/////////////
// FEN UTILS
- // Setup the initial random (assymetric) position
- static GenRandInitFen() {
+ // Setup the initial random (asymmetric) position
+ static GenRandInitFen(randomness) {
+ if (randomness == 0)
+ // Deterministic:
+ return "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w 0 1111 -";
+
let pieces = { w: new Array(8), b: new Array(8) };
- // Shuffle pieces on first and last rank
+ // Shuffle pieces on first (and last rank if randomness == 2)
for (let c of ["w", "b"]) {
+ if (c == 'b' && randomness == 1) {
+ pieces['b'] = pieces['w'];
+ break;
+ }
+
let positions = ArrayFun.range(8);
// Get random squares for bishops
//////////////////
// INITIALIZATION
- constructor(fen) {
- // In printDiagram() fen isn't supply because only getPpath() is used
- if (fen)
- this.re_init(fen);
- }
-
// Fen string fully describes the game state
- re_init(fen) {
+ constructor(fen) {
+ if (!fen)
+ // In printDiagram() fen isn't supply because only getPpath() is used
+ // TODO: find a better solution!
+ return;
const fenParsed = V.ParseFen(fen);
this.board = V.GetBoard(fenParsed.position);
this.turn = fenParsed.turn[0]; //[0] to work with MarseilleRules
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;
+ if (oneStep) continue outerLoop;
i += step[0];
j += step[1];
}
// (for engine and game end)
getAllValidMoves() {
const color = this.turn;
- const oppCol = V.GetOppCol(color);
let potentialMoves = [];
for (let i = 0; i < V.size.x; i++) {
for (let j = 0; j < V.size.y; j++) {
- // Next condition "!= oppCol" to work with checkered variant
- if (this.board[i][j] != V.EMPTY && this.getColor(i, j) != oppCol) {
+ if (this.getColor(i, j) == color) {
Array.prototype.push.apply(
potentialMoves,
this.getPotentialMovesFrom([i, j])
// Stop at the first move found
atLeastOneMove() {
const color = this.turn;
- const oppCol = V.GetOppCol(color);
for (let i = 0; i < V.size.x; i++) {
for (let j = 0; j < V.size.y; j++) {
- if (this.board[i][j] != V.EMPTY && this.getColor(i, j) != oppCol) {
+ if (this.getColor(i, j) == color) {
const moves = this.getPotentialMovesFrom([i, j]);
if (moves.length > 0) {
for (let k = 0; k < moves.length; k++) {
);
}
+ // Generic method for non-pawn pieces ("sliding or jumping"):
+ // is x,y attacked by a piece of color in array 'colors' ?
+ isAttackedBySlideNJump([x, y], colors, piece, steps, oneStep) {
+ for (let step of steps) {
+ let rx = x + step[0],
+ ry = y + step[1];
+ while (V.OnBoard(rx, ry) && this.board[rx][ry] == V.EMPTY && !oneStep) {
+ rx += step[0];
+ ry += step[1];
+ }
+ if (
+ V.OnBoard(rx, ry) &&
+ this.getPiece(rx, ry) === piece &&
+ colors.includes(this.getColor(rx, ry))
+ ) {
+ return true;
+ }
+ }
+ return false;
+ }
+
// Is square x,y attacked by 'colors' pawns ?
isAttackedByPawn([x, y], colors) {
for (let c of colors) {
- let pawnShift = c == "w" ? 1 : -1;
+ const pawnShift = c == "w" ? 1 : -1;
if (x + pawnShift >= 0 && x + pawnShift < V.size.x) {
for (let i of [-1, 1]) {
if (
);
}
- // Generic method for non-pawn pieces ("sliding or jumping"):
- // is x,y attacked by a piece of color in array 'colors' ?
- isAttackedBySlideNJump([x, y], colors, piece, steps, oneStep) {
- for (let step of steps) {
- let rx = x + step[0],
- ry = y + step[1];
- while (V.OnBoard(rx, ry) && this.board[rx][ry] == V.EMPTY && !oneStep) {
- rx += step[0];
- ry += step[1];
- }
- if (
- V.OnBoard(rx, ry) &&
- this.getPiece(rx, ry) === piece &&
- colors.includes(this.getColor(rx, ry))
- ) {
- return true;
- }
- }
- return false;
- }
-
// Is color under check after his move ?
underCheck(color) {
return this.isAttacked(this.kingPos[color], [V.GetOppCol(color)]);
return 3;
}
- // NOTE: works also for extinction chess because depth is 3...
getComputerMove() {
const maxeval = V.INFINITY;
const color = this.turn;
// Some variants may show a bigger moves list to the human (Switching),
// thus the argument "computer" below (which is generally ignored)
- let moves1 = this.getAllValidMoves("computer");
+ let moves1 = this.getAllValidMoves();
if (moves1.length == 0)
- //TODO: this situation should not happen
+ // TODO: this situation should not happen
return null;
- // Can I mate in 1 ? (for Magnetic & Extinction)
- for (let i of shuffle(ArrayFun.range(moves1.length))) {
- this.play(moves1[i]);
- let finish = Math.abs(this.evalPosition()) >= V.THRESHOLD_MATE;
- if (!finish) {
- const score = this.getCurrentScore();
- if (["1-0", "0-1"].includes(score)) finish = true;
- }
- this.undo(moves1[i]);
- if (finish) return moves1[i];
- }
-
// Rank moves using a min-max at depth 2
for (let i = 0; i < moves1.length; i++) {
// Initial self evaluation is very low: "I'm checkmated"
// Initial enemy evaluation is very low too, for him
eval2 = (color == "w" ? 1 : -1) * maxeval;
// Second half-move:
- let moves2 = this.getAllValidMoves("computer");
+ let moves2 = this.getAllValidMoves();
for (let j = 0; j < moves2.length; j++) {
this.play(moves2[j]);
const score2 = this.getCurrentScore();
moves1.sort((a, b) => {
return (color == "w" ? 1 : -1) * (b.eval - a.eval);
});
+// console.log(moves1.map(m => { return [this.getNotation(m), m.eval]; }));
let candidates = [0]; //indices of candidates moves
for (let j = 1; j < moves1.length && moves1[j].eval == moves1[0].eval; j++)
if (score != "*")
return score == "1/2" ? 0 : (score == "1-0" ? 1 : -1) * maxeval;
if (depth == 0) return this.evalPosition();
- const moves = this.getAllValidMoves("computer");
+ const moves = this.getAllValidMoves();
let v = color == "w" ? -maxeval : maxeval;
if (color == "w") {
for (let i = 0; i < moves.length; i++) {