--- /dev/null
+import { ChessRules, PiPo, Move } from "@/base_rules";
+import { ArrayFun } from "@/utils/array";
+import { shuffle } from "@/utils/alea";
+
+export class RococoRules extends ChessRules {
+ static get HasFlags() {
+ return false;
+ }
+
+ static get HasEnpassant() {
+ return false;
+ }
+
+ static get PIECES() {
+ return ChessRules.PIECES.concat([V.IMMOBILIZER]);
+ }
+
+ getPpath(b) {
+ if (b[1] == "m")
+ //'m' for Immobilizer (I is too similar to 1)
+ return "Rococo/" + b;
+ return b; //usual piece
+ }
+
+ getPPpath(m) {
+ // The only "choice" case is between a swap and a mutual destruction:
+ // show empty square in case of mutual destruction.
+ if (m.appear.length == 0) return "Rococo/empty";
+ return m.appear[0].c + m.appear[0].p;
+ }
+
+ setOtherVariables(fen) {
+ // No castling, but checks, so keep track of kings
+ this.kingPos = { w: [-1, -1], b: [-1, -1] };
+ const fenParts = fen.split(" ");
+ const position = fenParts[0].split("/");
+ for (let i = 0; i < position.length; i++) {
+ let k = 0;
+ for (let j = 0; j < position[i].length; j++) {
+ switch (position[i].charAt(j)) {
+ case "k":
+ this.kingPos["b"] = [i, k];
+ break;
+ case "K":
+ this.kingPos["w"] = [i, k];
+ break;
+ default: {
+ const num = parseInt(position[i].charAt(j));
+ if (!isNaN(num)) k += num - 1;
+ }
+ }
+ k++;
+ }
+ }
+ // Local stack of swaps:
+ this.smoves = [];
+ const smove = V.ParseFen(fen).smove;
+ if (smove == "-") this.smoves.push(null);
+ else {
+ this.smoves.push({
+ start: ChessRules.SquareToCoords(smove.substr(0, 2)),
+ end: ChessRules.SquareToCoords(smove.substr(2))
+ });
+ }
+ }
+
+ static ParseFen(fen) {
+ return Object.assign(
+ ChessRules.ParseFen(fen),
+ { smove: fen.split(" ")[3] }
+ );
+ }
+
+ static IsGoodFen(fen) {
+ if (!ChessRules.IsGoodFen(fen)) return false;
+ const fenParts = fen.split(" ");
+ if (fenParts.length != 4) return false;
+ if (fenParts[3] != "-" && !fenParts[3].match(/^([a-h][1-8]){2}$/))
+ return false;
+ return true;
+ }
+
+ getSmove(move) {
+ if (move.appear.length == 2)
+ return { start: move.start, end: move.end };
+ return null;
+ }
+
+ static get size() {
+ // Add the "capturing edge"
+ return { x: 10, y: 10 };
+ }
+
+ static get IMMOBILIZER() {
+ return "m";
+ }
+ // Although other pieces keep their names here for coding simplicity,
+ // keep in mind that:
+ // - a "rook" is a swapper, exchanging positions and "capturing" by
+ // mutual destruction only.
+ // - a "knight" is a long-leaper, capturing as in draughts
+ // - a "bishop" is a chameleon, capturing as its prey
+ // - a "queen" is a withdrawer+advancer, capturing by moving away from
+ // pieces or advancing in front of them.
+
+ // Is piece on square (x,y) immobilized?
+ isImmobilized([x, y]) {
+ const piece = this.getPiece(x, y);
+ const oppCol = V.GetOppCol(this.getColor(x, y));
+ const adjacentSteps = V.steps[V.ROOK].concat(V.steps[V.BISHOP]);
+ for (let step of adjacentSteps) {
+ const [i, j] = [x + step[0], y + step[1]];
+ if (
+ V.OnBoard(i, j) &&
+ this.board[i][j] != V.EMPTY &&
+ this.getColor(i, j) == oppCol
+ ) {
+ const oppPiece = this.getPiece(i, j);
+ if (oppPiece == V.IMMOBILIZER) return [i, j];
+ // Only immobilizers are immobilized by chameleons:
+ if (oppPiece == V.BISHOP && piece == V.IMMOBILIZER) return [i, j];
+ }
+ }
+ return null;
+ }
+
+ static OnEdge(x, y) {
+ return x == 0 || y == 0 || x == V.size.x - 1 || y == V.size.y - 1;
+ }
+
+ getPotentialMovesFrom([x, y]) {
+ // Pre-check: is thing on this square immobilized?
