From: Benjamin Auder Date: Wed, 10 Apr 2019 14:42:39 +0000 (+0200) Subject: Fixing computer play X-Git-Url: https://git.auder.net/variants/Baroque/complete_rules.html?a=commitdiff_plain;h=1c9f093dad69e4c7b6d2b42cb5e0bd3bc7224ec9;p=vchess.git Fixing computer play --- diff --git a/client/src/base_rules.js b/client/src/base_rules.js index bb2edc43..087b4f5b 100644 --- a/client/src/base_rules.js +++ b/client/src/base_rules.js @@ -6,1317 +6,1318 @@ import { random, sample, shuffle } from "@/utils/alea"; export const PiPo = class PiPo //Piece+Position { - // o: {piece[p], color[c], posX[x], posY[y]} - constructor(o) - { - this.p = o.p; - this.c = o.c; - this.x = o.x; - this.y = o.y; - } + // o: {piece[p], color[c], posX[x], posY[y]} + constructor(o) + { + this.p = o.p; + this.c = o.c; + this.x = o.x; + this.y = o.y; + } } // TODO: for animation, moves should contains "moving" and "fading" maybe... export const Move = class Move { - // o: {appear, vanish, [start,] [end,]} - // appear,vanish = arrays of PiPo - // start,end = coordinates to apply to trigger move visually (think castle) - constructor(o) - { - this.appear = o.appear; - this.vanish = o.vanish; - this.start = !!o.start ? o.start : {x:o.vanish[0].x, y:o.vanish[0].y}; - this.end = !!o.end ? o.end : {x:o.appear[0].x, y:o.appear[0].y}; - } + // o: {appear, vanish, [start,] [end,]} + // appear,vanish = arrays of PiPo + // start,end = coordinates to apply to trigger move visually (think castle) + constructor(o) + { + this.appear = o.appear; + this.vanish = o.vanish; + this.start = !!o.start ? o.start : {x:o.vanish[0].x, y:o.vanish[0].y}; + this.end = !!o.end ? o.end : {x:o.appear[0].x, y:o.appear[0].y}; + } } // NOTE: x coords = top to bottom; y = left to right (from white player perspective) export const ChessRules = class ChessRules { - ////////////// - // MISC UTILS - - static get HasFlags() { return true; } //some variants don't have flags - - static get HasEnpassant() { return true; } //some variants don't have ep. - - // Path to pieces - static getPpath(b) - { - return b; //usual pieces in pieces/ folder - } - - // Turn "wb" into "B" (for FEN) - static board2fen(b) - { - return b[0]=='w' ? b[1].toUpperCase() : b[1]; - } - - // Turn "p" into "bp" (for board) - static fen2board(f) - { - return f.charCodeAt()<=90 ? "w"+f.toLowerCase() : "b"+f; - } - - // Check if FEN describe a position - static IsGoodFen(fen) - { - const fenParsed = V.ParseFen(fen); - // 1) Check position - if (!V.IsGoodPosition(fenParsed.position)) - return false; - // 2) Check turn - if (!fenParsed.turn || !V.IsGoodTurn(fenParsed.turn)) - return false; - // 3) Check moves count - if (!fenParsed.movesCount || !(parseInt(fenParsed.movesCount) >= 0)) - return false; - // 4) Check flags - if (V.HasFlags && (!fenParsed.flags || !V.IsGoodFlags(fenParsed.flags))) - return false; - // 5) Check enpassant - if (V.HasEnpassant && - (!fenParsed.enpassant || !V.IsGoodEnpassant(fenParsed.enpassant))) - { - return false; - } - return true; - } - - // Is position part of the FEN a priori correct? - static IsGoodPosition(position) - { - if (position.length == 0) - return false; - const rows = position.split("/"); - if (rows.length != V.size.x) - return false; - for (let row of rows) - { - let sumElts = 0; - for (let i=0; i d (column number to letter) - static CoordToColumn(colnum) - { - return String.fromCharCode(97 + colnum); - } - - // d --> 3 (column letter to number) - static ColumnToCoord(column) - { - return column.charCodeAt(0) - 97; - } - - // a4 --> {x:3,y:0} - static SquareToCoords(sq) - { - return { - // NOTE: column is always one char => max 26 columns - // row is counted from black side => subtraction - x: V.size.x - parseInt(sq.substr(1)), - y: sq[0].charCodeAt() - 97 - }; - } - - // {x:0,y:4} --> e8 - static CoordsToSquare(coords) - { - return V.CoordToColumn(coords.y) + (V.size.x - coords.x); - } - - // Aggregates flags into one object - aggregateFlags() - { - return this.castleFlags; - } - - // Reverse operation - disaggregateFlags(flags) - { - this.castleFlags = flags; - } - - // En-passant square, if any - getEpSquare(moveOrSquare) - { - if (!moveOrSquare) - return undefined; - if (typeof moveOrSquare === "string") - { - const square = moveOrSquare; - if (square == "-") - return undefined; - return V.SquareToCoords(square); - } - // Argument is a move: - const move = moveOrSquare; - const [sx,sy,ex] = [move.start.x,move.start.y,move.end.x]; - // TODO: next conditions are first for Atomic, and third for Checkered - if (move.appear.length > 0 && move.appear[0].p == V.PAWN && ["w","b"].includes(move.appear[0].c) && Math.abs(sx - ex) == 2) - { - return { - x: (sx + ex)/2, - y: sy - }; - } - return undefined; //default - } - - // Can thing on square1 take thing on square2 - canTake([x1,y1], [x2,y2]) - { - return this.getColor(x1,y1) !== this.getColor(x2,y2); - } - - // Is (x,y) on the chessboard? - static OnBoard(x,y) - { - return (x>=0 && x=0 && y 0) - { - // Add empty squares in-between - position += emptyCount; - emptyCount = 0; - } - position += V.board2fen(this.board[i][j]); - } - } - if (emptyCount > 0) - { - // "Flush remainder" - position += emptyCount; - } - if (i < V.size.x - 1) - position += "/"; //separate rows - } - return position; - } - - getTurnFen() - { - return this.turn; - } - - // Flags part of the FEN string - getFlagsFen() - { - let flags = ""; - // Add castling flags - for (let i of ['w','b']) - { - for (let j=0; j<2; j++) - flags += (this.castleFlags[i][j] ? '1' : '0'); - } - return flags; - } - - // Enpassant part of the FEN string - getEnpassantFen() - { - const L = this.epSquares.length; - if (!this.epSquares[L-1]) - return "-"; //no en-passant - return V.CoordsToSquare(this.epSquares[L-1]); - } - - // Turn position fen into double array ["wb","wp","bk",...] - static GetBoard(position) - { - const rows = position.split("/"); - let board = ArrayFun.init(V.size.x, V.size.y, ""); - for (let i=0; i= 0 && x+shiftX < sizeX) - { - const finalPieces = x + shiftX == lastRank - ? [V.ROOK,V.KNIGHT,V.BISHOP,V.QUEEN] - : [V.PAWN] - // One square forward - if (this.board[x+shiftX][y] == V.EMPTY) - { - for (let piece of finalPieces) - { - moves.push(this.getBasicMove([x,y], [x+shiftX,y], - {c:pawnColor,p:piece})); - } - // Next condition because pawns on 1st rank can generally jump - if ([startRank,firstRank].includes(x) - && this.board[x+2*shiftX][y] == V.EMPTY) - { - // Two squares jump - moves.push(this.getBasicMove([x,y], [x+2*shiftX,y])); - } - } - // Captures - for (let shiftY of [-1,1]) - { - if (y + shiftY >= 0 && y + shiftY < sizeY - && this.board[x+shiftX][y+shiftY] != V.EMPTY - && this.canTake([x,y], [x+shiftX,y+shiftY])) - { - for (let piece of finalPieces) - { - moves.push(this.getBasicMove([x,y], [x+shiftX,y+shiftY], - {c:pawnColor,p:piece})); - } - } - } - } - - if (V.HasEnpassant) - { - // En passant - const Lep = this.epSquares.length; - const epSquare = this.epSquares[Lep-1]; //always at least one element - if (!!epSquare && epSquare.x == x+shiftX && Math.abs(epSquare.y - y) == 1) - { - let enpassantMove = this.getBasicMove([x,y], [epSquare.x,epSquare.y]); - enpassantMove.vanish.push({ - x: x, - y: epSquare.y, - p: 'p', - c: this.getColor(x,epSquare.y) - }); - moves.push(enpassantMove); - } - } - - return moves; - } - - // What are the rook moves from square x,y ? - getPotentialRookMoves(sq) - { - return this.getSlideNJumpMoves(sq, V.steps[V.ROOK]); - } - - // What are the knight moves from