ylva.c

A simple chess engine in C.

This is a rewrite of an older version that was in C++. A few features are missing and some stuff needs to be fixed as shown in Todos. These will be worked on subject to time constraints.

Supported UCI commands

• go : wtime, btime, winc, binc, movestogo, movetime, depth
• position: fen, startpos
• uci
• isready

Other commands

• perft n will count leaf nodes at depth n

Todos

• Complete writing move ordering
• Taper PSQT evaluation
• Add PSQT evaluation

Acknowledgements

• Richard Allbert's explanation of principle variation in his Vice series
• Marcel Vanthoor's Rustic chess engine for move ordering and PSQT explanation. I created my PSQT tables using a combination of Rustic's and these psqt tables.
• The Weiss engine, from which I got the idea to hash the first token of each uci command
• Chess Programming Wiki
• Oliver Brausch's Olithink, specifically his method for peeking std input to check for "stop" command interrupting engine search
• Analog Hors' explanation of magic bitboards
• Tord Romstard's source code for finding magic numbers
• Sebastian Lague's video, which was also the original inspiration for Ylva.

License

MIT