+ const imSq = this.isImmobilized([x, y]);
+ if (!!imSq) {
+ // Only option is suicide:
+ return [
+ new Move({
+ start: { x: x, y: y },
+ end: { x: imSq[0], y: imSq[1] },
+ appear: [],
+ vanish: [
+ new PiPo({
+ x: x,
+ y: y,
+ c: this.getColor(x, y),
+ p: this.getPiece(x, y)
+ })
+ ]
+ })
+ ];
+ }
+ let moves = [];
+ switch (this.getPiece(x, y)) {
+ case V.IMMOBILIZER:
+ moves = this.getPotentialImmobilizerMoves([x, y]);
+ break;
+ default:
+ moves = super.getPotentialMovesFrom([x, y]);
+ }
+ // Post-processing: prune redundant non-minimal capturing moves,
+ // and non-capturing moves ending on the edge:
+ moves.forEach(m => {
+ // Useful precomputation
+ m.dist = Math.abs(m.end.x - m.start.x) + Math.abs(m.end.y - m.start.y);
+ });
+ return moves.filter(m => {
+ if (!V.OnEdge(m.end.x, m.end.y)) return true;
+ // End on the edge:
+ if (m.vanish.length == 1) return false;
+ // Capture or swap: only captures get filtered
+ if (m.appear.length == 2) return true;
+ // Can we find other moves with a shorter path to achieve the same
+ // capture? Apply to queens and knights.
+ if (
+ moves.some(mv => {
+ return (
+ mv.dist < m.dist &&
+ mv.vanish.length == m.vanish.length &&
+ mv.vanish.every(v => {
+ return m.vanish.some(vv => {
+ return (
+ vv.x == v.x && vv.y == v.y && vv.c == v.c && vv.p == v.p
+ );
+ });
+ })
+ );
+ })
+ ) {
+ return false;
+ }
+ return true;
+ });
+ // NOTE: not removing "dist" field; shouldn't matter much...
+ }
+
+ getSlideNJumpMoves([x, y], steps, oneStep) {
+ const piece = this.getPiece(x, y);
+ let moves = [];
+ outerLoop: for (let step of steps) {
+ let i = x + step[0];
+ let j = y + step[1];
+ while (V.OnBoard(i, j) && this.board[i][j] == V.EMPTY) {
+ moves.push(this.getBasicMove([x, y], [i, j]));
+ if (oneStep !== undefined) continue outerLoop;
+ i += step[0];
+ j += step[1];
+ }
+ // Only king can take on occupied square:
+ if (piece == V.KING && V.OnBoard(i, j) && this.canTake([x, y], [i, j]))
+ moves.push(this.getBasicMove([x, y], [i, j]));
+ }
+ return moves;
+ }
+
+ // "Cannon/grasshopper pawn"
+ getPotentialPawnMoves([x, y]) {
+ const oppCol = V.GetOppCol(this.turn);
+ let moves = [];
+ const adjacentSteps = V.steps[V.ROOK].concat(V.steps[V.BISHOP]);
+ adjacentSteps.forEach(step => {
+ const [i, j] = [x + step[0], y + step[1]];
+ if (V.OnBoard(i, j)) {
+ if (this.board[i][j] == V.EMPTY)
+ moves.push(this.getBasicMove([x, y], [i, j]));
+ else {
+ // Try to leap over:
+ const [ii, jj] = [i + step[0], j + step[1]];
+ if (V.OnBoard(ii, jj) && this.getColor(ii, jj) == oppCol)
+ moves.push(this.getBasicMove([x, y], [ii, jj]));
+ }
+ }
+ });
+ return moves;
+ }
+
+ // NOTE: not really captures, but let's keep the name
+ getRookCaptures([x, y], byChameleon) {
+ let moves = [];
+ const oppCol = V.GetOppCol(this.turn);
+ // Simple: if something is visible, we can swap
+ V.steps[V.ROOK].concat(V.steps[V.BISHOP]).forEach(step => {
+ 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.getColor(i, j) == oppCol) {
+ const oppPiece = this.getPiece(i, j);
+ if (!byChameleon || oppPiece == V.ROOK) {
+ let m = this.getBasicMove([x, y], [i, j]);
+ m.appear.push(
+ new PiPo({
+ x: x,
+ y: y,
+ c: oppCol,
+ p: this.getPiece(i, j)
+ })
+ );
+ moves.push(m);
+ if (i == x + step[0] && j == y + step[1]) {
+ // Add mutual destruction option:
+ m = new Move({
+ start: { x: x, y: y},
+ end: { x: i, y: j },
+ appear: [],
+ // TODO: is copying necessary here?
