return false;
}
- // "pa": piece (as a square) doing this push/pull action
- getActionMoves([sx, sy], [ex, ey], pa) {
- const color = this.getColor(sx, sy);
- const lastRank = (color == 'w' ? 0 : 7);
- const piece = this.getPiece(sx, sy);
+ // Step is right, just add (push/pull) moves in this direction
+ // Direction is assumed normalized.
+ getMovesInDirection([x, y], [dx, dy], nbSteps) {
+ nbSteps = nbSteps || 8; //max 8 steps anyway
+ let [i, j] = [x + dx, y + dy];
let moves = [];
- if (ex == lastRank && piece == V.PAWN) {
- // Promotion by push or pull
- V.PawnSpecs.promotions.forEach(p => {
- let move = super.getBasicMove([sx, sy], [ex, ey], { c: color, p: p });
- moves.push(move);
- });
- } else moves.push(super.getBasicMove([sx, sy], [ex, ey]));
+ const color = this.getColor(x, y);
+ const piece = this.getPiece(x, y);
+ const lastRank = (color == 'w' ? 0 : 7);
+ while (V.OnBoard(i, j) && this.board[i][j] == V.EMPTY) {
+ if (i == lastRank && piece == V.PAWN) {
+ // Promotion by push or pull
+ V.PawnSpecs.promotions.forEach(p => {
+ let move = super.getBasicMove([x, y], [i, j], { c: color, p: p });
+ moves.push(move);
+ });
+ }
+ else moves.push(super.getBasicMove([x, y], [i, j]));
+ }
+ if (!V.OnBoard(i, j) && piece != V.KING) {
+ // Add special "exit" move, by "taking king"
+ moves.push(
+ new Move({
+ start: { x: x, y: y },
+ end: JSON.parse(JSON.stringify(this.kingPos[color])),
+ appear: [],
+ vanish: [{ x: x, y: y, c: color, p: piece }]
+ })
+ );
+ }
return moves;
}
- // Actions on piece on square "sq", by color "color"
- // NOTE: to push a piece out of the board, make it slide until our piece
- // (doing the action, moving or not)
- getPactions(sq, color) {
- const [x, y] = sq;
- let moves = [];
- let squares = {};
- const oppCol = V.GetOppCol(color);
- // Look in all directions for a "color" piece
- for (let step of V.steps[V.KNIGHT]) {
- const xx = x + step[0],
- yy = y + step[1];
- if (
- V.OnBoard(xx, yy) &&
- this.getPiece(xx, yy) == V.KNIGHT &&
- this.getColor(xx, yy) == color
- ) {
- const px = x - step[0],
- py = y - step[1];
- if (V.OnBoard(px, py)) {
- if (this.board[px][py] == V.EMPTY) {
- const hash = "s" + px + py;
- if (!squares[hash]) {
- squares[hash] = true;
- Array.prototype.push.apply(
- moves,
- this.getActionMoves([x, y], [px, py], [xx, yy])
- );
- }
- else { //add piece doing action
- }
- }
- } else {
- const hash = "s" + xx + yy;
- if (!squares[hash]) {
- squares[hash] = true;
- moves.push(
- new Move({
- start: { x: x, y: y },
- end: { x: xx, y: yy },
- appear: [],
- vanish: [
- new PiPo({
- x: x,
- y: y,
- p: this.getPiece(x, y),
- c: oppCol
- })
- ]
- })
- );
- }
- }
+ // Normalize direction to know the step
+ getNormalizedDirection([dx, dy]) {
+ const absDir = [Math.abs(dx), Math.abs(dy)];
+ let divisor = 0;
+ if (absDir[0] != 0 && absDir[1] != 0 && absDir[0] != absDir[1])
+ // Knight
+ divisor = Math.min(absDir[0], absDir[1]);
+ else
+ // Standard slider (or maybe a pawn or king: same)
+ divisor = Math.max(absDir[0], absDir[1]);
+ return [dx / divisor, dy / divisor];
+ }
+
+ // There is something on x2,y2, maybe our color, pushed/pulled