square x,y ? - getPotentialKnightMoves(sq) - { - return this.getSlideNJumpMoves(sq, V.steps[V.KNIGHT], "oneStep"); - } - - // What are the bishop moves from square x,y ? - getPotentialBishopMoves(sq) - { - return this.getSlideNJumpMoves(sq, V.steps[V.BISHOP]); - } - - // What are the queen moves from square x,y ? - getPotentialQueenMoves(sq) - { - return this.getSlideNJumpMoves(sq, - V.steps[V.ROOK].concat(V.steps[V.BISHOP])); - } - - // What are the king moves from square x,y ? - getPotentialKingMoves(sq) - { - // Initialize with normal moves - let moves = this.getSlideNJumpMoves(sq, - V.steps[V.ROOK].concat(V.steps[V.BISHOP]), "oneStep"); - return moves.concat(this.getCastleMoves(sq)); - } - - getCastleMoves([x,y]) - { - const c = this.getColor(x,y); - if (x != (c=="w" ? V.size.x-1 : 0) || y != this.INIT_COL_KING[c]) - return []; //x isn't first rank, or king has moved (shortcut) - - // Castling ? - const oppCol = V.GetOppCol(c); - let moves = []; - let i = 0; - const finalSquares = [ [2,3], [V.size.y-2,V.size.y-3] ]; //king, then rook - castlingCheck: - for (let castleSide=0; castleSide < 2; castleSide++) //large, then small - { - if (!this.castleFlags[c][castleSide]) - continue; - // If this code is reached, rooks and king are on initial position - - // Nothing on the path of the king ? - // (And no checks; OK also if y==finalSquare) - let step = finalSquares[castleSide][0] < y ? -1 : 1; - for (i=y; i!=finalSquares[castleSide][0]; i+=step) - { - if (this.isAttacked([x,i], [oppCol]) || (this.board[x][i] != V.EMPTY && - // NOTE: next check is enough, because of chessboard constraints - (this.getColor(x,i) != c - || ![V.KING,V.ROOK].includes(this.getPiece(x,i))))) - { - continue castlingCheck; - } - } - - // Nothing on the path to the rook? - step = castleSide == 0 ? -1 : 1; - for (i = y + step; i != this.INIT_COL_ROOK[c][castleSide]; i += step) - { - if (this.board[x][i] != V.EMPTY) - continue castlingCheck; - } - const rookPos = this.INIT_COL_ROOK[c][castleSide]; - - // Nothing on final squares, except maybe king and castling rook? - for (i=0; i<2; i++) - { - if (this.board[x][finalSquares[castleSide][i]] != V.EMPTY && - this.getPiece(x,finalSquares[castleSide][i]) != V.KING && - finalSquares[castleSide][i] != rookPos) - { - continue castlingCheck; - } - } - - // If this code is reached, castle is valid - moves.push( new Move({ - appear: [ - new PiPo({x:x,y:finalSquares[castleSide][0],p:V.KING,c:c}), - new PiPo({x:x,y:finalSquares[castleSide][1],p:V.ROOK,c:c})], - vanish: [ - new PiPo({x:x,y:y,p:V.KING,c:c}), - new PiPo({x:x,y:rookPos,p:V.ROOK,c:c})], - end: Math.abs(y - rookPos) <= 2 - ? {x:x, y:rookPos} - : {x:x, y:y + 2 * (castleSide==0 ? -1 : 1)} - }) ); - } - - return moves; - } - - //////////////////// - // MOVES VALIDATION - - // For the interface: possible moves for the current turn from square sq - getPossibleMovesFrom(sq) - { - return this.filterValid( this.getPotentialMovesFrom(sq) ); - } - - // TODO: promotions (into R,B,N,Q) should be filtered only once - filterValid(moves) - { - if (moves.length == 0) - return []; - const color = this.turn; - return moves.filter(m => { - this.play(m); - const res = !this.underCheck(color); - this.undo(m); - return res; - }); - } - - // Search for all valid moves considering current turn - // (for engine and game end) - getAllValidMoves() - { - const color = this.turn; - const oppCol = V.GetOppCol(color); - let potentialMoves = []; - for (let i=0; i 0) - { - for (let k=0; k 0) - return true; - } - } - } - } - } - return false; - } - - // Check if pieces of color in 'colors' are attacking (king) on square x,y - isAttacked(sq, colors) - { - return (this.isAttackedByPawn(sq, colors) - || this.isAttackedByRook(sq, colors) - || this.isAttackedByKnight(sq, colors) - || this.isAttackedByBishop(sq, colors) - || this.isAttackedByQueen(sq, colors) - || this.isAttackedByKing(sq, colors)); - } - - // Is square x,y attacked by 'colors' pawns ? - isAttackedByPawn([x,y], colors) - { - for (let c of colors) - { - let pawnShift = (c=="w" ? 