+ vanish: JSON.parse(JSON.stringify(m.vanish))
+ });
+ moves.push(m);
+ }
+ }
+ }
+ });
+ return moves;
+ }
+
+ // Swapper
+ getPotentialRookMoves(sq) {
+ return super.getPotentialQueenMoves(sq).concat(this.getRookCaptures(sq));
+ }
+
+ getKnightCaptures(startSquare, byChameleon) {
+ // Look in every direction for captures
+ const steps = V.steps[V.ROOK].concat(V.steps[V.BISHOP]);
+ const color = this.turn;
+ const oppCol = V.GetOppCol(color);
+ let moves = [];
+ const [x, y] = [startSquare[0], startSquare[1]];
+ const piece = this.getPiece(x, y); //might be a chameleon!
+ outerLoop: for (let step of steps) {
+ 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.getColor(i, j) == color ||
+ (!!byChameleon && this.getPiece(i, j) != V.KNIGHT)
+ ) {
+ continue;
+ }
+ // last(thing), cur(thing) : stop if "cur" is our color,
+ // or beyond board limits, or if "last" isn't empty and cur neither.
+ // Otherwise, if cur is empty then add move until cur square;
+ // if cur is occupied then stop if !!byChameleon and the square not
+ // occupied by a leaper.
+ let last = [i, j];
+ let cur = [i + step[0], j + step[1]];
+ let vanished = [new PiPo({ x: x, y: y, c: color, p: piece })];
+ while (V.OnBoard(cur[0], cur[1])) {
+ if (this.board[last[0]][last[1]] != V.EMPTY) {
+ const oppPiece = this.getPiece(last[0], last[1]);
+ if (!!byChameleon && oppPiece != V.KNIGHT) continue outerLoop;
+ // Something to eat:
+ vanished.push(
+ new PiPo({ x: last[0], y: last[1], c: oppCol, p: oppPiece })
+ );
+ }
+ if (this.board[cur[0]][cur[1]] != V.EMPTY) {
+ if (
+ this.getColor(cur[0], cur[1]) == color ||
+ this.board[last[0]][last[1]] != V.EMPTY
+ ) {
+ //TODO: redundant test
+ continue outerLoop;
+ }
+ } else {
+ moves.push(
+ new Move({
+ appear: [new PiPo({ x: cur[0], y: cur[1], c: color, p: piece })],
+ vanish: JSON.parse(JSON.stringify(vanished)), //TODO: required?
