shithub: moonfish

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fix PST evaluation and search

--- a/chess.c

+++ b/chess.c

@@ -284,6 +284,8 @@

 	type = (piece & 0xF) - 1;

 	color = (piece >> 4) - 1;

+	if (color == 0) y = 7 - y;

+	

 	if (x < 4) x = 4 - x;

 	else x %= 4;

--- a/search.c

+++ b/search.c

@@ -24,14 +24,12 @@

 	if (depth <= 0)

 	{

-		if (depth <= -4)

-		{

-			if (chess->white) return chess->score;

-			else return -chess->score;

-		}

+		score = chess->score;

+		if (!chess->white) score *= -1;

+		if (depth <= -4) return score;

 		if (chess->score >= beta) return beta;

-		if (chess->score > alpha) alpha = chess->score;

+		if (chess->score > alpha) alpha = score;

 	}

 	for (y = 0 ; y < 8 ; y++)

-- 

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