+ static IsAprioriValidMove([x1, y1], [x2, y2]) {
+ const color1 = this.getColor(x1, y1);
+ const color2 = this.getColor(x2, y2);
+ const pawnShift = (color1 == 'w' ? -1 : 1);
+ const pawnStartRank = (color1 == 'w' ? 6 : 1);
+ const deltaX = Math.abs(x1 - x2);
+ const deltaY = Math.abs(y1 - y2);
+ switch (this.getPiece(x1, y1)) {
+ case V.PAWN:
+ return (
+ (
+ color1 == color2 &&
+ y1 == y2 &&
+ (
+ x1 + pawnShift == x2 ||
+ x1 == pawnStartRank && x1 + 2 * pawnShift == x2
+ )
+ )
+ ||
+ (
+ color1 != color2 &&
+ deltaY == 1 &&
+ x1 + pawnShift == x2
+ )
+ );
+ case V.ROOK:
+ return (x1 == x2 || y1 == y2);
+ case V.KNIGHT: {
+ return (deltaX + deltaY == 3 && (deltaX == 1 || deltaY == 1));
}
+ case V.BISHOP:
+ return (deltaX == deltaY);
+ case V.QUEEN:
+ return (
+ (deltaX == 0 || deltaY == 0 || deltaX == deltaY)
+ );
+ case V.KING:
+ return (deltaX <= 1 && deltaY <= 1);
}
- for (let step in V.steps[V.ROOK]) {
- // (+ if color is ours, pawn pushes) king, rook and queen
- // --> pawns special case can push from a little distance if on 2nd rank (or 1st rank)
- }
- for (let step in V.steps[V.BISHOP]) {
- // King, bishop, queen, and possibly pawns attacks (if color is enemy)
- }
- return moves;
+ return false;
}
// NOTE: for pushes, play the pushed piece first.
// for pulls: play the piece doing the action first
- // If castle, then no options available next (just re-click)
+ // NOTE: to push a piece out of the board, make it slide until its king
getPotentialMovesFrom([x, y]) {
const color = this.turn;
if (this.subTurn == 1) {
- // Free to play any move or action:
- return (
- super.getPotentialMovesFrom([x, y])
- .concat(this.getPactions([x, y], color))
- );
+ // Free to play any move:
+ const moves = super.getPotentialMovesFrom([x, y])
+ // Structure to avoid adding moves twice (can be action & move)
+ let hashMoves = {};
+ moves.forEach(m => { hashMoves[getMoveHash(m)] = true; });
+ const getMoveHash = (m) => {
+ return V.CoordsToSquare(m.start) + V.CoordsToSquare(m.end);
+ };
+ const addMoves = (dir, nbSteps) => {
+ const newMoves =
+ this.getMovesInDirection([x, y], [-dir[0], -dir[1]], nbSteps)
+ .filter(m => !movesHash[getMoveHash(m)]);
+ newMoves.forEach(m => { hashMoves[getMoveHash(m)] = true; });
+ Array.prototype.push.apply(moves, newMoves);
+ };
+ const pawnShift = (color == 'w' ? -1 : 1);
+ const pawnStartRank = (color == 'w' ? 6 : 1);
+ // [x, y] is pushed by 'color'
+ for (let step of V.steps[V.KNIGHT]) {
+ const [i, j] = [x + step[0], y + step[1]];
+ if (V.OnBoard(i, j) && this.board[i][j] != V.EMPTY) {
+ // Only can move away from a knight (can pull but must move first)
+ Array.prototype.push.apply(
+ moves,
+ this.getMovesInDirection([x, y], [-step[0], -step[1]], 1)
+ .filter(m => !movesHash[getMoveHash(m)])
+ );
+ }
+ }
+ for (let step in V.steps[V.ROOK].concat(V.steps[V.BISHOP])) {
+ let [i, j] = [x + step[0], y + step[1]];
+ while (V.OnBoard(i, j) && this.board[i][j] == V.EMPTY) {
+ i += step[0];
+ j += step[1];
+ }
+ if (
+ V.OnBoard(i, j) &&
+ this.board[i][j] != V.EMPTY &&
+ this.getColor(i, j) == color
+ ) {
+ const deltaX = Math.abs(i - x);
+ const deltaY = Math.abs(j - y);