+ start: { x: x, y: y },
+ end: { x: cur[0], y: cur[1] }
+ })
+ );
+ }
+ last = [last[0] + step[0], last[1] + step[1]];
+ cur = [cur[0] + step[0], cur[1] + step[1]];
+ }
+ }
+ return moves;
+ }
+
+ // Long-leaper
+ getPotentialKnightMoves(sq) {
+ return super.getPotentialQueenMoves(sq).concat(this.getKnightCaptures(sq));
+ }
+
+ // Chameleon
+ getPotentialBishopMoves([x, y]) {
+ const oppCol = V.GetOppCol(this.turn);
+ let moves = super
+ .getPotentialQueenMoves([x, y])
+ .concat(this.getKnightCaptures([x, y], "asChameleon"))
+ .concat(this.getRookCaptures([x, y], "asChameleon"));
+ // No "king capture" because king cannot remain under check
+ this.addQueenCaptures(moves, "asChameleon");
+ // Also add pawn captures (as a pawn):
+ const adjacentSteps = V.steps[V.ROOK].concat(V.steps[V.BISHOP]);
+ adjacentSteps.forEach(step => {
+ const [i, j] = [x + step[0], y + step[1]];
+ const [ii, jj] = [i + step[0], j + step[1]];
+ // Try to leap over (i,j):
+ if (
+ V.OnBoard(ii, jj) &&
+ this.board[i][j] != V.EMPTY &&
+ this.board[ii][jj] != V.EMPTY &&
+ this.getColor(ii, jj) == oppCol &&
+ this.getPiece(ii, jj) == V.PAWN
+ ) {
+ moves.push(this.getBasicMove([x, y], [ii, jj]));
+ }
+ });
+ // Post-processing: merge similar moves, concatenating vanish arrays
+ let mergedMoves = {};
+ moves.forEach(m => {
+ const key = m.end.x + V.size.x * m.end.y;
+ if (!mergedMoves[key]) mergedMoves[key] = m;
+ else {
+ for (let i = 1; i < m.vanish.length; i++)
+ mergedMoves[key].vanish.push(m.vanish[i]);
+ }
+ });
+ return Object.values(mergedMoves);
+ }
+
+ addQueenCaptures(moves, byChameleon) {
+ if (moves.length == 0) return;
+ const [x, y] = [moves[0].start.x, moves[0].start.y];
+ const adjacentSteps = V.steps[V.ROOK].concat(V.steps[V.BISHOP]);
+ let capturingDirStart = {};
+ const oppCol = V.GetOppCol(this.turn);
+ // Useful precomputation:
+ adjacentSteps.forEach(step => {
+ const [i, j] = [x + step[0], y + step[1]];
+ if (
+ V.OnBoard(i, j) &&
+ this.board[i][j] != V.EMPTY &&
+ this.getColor(i, j) == oppCol &&
+ (!byChameleon || this.getPiece(i, j) == V.QUEEN)
+ ) {
+ capturingDirStart[step[0] + "_" + step[1]] = this.getPiece(i, j);
+ }
+ });
+ moves.forEach(m => {
+ const step = [
+ m.end.x != x ? (m.end.x - x) / Math.abs(m.end.x - x) : 0,
+ m.end.y != y ? (m.end.y - y) / Math.abs(m.end.y - y) : 0
+ ];
+ // TODO: this test should be done only once per direction
+ const capture = capturingDirStart[(-step[0]) + "_" + (-step[1])];
+ if (!!capture) {
+ const [i, j] = [x - step[0], y - step[1]];
+ m.vanish.push(
+ new PiPo({
+ x: i,
+ y: j,
+ p: capture,
+ c: oppCol
+ })
+ );
+ }
+ // Also test the end (advancer effect)
+ const [i, j] = [m.end.x + step[0], m.end.y + step[1]];
+ if (
+ V.OnBoard(i, j) &&
+ this.board[i][j] != V.EMPTY &&
+ this.getColor(i, j) == oppCol &&
+ (!byChameleon || this.getPiece(i, j) == V.QUEEN)
+ ) {
+ m.vanish.push(
+ new PiPo({
+ x: i,
+ y: j,
+ p: this.getPiece(i, j),
+ c: oppCol
+ })
+ );
+ }
+ });
+ }
+
+ // Withdrawer + advancer: "pushme-pullyu"
+ getPotentialQueenMoves(sq) {
+ let moves = super.getPotentialQueenMoves(sq);
+ this.addQueenCaptures(moves);
+ return moves;
+ }
+
+ getPotentialImmobilizerMoves(sq) {
+ // Immobilizer doesn't capture
+ return super.getPotentialQueenMoves(sq);
+ }
+
+ // Does m2 un-do m1 ? (to disallow undoing swaps)
+ oppositeMoves(m1, m2) {
+ return (
+ !!m1 &&
+ m2.appear.length == 2 &&
+ m1.start.x == m2.start.x &&
