getPotentialMovesFrom([x,y])
{
// Pre-check: is thing on this square immobilized?
- // In this case add potential suicide as a move "taking the immobilizer"
const piece = this.getPiece(x,y);
const color = this.getColor(x,y);
const oppCol = this.getOppCol(color);
const V = VariantRules;
const adjacentSteps = V.steps[V.ROOK].concat(V.steps[V.BISHOP]);
const [sizeX,sizeY] = V.size;
+ outerLoop:
for (let step of adjacentSteps)
{
const [i,j] = [x+step[0],y+step[1]];
&& this.getColor(i,j) == oppCol)
{
const oppPiece = this.getPiece(i,j);
- if (oppPiece == V.IMMOBILIZER
- || (oppPiece == V.BISHOP && piece == V.IMMOBILIZER))
+ if (oppPiece == V.BISHOP && piece == V.IMMOBILIZER)
+ return [];
+ if (oppPiece == V.IMMOBILIZER && ![V.BISHOP,V.IMMOBILIZER].includes(piece))
{
- return [ new Move({
- appear: [],
- vanish: [new PiPo({x:x,y:y,p:piece,c:color})],
- start: {x:x,y:y},
- end: {x:i,y:j}
- }) ];
+ // Moving is impossible only if this immobilizer is not neutralized
+ for (let step2 of adjacentSteps)
+ {
+ const [i2,j2] = [i+step2[0],j+step2[1]];
+ if (i2>=0 && i2<sizeX && j2>=0 && j2<sizeY
+ && this.board[i2][j2] != V.EMPTY && this.getColor(i2,j2) == color)
+ {
+ const friendlyPiece = this.getPiece(i2,j2);
+ if ([V.BISHOP,V.IMMOBILIZER].includes(friendlyPiece))
+ break outerLoop;
+ }
+ }
+ return []; //immobilizer isn't neutralized
}
}
}
return super.getPotentialQueenMoves(sq).concat(this.getKnightCaptures(sq));
}
- getPotentialBishopMoves(sq)
+ getPotentialBishopMoves([x,y])
{
- let moves = super.getPotentialQueenMoves(sq)
- .concat(this.getKnightCaptures(sq,"asChameleon"));
- // NOTE: no "addKingCaptures" because the king isn't captured
+ let moves = super.getPotentialQueenMoves([x,y])
+ .concat(this.getKnightCaptures([x,y],"asChameleon"));
this.addPawnCaptures(moves, "asChameleon");
this.addRookCaptures(moves, "asChameleon");
this.addQueenCaptures(moves, "asChameleon");
+ // Add king capture if it's within range
+ const oppKp = this.kingPos[this.getOppCol(this.turn)];
+ if (Math.abs(x-oppKp[0]) <= 1 && Math.abs(y-oppKp[1]) <= 1)
+ moves.push(this.getBasicMove([x,y],oppKp));
// Post-processing: merge similar moves, concatenating vanish arrays
let mergedMoves = {};
const [sizeX,sizeY] = VariantRules.size;
V.steps[V.ROOK].concat(V.steps[V.BISHOP]), "oneStep");
}
- // isAttacked() is OK because the immobilizer doesn't take
-
- isAttackedByPawn([x,y], colors)
+ atLeastOneMove()
{
- // Square (x,y) must be surrounded by two enemy pieces,
- // and one of them at least should be a pawn
- return false;
+ if (this.kingPos[this.turn][0] < 0)
+ return false;
+ return super.atLeastOneMove();
}
- isAttackedByRook(sq, colors)
+ underCheck(move)
{
- // Enemy king must be on same file and a rook on same row (or reverse)
- return false;
+ return false; //there is no check
}
- isAttackedByKnight(sq, colors)
+ getCheckSquares(move)
{
- // Square (x,y) must be on same line as a knight,
- // and there must be empty square(s) behind.
- return false;
- }
-
- isAttackedByBishop(sq, colors)
- {
- // switch on piece nature on square sq: a chameleon attack as this piece
- // ==> call the appropriate isAttackedBy... (exception of immobilizers)
- // Other exception: a chameleon cannot attack a chameleon (seemingly...)
- return false;
- }
-
- isAttackedByQueen(sq, colors)
- {
- // Square (x,y) must be adjacent to a queen, and the queen must have
- // some free space in the opposite direction from (x,y)
- return false;
+ const c = this.getOppCol(this.turn); //opponent
+ const saveKingPos = this.kingPos[c]; //king might be taken
+ this.play(move);
+ // The only way to be "under check" is to have lost the king (thus game over)
+ let res = this.kingPos[c][0] < 0
+ ? [ JSON.parse(JSON.stringify(saveKingPos)) ]
+ : [ ];
+ this.undo(move);
+ return res;
}
updateVariables(move)
{
- // Just update king position
+ // Just update king(s) position(s)
const piece = this.getPiece(move.start.x,move.start.y);
const c = this.getColor(move.start.x,move.start.y);
if (piece == VariantRules.KING && move.appear.length > 0)
this.kingPos[c][0] = move.appear[0].x;
this.kingPos[c][1] = move.appear[0].y;
}
+ // Does this move takes opponent's king?
+ const oppCol = this.getOppCol(c);
+ for (let i=1; i<move.vanish.length; i++)
+ {
+ if (move.vanish[i].p == VariantRules.KING)
+ {
+ this.kingPos[oppCol] = [-1,-1];
+ break;
+ }
+ }
+ }
+
+ unupdateVariables(move)
+ {
+ super.unupdateVariables(move);
+ const c = this.getColor(move.start.x,move.start.y);
+ const oppCol = this.getOppCol(c);
+ if (this.kingPos[oppCol][0] < 0)
+ {
+ // Last move took opponent's king
+ for (let i=1; i<move.vanish.length; i++)
+ {
+ const psq = move.vanish[i];
+ if (psq.p == 'k')
+ {
+ this.kingPos[oppCol] = [psq.x, psq.y];
+ break;
+ }
+ }
+ }
}
checkGameEnd()
{
- // No valid move: game is lost (stalemate is a win)
+ // Stalemate, or our king disappeared
return this.turn == "w" ? "0-1" : "1-0";
}
static get SEARCH_DEPTH() { return 2; } //TODO?
+ static get THRESHOLD_MATE() {
+ return 500; //checkmates evals may be slightly below 1000
+ }
+
static GenRandInitFen()
{
let pieces = { "w": new Array(8), "b": new Array(8) };
{
return "0000"; //TODO: or "-" ?
}
-
- getNotation(move)
- {
- if (move.appear.length == 0)
- {
- const startSquare =
- String.fromCharCode(97 + move.start.y) + (VariantRules.size[0]-move.start.x);
- return "^" + startSquare; //suicide
- }
- return super.getNotation(move);
- }
}
projects / vchess.git / blobdiff