+ // Can a priori go both ways, except with pawns
+ switch (this.getPiece(i, j)) {
+ case V.PAWN:
+ if (deltaX <= 2 && deltaY <= 1) {
+ const pColor = this.getColor(x, y);
+ if (pColor == color && deltaY == 0) {
+ // Pushed forward
+ const maxSteps = (i == pawnStartRank && deltaX == 1 ? 2 : 1);
+ addMoves(step, maxSteps);
+ }
+ else if (pColor != color && deltaY == 1 && deltaX == 1)
+ // Pushed diagonally
+ addMoves(step, 1);
+ }
+ break;
+ case V.ROOK:
+ if (deltaX == 0 || deltaY == 0) addMoves(step);
+ break;
+ case V.KNIGHT:
+ if (deltaX + deltaY == 3 && (deltaX == 1 || deltaY == 1))
+ addMoves(step, 1);
+ break;
+ case V.BISHOP:
+ if (deltaX == deltaY) addMoves(step);
+ break;
+ case V.QUEEN:
+ if (deltaX == 0 || deltaY == 0 || deltaX == deltaY)
+ addMoves(step);
+ break;
+ case V.KING:
+ if (deltaX <= 1 && deltaY <= 1) addMoves(step, 1);
+ break;
+ }
+ }
+ }
+ return moves;
}
// If subTurn == 2 then we should have a first move,
- // which restrict what we can play now.
- // Case 1: an opponent's piece moved: we can only move the piece which
- // did the action, in the moving direction.
- // Case 2: one of our pieces moved: either by action or by itself.
- // Just check if it could be a normal move. If yes, allow both.
+ // which restrict what we can play now: only in the first move direction
+ // NOTE: no need for knight or pawn checks, because the move will be
+ // naturally limited in those cases.
const L = this.firstMove.length;
const fm = this.firstMove[L-1];
- if (fm.vanish[0].c != color) {
- // Case 1: TODO
+ if (fm.appear.length == 2 && fm.vanish.length == 2)
+ // Castle: no real move playable then.
+ return [];
+ if (fm.appear.length == 0) {
+ // Piece at subTurn 1 just exited the board.
+ // Can I be a piece which caused the exit?
+ this.undo(fm);
+ const moveOk = V.IsAprioriValidMove([x, y], [fm.start.x, fm.start.y]);
+ this.play(fm);
+ if (moveOk) {
+ // Seems so:
+ const dir = this.getNormalizedDirection(
+ [fm.start.x - x, fm.start.y - y]);
+ return this.getMovesInDirection([x, y], dir);
+ }
}
else {
- // Case 2: TODO
- // Use fm.start.x, fm.start.y, fm.end.x, fm.end.y, fm.vanish[0].c
- // Search for the piece doing the action "pa": the action type
- // is deduced from pa relative positon then.
+ const dirM = this.getNormalizedDirection(
+ [fm.end.x - fm.start.x, fm.end.y - fm.start.y]);
+ const dir = this.getNormalizedDirection(
+ [fm.start.x - x, fm.start.y - y]);
+ // Normalized directions should match:
+ if (dir[0] == dirM[0] && dir[1] == dirM[1])
+ return this.getMovesInDirection([x, y], dir);
}
+ return [];
}
// Does m2 un-do m1 ? (to disallow undoing actions)
}
doClick(square) {
- // If subTurn == 2 && square is the final square of last move,
- // then return an empty move
- const L = this.firstMove.length;
+ // If subTurn == 2 && square is empty && !underCheck,
+ // then return an empty move, allowing to "pass" subTurn2
if (
this.subTurn == 2 &&
- square.x == this.firstMove[L-1].end.x &&
- square.y == this.firstMove[L-1].end.y
+ this.board[square.x][square.y] == V.EMPTY &&
+ !this.underCheck(this.turn)
) {
return {
appear: [],
projects / vchess.git / commitdiff
