neongreen / ches Goto Github PK

Apparently I forgot to use it

Would allow us to implement things like

• Chess, but Edward switches sides. Your opponent's Edward is indestructible and is given way to promotion. The game continues on otherwise.

• Chess, but the enemy queen is an evil witch. She has cast a curse upon your army! While the enemy queen is still alive, only pawns and bishops can move. Defeating her frees the other pieces from their immobility. // (unclear if a newly promoted queen should have the witch power, but can playtest both)

A meta-leaderboard

Sad

Ideally actually require to press 'reset' first (easier than doing a popup?)

See golden-games.ts. For whatever reason the generated games are slightly different compared to just always using 'search.findBestMove'.

I spent an hour (?) investigating and I have no idea why. It'd be nice to walk through 'findBestMove' with the debugger. Maybe it's due to the transposition table?

Update: possibly because when we reach depth=0 in the search, we don't actually detect draws/checkmate, we just use leaf eval - but evaluateBoard does do detection at depth=0, which is an inconsistency.

Update 2: I tried changing evaluateBoard to use leaf eval, but it just got worse.

Requested by Mendax on Discord

golden-games/1515dfc7-4ed7-444d-a8cb-ac6b35e699bd/depth-4.txt

1. a4 -0.18
... Nc6 +0.02
2. c3 -0.19
... Na5 +0.21
3. d3 -0.18
... e6 +0.22
4. b4 -0.34
... Nc6 +0.86
5. b5 -0.33
... Na5 +0.86
6. e4 -1.14
... a6 +0.07
7. bxa6 -0.35
... Rxa6 +0.85
8. d4 -1.16
... Rb6 +0.86

But the game plays Rc6.

https://www.chessprogramming.org/Check

Currently a lot of time is spent on isInCheck

See https://github.com/esbuild-kit/tsx and privatenumber/tsx#343.

Would also allow us to switch from process.cwd() back to __dirpath I guess. And get rid of $FILE. And "tsx" is just a cool name. Although "esbuild" is also a cool name tbh.

Should speed up the engine.

https://www.chessprogramming.org/Incremental_Updates

https://www.chessprogramming.org/Unmake_Move

• Board.unmakeMove()
• Node.unmakeMove()
• assertions in bench
• switch Search to use unmakeMove()

golden-games/1515dfc7-4ed7-444d-a8cb-ac6b35e699bd/depth-4.txt:

19. Ke1 -8.91
... Qf2 -7.11
20. Kd2 -7.11
... Qe3 -7.11
21. Ke1 -7.11
... Qf2 -7.11
22. Kd2 0.00
1/2-1/2 0.00

Black is unencumbered here. Why does he make a move that allows a draw? Alternatively, why is eval for 21... determined to be -7.11? At depth=4 it should see that white can draw on the next move.

I want screenshots from Ches to be recognizable

Why

In progress

• go through discord challenges
• go through chess simp challenges
• _2022_03_07
• _2022_05_30
• _2021_08_17

Would be kinda neat to be able to send someone a challenge with a specific depth, material values, piece-square bonuses, etc

Games for "play on the same file" surprisingly end in a draw even at depth 4. I'd like to see PGNs for them so that I can follow them in a chess GUI.

This would require a) export to PNG and b) freezing the engine

Partly for the purpose of move-number-based-challenges.

Would let us easily implement things like:

• https://discord.com/channels/866701779155419206/884667730891010048/1122440838719479808 -- "Chess, but all of your pieces (and pawns) are vampires. Anytime one of your pieces (or pawns) has a direct line of sight past your opponent’s edge of the board, they are hit by sunlight and turn to ash."

• Andrey's challenge (every two moves you unlock a new piece and you can only use previously unlocked pieces)

• Chess, but your first piece (or pawn) moved cannot die, your second piece (or pawn) moved is your only piece (or pawn) that can capture pieces, and your third piece (or pawn) moved must deliver the checkmate. (also needs #7)