Moved board evaluation logic to MoveProcessor

This commit is contained in:
Kai S. K. Engelbart 2019-10-30 17:11:57 +01:00
parent acf6bf36c1
commit 9aea4bd9d4
Signed by: kske
GPG Key ID: 8BEB13EC5DF7EF13
2 changed files with 73 additions and 70 deletions

View File

@ -26,40 +26,6 @@ public class Board {
private Map<Color, Position> kingPos = new HashMap<>(); private Map<Color, Position> kingPos = new HashMap<>();
private Log log = new Log(); private Log log = new Log();
private static final Map<Type, int[][]> positionScores;
static {
positionScores = new HashMap<>();
positionScores.put(Type.KING,
new int[][] { new int[] { -3, -4, -4, -5, -5, -4, -4, -3 }, new int[] { -3, -4, -4, -5, -4, -4, -4, -3 },
new int[] { -3, -4, -4, -5, -4, -4, -4, -3 }, new int[] { -3, -4, -4, -5, -4, -4, -4, -3 },
new int[] { -2, -3, -3, -2, -2, -2, -2, -1 }, new int[] { -1, -2, -2, -2, -2, -2, -2, -1 },
new int[] { 2, 2, 0, 0, 0, 0, 2, 2 }, new int[] { 2, 3, 1, 0, 0, 1, 3, 2 } });
positionScores.put(Type.QUEEN,
new int[][] { new int[] { -2, -1, -1, -1, -1, -1, -1, -2 }, new int[] { -1, 0, 0, 0, 0, 0, 0, -1 },
new int[] { -1, 0, 1, 1, 1, 1, 0, -1 }, new int[] { -1, 0, 1, 1, 1, 1, 0, -1 }, new int[] { 0, 0, 1, 1, 1, 1, 0, -1 },
new int[] { -1, 1, 1, 1, 1, 1, 0, -1 }, new int[] { -1, 0, 1, 0, 0, 0, 0, -1 },
new int[] { -2, -1, -1, -1, -1, -1, -1, -2 } });
positionScores.put(Type.ROOK,
new int[][] { new int[] { 0, 0, 0, 0, 0, 0, 0, 0 }, new int[] { 1, 1, 1, 1, 1, 1, 1, 1 }, new int[] { -1, 0, 0, 0, 0, 0, 0, -1 },
new int[] { -1, 0, 0, 0, 0, 0, 0, -1 }, new int[] { -1, 0, 0, 0, 0, 0, 0, -1 }, new int[] { -1, 0, 0, 0, 0, 0, 0, -1 },
new int[] { -1, 0, 0, 0, 0, 0, 0, -1 }, new int[] { 0, 0, 0, 1, 1, 0, 0, 0 } });
positionScores.put(Type.KNIGHT,
new int[][] { new int[] { -5, -4, -3, -3, -3, -3, -4, -5 }, new int[] { -4, -2, 0, 0, 0, 0, -2, -4 },
new int[] { -3, 0, 1, 2, 2, 1, 0, -3 }, new int[] { -3, 1, 2, 2, 2, 2, 1, -3 }, new int[] { -3, 0, 2, 2, 2, 2, 0, -1 },
new int[] { -3, 1, 1, 2, 2, 1, 1, -3 }, new int[] { -4, -2, 0, 1, 1, 0, -2, -4 },
new int[] { -5, -4, -3, -3, -3, -3, -4, -5 } });
positionScores.put(Type.BISHOP,
new int[][] { new int[] { -2, -1, -1, -1, -1, -1, -1, 2 }, new int[] { -1, 0, 0, 0, 0, 0, 0, -1 },
new int[] { -1, 0, 1, 1, 1, 1, 0, -1 }, new int[] { -1, 1, 1, 1, 1, 1, 1, -1 }, new int[] { -1, 0, 1, 1, 1, 1, 0, -1 },
new int[] { -1, 1, 1, 1, 1, 1, 1, -1 }, new int[] { -1, 1, 0, 0, 0, 0, 1, -1 },
new int[] { -2, -1, -1, -1, -1, -1, -1, -2 } });
positionScores.put(Type.PAWN,
new int[][] { new int[] { 0, 0, 0, 0, 0, 0, 0, 0 }, new int[] { 5, 5, 5, 5, 5, 5, 5, 5 }, new int[] { 1, 1, 2, 3, 3, 2, 1, 1 },
new int[] { 0, 0, 1, 3, 3, 1, 0, 0 }, new int[] { 0, 0, 0, 2, 2, 0, 0, 0 }, new int[] { 0, 0, -1, 0, 0, -1, 0, 0 },
new int[] { 0, 1, 1, -2, -2, 1, 1, 0 }, new int[] { 0, 0, 0, 0, 0, 0, 0, 0 } });
}
/** /**
* Initializes the board with the default chess starting position. * Initializes the board with the default chess starting position.
*/ */
@ -338,40 +304,6 @@ public class Board {
: getMoves(color).isEmpty() || log.getLast().halfmoveClock >= 50 ? GameState.STALEMATE : GameState.NORMAL; : getMoves(color).isEmpty() || log.getLast().halfmoveClock >= 50 ? GameState.STALEMATE : GameState.NORMAL;
} }
/**
* Evaluated the board.
*
* @param color The color to evaluate for
* @return An positive number representing how good the position is
*/
public int evaluate(Color color) {
int score = 0;
for (int i = 0; i < 8; i++)
for (int j = 0; j < 8; j++)
if (boardArr[i][j] != null && boardArr[i][j].getColor() == color) {
switch (boardArr[i][j].getType()) {
case QUEEN:
score += 90;
break;
case ROOK:
score += 50;
break;
case KNIGHT:
score += 30;
break;
case BISHOP:
score += 30;
break;
case PAWN:
score += 10;
break;
}
if (positionScores.containsKey(boardArr[i][j].getType()))
score += positionScores.get(boardArr[i][j].getType())[i][color == Color.WHITE ? j : 7 - j];
}
return score;
}
/** /**
* Initialized the board array with the default chess pieces and positions. * Initialized the board array with the default chess pieces and positions.
*/ */

