const oppCol = V.GetOppCol(this.turn);
moves.forEach(m => {
this.play(m);
+ let allAttacks = [];
- // 1) What is attacked?
- let attacked = {};
- for (let i=0; i<V.size.x; i++) {
- for (let j=0; j<V.size.y; j++) {
- if (this.getColor(i,j) == oppCol && this.isAttacked([i,j], color))
- attacked[i+"_"+j] = [i,j];
+ // While something has been captured:
+ // remove it, and keep looking for captures
+ outerLoop: while (true) {
+
+ // 1) What is attacked?
+ let attacked = {};
+ for (let i=0; i<V.size.x; i++) {
+ for (let j=0; j<V.size.y; j++) {
+ if (this.getColor(i,j) == oppCol && this.isAttacked([i,j], color))
+ attacked[i+"_"+j] = [i,j];
+ }
}
- }
+ if (Object.keys(attacked).length == 0) break outerLoop;
- // 2) Among attacked pieces, which cannot escape capture?
- // Avoid "oppMoves = this.getAllValidMoves();" => infinite recursion
- outerLoop: for (let i=0; i<V.size.x; i++) {
- for (let j=0; j<V.size.y; j++) {
- if (this.getColor(i,j) == oppCol) {
- let oppMoves = [];
- switch (this.getPiece(i, j)) {
- case V.PAWN:
- oppMoves = this.getPotentialPawnMoves([i, j]);
- break;
- case V.ROOK:
- oppMoves = this.getPotentialRookMoves([i, j]);
- break;
- case V.KNIGHT:
- oppMoves = this.getPotentialKnightMoves([i, j]);
- break;
- case V.BISHOP:
- oppMoves = this.getPotentialBishopMoves([i, j]);
- break;
- case V.QUEEN:
- oppMoves = this.getPotentialQueenMoves([i, j]);
- break;
- case V.KING:
- // Do not allow castling to escape from check
- oppMoves = super.getSlideNJumpMoves(
- [x, y],
- V.steps[V.ROOK].concat(V.steps[V.BISHOP]),
- "oneStep"
- );
- break;
- }
- for (let om of oppMoves) {
- V.PlayOnBoard(this.board, om);
- Object.values(attacked).forEach(sq => {
- const origSq = [sq[0], sq[1]];
- if (om.start.x == sq[0] && om.start.y == sq[1])
- // Piece moved:
- sq = [om.appear[0].x, om.appear[0].y];
- if (!this.isAttacked(sq, color))
- delete attacked[origSq[0]+"_"+origSq[1]];
- });
- V.UndoOnBoard(this.board, om);
- if (Object.keys(attacked).length == 0)
- // No need to explore more moves
- break outerLoop;
+ // 2) Among attacked pieces, which cannot escape capture?
+ // Avoid "oppMoves = this.getAllValidMoves();" => infinite recursion
+ for (let i=0; i<V.size.x; i++) {
+ for (let j=0; j<V.size.y; j++) {
+ if (this.getColor(i,j) == oppCol) {
+ let oppMoves = [];
+ switch (this.getPiece(i, j)) {
+ case V.PAWN:
+ oppMoves = this.getPotentialPawnMoves([i, j]);
+ break;
+ case V.ROOK:
+ oppMoves = this.getPotentialRookMoves([i, j]);
+ break;
+ case V.KNIGHT:
+ oppMoves = this.getPotentialKnightMoves([i, j]);
+ break;
+ case V.BISHOP:
+ oppMoves = this.getPotentialBishopMoves([i, j]);
+ break;
+ case V.QUEEN:
+ oppMoves = this.getPotentialQueenMoves([i, j]);
+ break;
+ case V.KING:
+ // Do not allow castling to escape from check
+ oppMoves = super.getSlideNJumpMoves(
+ [i, j],
+ V.steps[V.ROOK].concat(V.steps[V.BISHOP]),
+ "oneStep"
+ );
+ break;
+ }
+ for (let om of oppMoves) {
+ V.PlayOnBoard(this.board, om);
+ Object.values(attacked).forEach(sq => {
+ const origSq = [sq[0], sq[1]];
+ if (om.start.x == sq[0] && om.start.y == sq[1])
+ // Piece moved:
+ sq = [om.appear[0].x, om.appear[0].y];
+ if (!this.isAttacked(sq, color))
+ delete attacked[origSq[0]+"_"+origSq[1]];
+ });
+ V.UndoOnBoard(this.board, om);
+ if (Object.keys(attacked).length == 0)
+ // No need to explore more moves
+ break outerLoop;
+ }
}
}
}
+
+ // 3) Add mate-captures and remove pieces from board:
+ Object.keys(attacked).forEach(k => {
+ allAttacks.push({
+ sq: attacked[k],
+ p: this.getPiece(attacked[k][0], attacked[k][1])
+ });
+ this.board[attacked[k][0]][attacked[k][1]] = V.EMPTY;
+ });
}
- // 3) Add mate-captures:
- Object.values(attacked).forEach(sq => {
- m.vanish.push(new PiPo({
- x: sq[0],
- y: sq[1],
- c: oppCol,
- p: this.getPiece(sq[0], sq[1])
- }));
+ // Put removed pieces back on board:
+ allAttacks.forEach(v => {
+ this.board[v.sq[0]][v.sq[1]] = oppCol + v.p;
});
-
this.undo(m);
+ allAttacks.forEach(v => {
+ m.vanish.push(
+ new PiPo({
+ x: v.sq[0],
+ y: v.sq[1],
+ c: oppCol,
+ p: v.p
+ })
+ );
+ });
});
return moves;
projects / vchess.git / commitdiff