1 : -1); - if (x+pawnShift>=0 && x+pawnShift=0 && y+i= 1) - { - // Usual case, something is moved - piece = move.vanish[0].p; - c = move.vanish[0].c; - } - else - { - // Crazyhouse-like variants - piece = move.appear[0].p; - c = move.appear[0].c; - } - if (c == "c") //if (!["w","b"].includes(c)) - { - // 'c = move.vanish[0].c' doesn't work for Checkered - c = V.GetOppCol(this.turn); - } - const firstRank = (c == "w" ? V.size.x-1 : 0); - - // Update king position + flags - if (piece == V.KING && move.appear.length > 0) - { - this.kingPos[c][0] = move.appear[0].x; - this.kingPos[c][1] = move.appear[0].y; - if (V.HasFlags) - this.castleFlags[c] = [false,false]; - return; - } - if (V.HasFlags) - { - // Update castling flags if rooks are moved - const oppCol = V.GetOppCol(c); - const oppFirstRank = (V.size.x-1) - firstRank; - if (move.start.x == firstRank //our rook moves? - && this.INIT_COL_ROOK[c].includes(move.start.y)) - { - const flagIdx = (move.start.y == this.INIT_COL_ROOK[c][0] ? 0 : 1); - this.castleFlags[c][flagIdx] = false; - } - else if (move.end.x == oppFirstRank //we took opponent rook? - && this.INIT_COL_ROOK[oppCol].includes(move.end.y)) - { - const flagIdx = (move.end.y == this.INIT_COL_ROOK[oppCol][0] ? 0 : 1); - this.castleFlags[oppCol][flagIdx] = false; - } - } - } - - // After move is undo-ed *and flags resetted*, un-update other variables - // TODO: more symmetry, by storing flags increment in move (?!) - unupdateVariables(move) - { - // (Potentially) Reset king position - const c = this.getColor(move.start.x,move.start.y); - if (this.getPiece(move.start.x,move.start.y) == V.KING) - this.kingPos[c] = [move.start.x, move.start.y]; - } - - play(move) - { - // DEBUG: -// if (!this.states) this.states = []; -// const stateFen = this.getBaseFen() + this.getTurnFen() + this.getFlagsFen(); -// this.states.push(stateFen); - - if (V.HasFlags) - move.flags = JSON.stringify(this.aggregateFlags()); //save flags (for undo) - if (V.HasEnpassant) - this.epSquares.push( this.getEpSquare(move) ); - if (!move.color) - move.color = this.turn; //for interface - V.PlayOnBoard(this.board, move); - this.turn = V.GetOppCol(this.turn); - this.movesCount++; - this.updateVariables(move); - } - - undo(move) - { - if (V.HasEnpassant) - this.epSquares.pop(); - if (V.HasFlags) - this.disaggregateFlags(JSON.parse(move.flags)); - V.UndoOnBoard(this.board, move); - this.turn = V.GetOppCol(this.turn); - this.movesCount--; - this.unupdateVariables(move); - - // DEBUG: -// const stateFen = this.getBaseFen() + this.getTurnFen() + this.getFlagsFen(); -// if (stateFen != this.states[this.states.length-1]) debugger; -// this.states.pop(); - } - - /////////////// - // END OF GAME - - // What is the score ? (Interesting if game is over) - getCurrentScore() - { - if (this.atLeastOneMove()) // game not over - return "*"; - - // Game over - const color = this.turn; - // No valid move: stalemate or checkmate? - if (!this.isAttacked(this.kingPos[color], [V.GetOppCol(color)])) - return "1/2"; - // OK, checkmate - return (color == "w" ? "0-1" : "1-0"); - } - - /////////////// - // ENGINE PLAY - - // Pieces values - static get VALUES() - { - return { - 'p': 1, - 'r': 5, - 'n': 3, - 'b': 3, - 'q': 9, - 'k': 1000 - }; - } - - // "Checkmate" (unreachable eval) - static get INFINITY() { return 9999; } - - // At this value or above, the game is over - static get THRESHOLD_MATE() { return V.INFINITY; } - - // Search depth: 2 for high branching factor, 4 for small (Loser chess, eg.) - static get SEARCH_DEPTH() { return 3; } - - // Assumption: at least one legal move - // 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"); - - // 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 eval2)) - { - eval2 = evalPos; - } - this.undo(moves2[j]); - } - } - else - eval2 = (score1=="1/2" ? 