View File

@ -1,11 +1,14 @@
package dev.kske.chess.game.ai; package dev.kske.chess.game.ai;
import java.util.HashMap;
import java.util.List; import java.util.List;
import java.util.Map;
import java.util.concurrent.Callable; import java.util.concurrent.Callable;
import dev.kske.chess.board.Board; import dev.kske.chess.board.Board;
import dev.kske.chess.board.Move; import dev.kske.chess.board.Move;
import dev.kske.chess.board.Piece.Color; import dev.kske.chess.board.Piece.Color;
import dev.kske.chess.board.Piece.Type;
/** /**
* Project: <strong>Chess</strong><br> * Project: <strong>Chess</strong><br>
@ -25,6 +28,40 @@ public class MoveProcessor implements Callable<ProcessingResult> {
private Move bestMove; private Move bestMove;
private static final Map<Type, int[][]> positionScores;
static {
positionScores = new HashMap<>();
positionScores.put(Type.KING,
new int[][] { new int[] { -3, -4, -4, -5, -5, -4, -4, -3 }, new int[] { -3, -4, -4, -5, -4, -4, -4, -3 },
new int[] { -3, -4, -4, -5, -4, -4, -4, -3 }, new int[] { -3, -4, -4, -5, -4, -4, -4, -3 },
new int[] { -2, -3, -3, -2, -2, -2, -2, -1 }, new int[] { -1, -2, -2, -2, -2, -2, -2, -1 },
new int[] { 2, 2, 0, 0, 0, 0, 2, 2 }, new int[] { 2, 3, 1, 0, 0, 1, 3, 2 } });
positionScores.put(Type.QUEEN,
new int[][] { new int[] { -2, -1, -1, -1, -1, -1, -1, -2 }, new int[] { -1, 0, 0, 0, 0, 0, 0, -1 },
new int[] { -1, 0, 1, 1, 1, 1, 0, -1 }, new int[] { -1, 0, 1, 1, 1, 1, 0, -1 }, new int[] { 0, 0, 1, 1, 1, 1, 0, -1 },
new int[] { -1, 1, 1, 1, 1, 1, 0, -1 }, new int[] { -1, 0, 1, 0, 0, 0, 0, -1 },
new int[] { -2, -1, -1, -1, -1, -1, -1, -2 } });
positionScores.put(Type.ROOK,
new int[][] { new int[] { 0, 0, 0, 0, 0, 0, 0, 0 }, new int[] { 1, 1, 1, 1, 1, 1, 1, 1 }, new int[] { -1, 0, 0, 0, 0, 0, 0, -1 },
new int[] { -1, 0, 0, 0, 0, 0, 0, -1 }, new int[] { -1, 0, 0, 0, 0, 0, 0, -1 }, new int[] { -1, 0, 0, 0, 0, 0, 0, -1 },
new int[] { -1, 0, 0, 0, 0, 0, 0, -1 }, new int[] { 0, 0, 0, 1, 1, 0, 0, 0 } });
positionScores.put(Type.KNIGHT,
new int[][] { new int[] { -5, -4, -3, -3, -3, -3, -4, -5 }, new int[] { -4, -2, 0, 0, 0, 0, -2, -4 },
new int[] { -3, 0, 1, 2, 2, 1, 0, -3 }, new int[] { -3, 1, 2, 2, 2, 2, 1, -3 }, new int[] { -3, 0, 2, 2, 2, 2, 0, -1 },
new int[] { -3, 1, 1, 2, 2, 1, 1, -3 }, new int[] { -4, -2, 0, 1, 1, 0, -2, -4 },
new int[] { -5, -4, -3, -3, -3, -3, -4, -5 } });
positionScores.put(Type.BISHOP,
new int[][] { new int[] { -2, -1, -1, -1, -1, -1, -1, 2 }, new int[] { -1, 0, 0, 0, 0, 0, 0, -1 },