+ m1.end.x == m2.end.x &&
+ m1.start.y == m2.start.y &&
+ m1.end.y == m2.end.y
+ );
+ }
+
+ filterValid(moves) {
+ if (moves.length == 0) return [];
+ const color = this.turn;
+ return (
+ super.filterValid(
+ moves.filter(m => {
+ const L = this.smoves.length; //at least 1: init from FEN
+ return !this.oppositeMoves(this.smoves[L - 1], m);
+ })
+ )
+ );
+ }
+
+ // isAttacked() is OK because the immobilizer doesn't take
+
+ isAttackedByPawn([x, y], color) {
+ // Attacked if an enemy pawn stands just behind an immediate obstacle:
+ const adjacentSteps = V.steps[V.ROOK].concat(V.steps[V.BISHOP]);
+ for (let step of adjacentSteps) {
+ const [i, j] = [x + step[0], y + step[1]];
+ const [ii, jj] = [i + step[0], j + step[1]];
+ if (
+ V.OnBoard(ii, jj) &&
+ this.board[i][j] != V.EMPTY &&
+ this.board[ii][jj] != V.EMPTY &&
+ this.getColor(ii, jj) == color &&
+ this.getPiece(ii, jj) == V.PAWN &&
+ !this.isImmobilized([ii, jj])
+ ) {
+ return true;
+ }
+ }
+ return false;
+ }
+
+ isAttackedByRook([x, y], color) {
+ // The only way a swapper can take is by mutual destruction when the
+ // enemy piece stands just next:
+ const adjacentSteps = V.steps[V.ROOK].concat(V.steps[V.BISHOP]);
+ for (let step of adjacentSteps) {
+ const [i, j] = [x + step[0], y + step[1]];
+ if (
+ V.OnBoard(i, j) &&
+ this.board[i][j] != V.EMPTY &&
+ this.getColor(i, j) == color &&
+ this.getPiece(i, j) == V.ROOK &&
+ !this.isImmobilized([i, j])
+ ) {
+ return true;
+ }
+ }
+ return false;
+ }
+
+ isAttackedByKnight([x, y], color) {
+ // Square (x,y) must be on same line as a knight,
+ // and there must be empty square(s) behind.
+ const steps = V.steps[V.ROOK].concat(V.steps[V.BISHOP]);
+ outerLoop: for (let step of steps) {
+ const [i0, j0] = [x + step[0], y + step[1]];
+ if (V.OnBoard(i0, j0) && this.board[i0][j0] == V.EMPTY) {
+ // Try in opposite direction:
+ let [i, j] = [x - step[0], y - step[1]];
+ while (V.OnBoard(i, j)) {
+ while (V.OnBoard(i, j) && this.board[i][j] == V.EMPTY) {
+ i -= step[0];
+ j -= step[1];
+ }
+ if (V.OnBoard(i, j)) {
+ if (this.getColor(i, j) == color) {
+ if (
+ this.getPiece(i, j) == V.KNIGHT &&
+ !this.isImmobilized([i, j])
+ )
+ return true;
+ continue outerLoop;
+ }
+ // [else] Our color,
+ // could be captured *if there was an empty space*
+ if (this.board[i + step[0]][j + step[1]] != V.EMPTY)
+ continue outerLoop;
+ i -= step[0];
+ j -= step[1];
+ }
+ }
+ }
+ }
+ return false;
+ }
+
+ isAttackedByBishop([x, y], color) {
+ // We cheat a little here: since this function is used exclusively for
+ // the king, it's enough to check the immediate surrounding of the square.
+ const adjacentSteps = V.steps[V.ROOK].concat(V.steps[V.BISHOP]);
+ for (let step of adjacentSteps) {
+ const [i, j] = [x + step[0], y + step[1]];
+ if (
+ V.OnBoard(i, j) &&
+ this.board[i][j] != V.EMPTY &&
+ this.getColor(i, j) == color &&
+ this.getPiece(i, j) == V.BISHOP &&
+ !this.isImmobilized([i, j])
+ ) {
+ return true;
+ }
+ }
+ return false;
+ }
+
+ isAttackedByQueen([x, y], color) {
+ // Is there a queen in view?
+ const adjacentSteps = V.steps[V.ROOK].concat(V.steps[V.BISHOP]);
+ for (let step of adjacentSteps) {
+ 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.getColor(i, j) == color &&
+ this.getPiece(i, j) == V.QUEEN
+ ) {
+ // Two cases: the queen is at 2 steps at least, or just close
+ // but maybe with enough space behind to withdraw.
