Skip to main content

Perft to find bugs in move generation

22 Jun 2022

after 2 am

  • almost completed legal move generation function
  • issue: sometimes switches black and white during random play
  • issue: handling castling rights and enpassant squares while undoing a move

23 Jun 2022

after 12 am

  • bugfixsan notation doesn't show promotion
  • added perft and divide function
  • now we can find corner cases easily!

    2 am

  • wasted 1 hour on why I'm getting 1 move less than expected reason: code generates kingside else queenside castling moves 🥲

    3 am

  • bugfix: now engine checks threatened squares during castling
  • improved perft function
  • still a lot of things to do (getting wrong perft results)

Comments

Popular posts from this blog

Better algorithms and Evaluation function

  11 Oct 2022 long time no see 3 am well, there's a lot of small and big changes. i'll try to explain by checking the diff. AI part: replaced minimax with alpha-beta (similar to negamax version) TODO : implement quiescence search added piece-square table scoring in eval function reduced branching in code move generation part: bugfix : moves like  e1c1  were always interpreted as castling, fixed changed board representation from  string  to  char[64] now king positions are incrementally saved, so faster to find kings several optimizations in move generation general: now engine trys to avoid moves leading to repetitions (but it is not always optimal, so should do something better) fixed several gui bugs in promotion and flipping gui supports (some) premoves fixed some bugs in move hints, still some remaining ig faster makefile BIGGEST UPDATES: uci protocol working! made a  lichess bot  running this engine!

Making moves with the Negamax algorithm

  10 Sept 2022 after a loooonngg time!!! 4:50 am there's a lot to tell you, but firstly, i'm very happy now because i just teached my ai to capture pieces and guess what, it doesn't just look one move into the future. yes guys, i wrote the negamax algorithm!! it's much more fun to play with it now. but still it has to prioritize other things besides captures, like promotions, checks, pins etc. and obviously, mates! now i'm going to sleep as i got many works to do :(

Move generation

1 Jun 2022 after 12 am ditching color output for now reading evening, night more reading modularizing, exceptions 2 Jun 2022 after 12 am started writing this blog lol ### started writing move generation function