Add blocked pieces penalty

ArcticXWolf · Feb 27, 2021 · 09e64ff · 09e64ff
1 parent 7eec7f5
commit 09e64ff
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diff --git a/engines/axwchessbot/evaluation.py b/engines/axwchessbot/evaluation.py
@@ -23,6 +23,8 @@ def evaluate(self) -> int:
         score = int(self.evaluate_material_score())
         score += self.evaluate_pair_bonus()
         score += self.evaluate_tempo()
+        score += self.evaluate_blocked_pieces(chess.WHITE)
+        score += self.evaluate_blocked_pieces(chess.BLACK)
 
         if self.board.turn:
             # evals are from whites perspective, convert to current perspective
@@ -234,6 +236,33 @@ def evaluate_king_shield(self, color: chess.Color):
             return -score
         return score
 
+    def evaluate_blocked_pieces(self, color: chess.Color):
+        score = 0
+
+        # king blocks rook
+        side_rank = 0 if color == chess.WHITE else 7
+        if (
+            self.board.piece_type_at(chess.square(5, side_rank)) == chess.KING
+            or self.board.piece_type_at(chess.square(6, side_rank)) == chess.KING
+        ) and (
+            self.board.piece_type_at(chess.square(6, side_rank)) == chess.ROOK
+            or self.board.piece_type_at(chess.square(7, side_rank)) == chess.ROOK
+        ):
+            score -= score_tables.additional_modifiers["king_blocks_rook_penalty"]
+
+        if (
+            self.board.piece_type_at(chess.square(1, side_rank)) == chess.KING
+            or self.board.piece_type_at(chess.square(2, side_rank)) == chess.KING
+        ) and (
+            self.board.piece_type_at(chess.square(0, side_rank)) == chess.ROOK
+            or self.board.piece_type_at(chess.square(1, side_rank)) == chess.ROOK
+        ):
+            score -= score_tables.additional_modifiers["king_blocks_rook_penalty"]
+
+        if color == chess.BLACK:
+            return -score
+        return score
+
     def attacked_by_inferior_piece(
         self, move: chess.Move, evaluate_to_square: bool
     ) -> bool:

diff --git a/engines/axwchessbot/score_tables.py b/engines/axwchessbot/score_tables.py
@@ -18,7 +18,7 @@
     "tempo": 10,
     "king_shield_rank_2": 10,
     "king_shield_rank_3": 5,
-    "king_no_shield_penalty": 10,
+    "king_blocks_rook_penalty": 24
 }
 
 additional_settings = {