Today I tried to improve Exotherm's strength by adjusting the evaluation function. First I made pawns increase in value as the amount of material on the board decreases; this way Exotherm should be more inclined to sacrifice a minor piece to help promote. (My first attempt at the math made the value boost way too big in some cases, ironically causing the bot to avoid promotion because the resulting queen was valued less than the pawn.) This turned out to be a smaller strength improvement than I expected, but maybe there's still tweaking to do.
I also changed the threat part of the evaluation function to highly value queens next to the opposing king because that arrangement nearly always leads to checkmate. Ideally that case would be handled by the normal tree search, but sometimes the checkmate is just over the edge of what the bot can see in time, so this pushes the bot towards the mate even if it doesn't yet know for sure that the game is over.
No comments:
Post a Comment