Tune eval parameters

mhonert · Jul 25, 2020 · b1ce305 · b1ce305
1 parent 46e5eb4
commit b1ce305
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Showing 12 changed files with 914 additions and 277 deletions.
diff --git a/.gitignore b/.gitignore
@@ -36,3 +36,6 @@ public/as-api.wasm.map
 
 # PGN files
 **/pgn/*
+
+# FEN files
+**/fen/*
diff --git a/README.md b/README.md
@@ -55,3 +55,4 @@ This project is licensed under the GNU General Public License - see the [LICENSE
 ### Attributions
 * Images for the chess pieces come from [Wikimedia Commons](https://commons.wikimedia.org/wiki/Category:SVG_chess_pieces)
 * The opening book was generated from a selection of chess games from the [FICS Games Database](https://www.ficsgames.org)
+* A set of 725000 [test positions](https://bitbucket.org/zurichess/tuner/downloads/) collected by the author of Zurichess was used to tune all evaluation parameters 
diff --git a/artifacts/release_notes.md b/artifacts/release_notes.md
@@ -1,15 +1,14 @@
 
-This release contains many small improvements, but the largest ELO gain came from the new mobility evaluation :cartwheeling:
+This release focussed on tuning the evaluation function :balance_scale:
 > The Web App version of **Wasabi Chess** can be played [**here**](https://mhonert.github.io/chess).
 
 ## Changes
-- Add mobility evaluation
-- UCI: output mate distance as score when a mate was found
-- Evaluation: provide bonus for pawns covering pawns and knights
-- Adjust piece and move ordering values
-- Slightly increase LMR threshold
-- Simplify and tune futility margin calculation
-- Directly jump to quiescence search for futile positions at depth 1
+- New tuning tool
+- Tuned all evaluation parameters
+- Replaced simple mobility score calculation with mobility score table
+- Replaced simple king safety calculation with king threat score table
+- Improved game phase calculation for tapered eval
+- Added endgame piece square tables 
 
 ## Installation
 - Download and unpack the archive for your platform (Linux or Windows 8/10)

diff --git a/assembly/__tests__/board.spec.ts b/assembly/__tests__/board.spec.ts
@@ -605,7 +605,7 @@ describe('King threats', () => {
     const board: Board = fromFEN("2kr4/ppp5/2n5/5p2/1Pb1P3/P4P2/1BP1RKrq/R7 w - - 0 28")
 
     board.getMaterialScore()
-    expect(board.getMaterialScore() - board.getScore()).toBeGreaterThan(90, "King threat penalty is not high enough")
+    expect(board.getMaterialScore() - board.getScore()).toBeGreaterThan(70, "King threat penalty is not high enough")
   });
 });
 

diff --git a/assembly/__tests__/engine.spec.ts b/assembly/__tests__/engine.spec.ts
@@ -198,9 +198,9 @@ describe('Finds moves', () => {
     ]);
     board.increaseHalfMoveCount();
 
-    board.performEncodedMove(findBestMoveIncrementally(board, BLACK, 11, 0));
-    board.performEncodedMove(findBestMoveIncrementally(board, WHITE, 3, 0));
-    board.performEncodedMove(findBestMoveIncrementally(board, BLACK, 5, 0));
+    board.performEncodedMove(findBestMoveIncrementally(board, BLACK, 13, 0));
+    board.performEncodedMove(findBestMoveIncrementally(board, WHITE, 5, 0));
+    board.performEncodedMove(findBestMoveIncrementally(board, BLACK, 9, 0));
     board.performEncodedMove(findBestMoveIncrementally(board, WHITE, 3, 0));
     board.performEncodedMove(findBestMoveIncrementally(board, BLACK, 1, 0));
 

diff --git a/assembly/bitboard.ts b/assembly/bitboard.ts
@@ -31,7 +31,7 @@ export const BLACK_QUEEN_SIDE_CASTLING_BIT_PATTERN: u64 = 0b00000000_00000000_00
 export const LIGHT_COLORED_FIELD_PATTERN: u64 = 0b01010101_01010101_01010101_01010101_01010101_01010101_01010101_01010101;
 export const DARK_COLORED_FIELD_PATTERN: u64 = 0b10101010_10101010_10101010_10101010_10101010_10101010_10101010_10101010;
 
-const KING_DANGER_ZONE_SIZE: i32 = 3;
+export const KING_DANGER_ZONE_SIZE: i32 = 2;
 
 function isBorder(boardPos: i32): bool {
   if (boardPos < 21 || boardPos > 98) {