+ let attacked = false;
+ if (i == x + step[0] && j == y + step[1]) {
+ const [ii, jj] = [i + step[0], j + step[1]];
+ if (V.OnBoard(ii, jj) && this.board[ii][jj] == V.EMPTY)
+ attacked = true;
+ }
+ else attacked = true;
+ if (attacked && !this.isImmobilized([i, j])) return true;
+ }
+ }
+ return false;
+ }
+
+ isAttackedByKing([x, y], color) {
+ const steps = V.steps[V.ROOK].concat(V.steps[V.BISHOP]);
+ for (let step of steps) {
+ let rx = x + step[0],
+ ry = y + step[1];
+ if (
+ V.OnBoard(rx, ry) &&
+ this.getPiece(rx, ry) === V.KING &&
+ this.getColor(rx, ry) == color &&
+ !this.isImmobilized([rx, ry])
+ ) {
+ return true;
+ }
+ }
+ return false;
+ }
+
+ static GenRandInitFen(randomness) {
+ if (randomness == 0) {
+ return (
+ "91/1rnbkqbnm1/1pppppppp1/91/91/91/91/1PPPPPPPP1/1MNBQKBNR1/91 w 0 -"
+ );
+ }
+
+ let pieces = { w: new Array(8), b: new Array(8) };
+ // Shuffle pieces on first and last rank
+ for (let c of ["w", "b"]) {
+ if (c == 'b' && randomness == 1) {
+ pieces['b'] = pieces['w'];
+ break;
+ }
+
+ // Get random squares for every piece, totally freely
+ let positions = shuffle(ArrayFun.range(8));
+ const composition = ['r', 'm', 'n', 'n', 'q', 'q', 'b', 'k'];
+ for (let i = 0; i < 8; i++) pieces[c][positions[i]] = composition[i];
+ }
+ return (
+ "91/1" + pieces["b"].join("") +
+ "1/1pppppppp1/91/91/91/91/1PPPPPPPP1/1" +
+ pieces["w"].join("").toUpperCase() + "1/91 w 0 -"
+ );
+ }
+
+ getSmoveFen() {
+ const L = this.smoves.length;
+ return (
+ !this.smoves[L - 1]
+ ? "-"
+ : ChessRules.CoordsToSquare(this.smoves[L - 1].start) +
+ ChessRules.CoordsToSquare(this.smoves[L - 1].end)
+ );
+ }
+
+ getFen() {
+ return super.getFen() + " " + this.getSmoveFen();
+ }
+
+ getFenForRepeat() {
+ return super.getFenForRepeat() + "_" + this.getSmoveFen();
+ }
+
+ postPlay(move) {
+ super.postPlay(move);
+ this.smoves.push(this.getSmove(move));
+ }
+
+ postUndo(move) {
+ super.postUndo(move);
+ this.smoves.pop();
+ }
+
+ static get VALUES() {
+ return {
+ p: 1,
+ r: 2,
+ n: 5,
+ b: 3,
+ q: 5,
+ m: 5,
+ k: 1000
+ };
+ }
+
+ static get SEARCH_DEPTH() {
+ return 2;
+ }
+
+ getNotation(move) {
+ const initialSquare = V.CoordsToSquare(move.start);
+ const finalSquare = V.CoordsToSquare(move.end);
+ if (move.appear.length == 0) {
+ // Suicide 'S' or mutual destruction 'D':
+ return (
+ initialSquare + (move.vanish.length == 1 ? "S" : "D" + finalSquare)
+ );
+ }
+ let notation = undefined;
+ if (move.appear[0].p == V.PAWN) {
+ // Pawn: generally ambiguous short notation, so we use full description
+ notation = "P" + initialSquare + finalSquare;
+ } else if (move.appear[0].p == V.KING)
+ notation = "K" + (move.vanish.length > 1 ? "x" : "") + finalSquare;
+ else notation = move.appear[0].p.toUpperCase() + finalSquare;
+ // Add a capture mark (not describing what is captured...):
+ if (move.vanish.length > 1 && move.appear[0].p != V.KING) notation += "X";
+ return notation;
+ }
+};
projects / vchess.git / blobdiff