simple ai

Merry Christmas! Today is the last day for my 2016 advent calendar.

I admit it ends on a bit of wimper, some of the earlier entries were much more interesting. Probably the most entertaining entry was the first, hockeyclaus. It's based on santaskate, which is the very first one I made when I started constructing these in 2009. It's an easy enough game, but not quite trivial, and some people say they just like bully bashing the elves around.

I used a crude heuristic to give the elves some smarts.... essentially I draw a line between the puck and the goal, and then a circle a small, arbitrary distance around the puck. If the puck is further from the goal than the elf is, the elf tries to get to the intersection of that line and circle but on the far side of puck - if the puck is nearer the goal, the elf tries to drive through the puck to the goal, that's the point it's attracted to.

I added a debug feature to the game, hit 'd' to toggle the extra visualization:

In this diagram, you see the lower elf is nearer the goal than the puck is, so is attracted to a point behind the puck, while the upper elf figures it's more or less on the other side of the puck already. Clearly not a good algorithm, but I'm ok with this game not being very challenging.

It might be cool to make this a Comp Sci programming challenge... how would two teams of one or two elves compete, in what is roughly a full-round-arena version of air hockey? I could see making an interface that both fully describes the "world" and all actors in it, and then lets the program say what direction of thrust each player it controls gets... I wonder what strategies would emerge from people who are actually good at programming AI.