facing up, it’s 2 up and left. Then, Inky finds the length between the first target and Blinky and rotates it 180°, and at the end of it is Inky’s target tile. Clyde’s (Orange Ghost) target tile is where Pac-Man is just like Blinky but only if Clyde is more tiles then an 8 tile radius away from Pac-Man. if not (less tiles then an 8 tile radius away from Pac-Man), then he moves out of the radius and tries to go to the bottom-left corner.

[@bleirdo_dude]

If I was the programmer I would have put in a "I have to take a dump" mode. This is where the ghosts have to go, and the home is seen as a porta potty, but the "Occupied" display is seen by the ghosts. They do the seek mode around the ghost home.

[@BiffsGamingVideos]

Or maybe instead of calling a game "Q*bert" you would just call it "snots and buggers"..... (Seriously)

[@bleirdo_dude]

@@BiffsGamingVideos I'm talking about behind the scene programming, not marketing.

[@BiffsGamingVideos]

@@bleirdo_dude store.steampowered.com/app/577080/A_Dump_in_the_Dark/

[@bleirdo_dude]

@@BiffsGamingVideos HA!

[@2kBofFun]

I just made my own pac-man, and by accident it has your desired poop mode. You can enter the ghost house, but the ghosts can't go in if they are chase or scatter.

[@TheBigBentley911]

Fascinating video, man! Very cool. I always wondered how the AI operated in Pac-Man.

[@BiffsGamingVideos]

The video was not about AI, but the behavior modes. The AI was a last-minute thing. I didn't want to spend too much time on it. For example, 1 ghost's target changes when looking up. If you really want detail, then check out the Pac-Man Dossier: www.gamasutra.com/view/feature/3938/the_pacman_dossier.php?print=1

[@Johan-rm6ec]

Inky eventually get's you at the bottom save spot.

[@BiffsGamingVideos]

what do you mean?

[@dilanalpay3488]

I'm working on a pacman clone in Unity (C#) and this video has been very helpful. The one thing I don't seem to be able to find anywhere online is what determines when the ghosts leave the house. They seem to leave at different times when you die and reset the level, and it seems to maybe be overriden based on a number of dots collected, but I can't figure out the formula being used here. Have you covered that topic in one of your many videos? If not, do you know the answer?

[@BiffsGamingVideos]

pac-man dossier has it i think. I know I read it somewhere. There is an order to who exists when. I has to do with the number of dots eaten and a timer. This also allows a trick to trapping a ghost inside the house (I have a video on that). If not on the dossier, then something from don hodges (bottom of the page). I don't have the time right now to look it up, but I have seem detailed explanations. You can also try just looking at the code yourself. I have modified it myself. it's in assembly. pacman.holenet.info/ donhodges.com/how_high_can_you_get2.htm Here is ms. pac-man code so a lot is exactly the same as pac-man github.com/BleuLlama/GameDocs/blob/master/disassemble/mspac.asm

[@BiffsGamingVideos]

Heres the pac-man Z80 code www.cubeman.org/arcade-source/pacman.asm

[@kilroy987]

I've been working on my own Pac-Man app, trying to get the arcade patterns working on it. The big problem I've run into is that the ghost's movement amount each frame is determined by a 16-element cycling set of numbers that tell them to travel either 0, 1 or 2 pixels on a given frame. But when a power pellet is eaten, or they enter a tunnel and leave, the current move index changes in an undefined way. Additionally, sometimes, when they reverse direction, they'll follow a completely different sequence of move amounts for a little while then return to the original set (for instance, the move pattern might be 1111211112111121, but after eating a power pellet it might be 0111111111112111 for one cycle, or some weird thing). There are too many unknowns preventing me from making the animations pixel perfect so that arcade patterns work. If I can ever figure that out, I'll revisit it. But in the meantime, I'm just finishing up the rest and living with it.

[@SuperGibaLogan]

this looks like something made in 2012