Improve Draw Detection (#71)

xu-shawn · web-flow · commit 14f9f5bc843f · 2024-05-30T13:22:09.000-07:00
Elo | 0.32 +- 2.58 (95%) SPRT | 8.0+0.08s Threads=1 Hash=8MB LLR | 2.98 (-3.86, 2.98) [-4.00, 1.00] Games | N: 35484 W: 9103 L: 9070 D: 17311 Penta | [610, 4149, 8171, 4222, 590] https://chess.aronpetkovski.com/test/242/ bench 977698
diff --git a/Serendipity/src/main/java/org/shawn/games/Serendipity/AlphaBeta.java b/Serendipity/src/main/java/org/shawn/games/Serendipity/AlphaBeta.java
@@ -279,7 +279,7 @@ private int mainSearch(Board board, int depth, int alpha, int beta, int ply, boo
 			throw new TimeOutException();
 		}
 
-		if ((board.isRepetition(2) && ply > 0) || board.isRepetition(3) || board.getHalfMoveCounter() > 100)
+		if (ply > 0 && (board.isRepetition(2) || board.getHalfMoveCounter() > 100 || board.isInsufficientMaterial()))
 		{
 			return DRAW_EVAL;
 		}

Original file line number	Diff line number	Diff line change
`@@ -279,7 +279,7 @@ private int mainSearch(Board board, int depth, int alpha, int beta, int ply, boo`
`279`	`279`	`throw new TimeOutException();`
`280`	`280`	`}`
`281`	`281`
`282`		`- if ((board.isRepetition(2) && ply > 0) \|\| board.isRepetition(3) \|\| board.getHalfMoveCounter() > 100)`
	`282`	`+ if (ply > 0 && (board.isRepetition(2) \|\| board.getHalfMoveCounter() > 100 \|\| board.isInsufficientMaterial()))`
`283`	`283`	`{`
`284`	`284`	`return DRAW_EVAL;`
`285`	`285`	`}`