new int[] { -1, 0, 1, 1, 1, 1, 0, -1 }, new int[] { -1, 1, 1, 1, 1, 1, 1, -1 }, new int[] { -1, 0, 1, 1, 1, 1, 0, -1 },
new int[] { -1, 1, 1, 1, 1, 1, 1, -1 }, new int[] { -1, 1, 0, 0, 0, 0, 1, -1 },
new int[] { -2, -1, -1, -1, -1, -1, -1, -2 } });
positionScores.put(Type.PAWN,
new int[][] { new int[] { 0, 0, 0, 0, 0, 0, 0, 0 }, new int[] { 5, 5, 5, 5, 5, 5, 5, 5 }, new int[] { 1, 1, 2, 3, 3, 2, 1, 1 },
new int[] { 0, 0, 1, 3, 3, 1, 0, 0 }, new int[] { 0, 0, 0, 2, 2, 0, 0, 0 }, new int[] { 0, 0, -1, 0, 0, -1, 0, 0 },
new int[] { 0, 1, 1, -2, -2, 1, 1, 0 }, new int[] { 0, 0, 0, 0, 0, 0, 0, 0 } });
}
public MoveProcessor(Board board, List<Move> rootMoves, Color color, int maxDepth, int alphaBetaThreshold) { public MoveProcessor(Board board, List<Move> rootMoves, Color color, int maxDepth, int alphaBetaThreshold) {
this.board = board; this.board = board;
this.rootMoves = rootMoves; this.rootMoves = rootMoves;
@ -43,8 +80,8 @@ public class MoveProcessor implements Callable<ProcessingResult> {
int bestValue = Integer.MIN_VALUE; int bestValue = Integer.MIN_VALUE;
for (Move move : moves) { for (Move move : moves) {
board.move(move); board.move(move);
int teamValue = board.evaluate(color); int teamValue = evaluate(board, color);
int enemyValue = board.evaluate(color.opposite()); int enemyValue = evaluate(board, color.opposite());
int valueChange = teamValue - enemyValue; int valueChange = teamValue - enemyValue;
if (depth < maxDepth && valueChange >= alphaBetaThreshold) if (depth < maxDepth && valueChange >= alphaBetaThreshold)
@ -59,4 +96,38 @@ public class MoveProcessor implements Callable<ProcessingResult> {
} }
return bestValue; return bestValue;
} }
/**
* Evaluated a board.
*
* @param color The color to evaluate for
* @return An positive number representing how good the position is
*/
private int evaluate(Board board, Color color) {
int score = 0;
for (int i = 0; i < 8; i++)
for (int j = 0; j < 8; j++)
if (board.getBoardArr()[i][j] != null && board.getBoardArr()[i][j].getColor() == color) {
switch (board.getBoardArr()[i][j].getType()) {
case QUEEN:
score += 90;
break;
case ROOK:
score += 50;
break;
case KNIGHT:
score += 30;
break;
case BISHOP:
score += 30;
break;
case PAWN:
score += 10;
break;
}
if (positionScores.containsKey(board.getBoardArr()[i][j].getType()))
score += positionScores.get(board.getBoardArr()[i][j].getType())[i][color == Color.WHITE ? j : 7 - j];
}
return score;
}
} }