0 : (score1=="1-0" ? 1 : -1) * maxeval); - if ((color=="w" && eval2 > moves1[i].eval) - || (color=="b" && eval2 < moves1[i].eval)) - { - moves1[i].eval = eval2; - } - this.undo(moves1[i]); - } - moves1.sort( (a,b) => { return (color=="w" ? 1 : -1) * (b.eval - a.eval); }); - - let candidates = [0]; //indices of candidates moves - for (let j=1; j= 3: may take a while, so we control time - const timeStart = Date.now(); - - // Skip depth 3+ if we found a checkmate (or if we are checkmated in 1...) - if (V.SEARCH_DEPTH >= 3 && Math.abs(moves1[0].eval) < V.THRESHOLD_MATE) - { - for (let i=0; i= 5000) //more than 5 seconds - return currentBest; //depth 2 at least - this.play(moves1[i]); - // 0.1 * oldEval : heuristic to avoid some bad moves (not all...) - moves1[i].eval = 0.1*moves1[i].eval + - this.alphabeta(V.SEARCH_DEPTH-1, -maxeval, maxeval); - this.undo(moves1[i]); - } - moves1.sort( (a,b) => { - return (color=="w" ? 1 : -1) * (b.eval - a.eval); }); - } - else - return currentBest; -// console.log(moves1.map(m => { return [this.getNotation(m), m.eval]; })); - - candidates = [0]; - for (let j=1; j= 0)) + return false; + // 4) Check flags + if (V.HasFlags && (!fenParsed.flags || !V.IsGoodFlags(fenParsed.flags))) + return false; + // 5) Check enpassant + if (V.HasEnpassant && + (!fenParsed.enpassant || !V.IsGoodEnpassant(fenParsed.enpassant))) + { + return false; + } + return true; + } + + // Is position part of the FEN a priori correct? + static IsGoodPosition(position) + { + if (position.length == 0) + return false; + const rows = position.split("/"); + if (rows.length != V.size.x) + return false; + for (let row of rows) + { + let sumElts = 0; + for (let i=0; i d (column number to letter) + static CoordToColumn(colnum) + { + return String.fromCharCode(97 + colnum); + } + + // d --> 3 (column letter to number) + static ColumnToCoord(column) + { + return column.charCodeAt(0) - 97; + } + + // a4 --> {x:3,y:0} + static SquareToCoords(sq) + { + return { + // NOTE: column is always one char => max 26 columns + // row is counted from black side => subtraction + x: V.size.x - parseInt(sq.substr(1)), + y: sq[0].charCodeAt() - 97 + }; + } + + // {x:0,y:4} --> e8 + static CoordsToSquare(coords) + { + return V.CoordToColumn(coords.y) + (V.size.x - coords.x); + } + + // Aggregates flags into one object + aggregateFlags() + { + return this.castleFlags; + } + + // Reverse operation + disaggregateFlags(flags) + { + this.castleFlags = flags; + } + + // En-passant square, if any + getEpSquare(moveOrSquare) + { + if (!moveOrSquare) + return undefined; + if (typeof moveOrSquare === "string") + { + const square = moveOrSquare; + if (square == "-") + return undefined; + return V.SquareToCoords(square); + } + // Argument is a move: + const move = moveOrSquare; + const [sx,sy,ex] = [move.start.x,move.start.y,move.end.x]; + // TODO: next conditions are first for Atomic, and last for Checkered + if (move.appear.length > 0 && Math.abs(sx - ex) == 2 + && move.appear[0].p == V.PAWN && ["w","b"].includes(move.appear[0].c)) + { + return { + x: (sx + ex)/2, + y: sy + }; + } + return undefined; //default + } + + // Can thing on square1 take thing on square2 + canTake([x1,y1], [x2,y2]) + { + return this.getColor(x1,y1) !== this.getColor(x2,y2); + } + + // Is (x,y) on the chessboard? + static OnBoard(x,y) + { + return (x>=0 && x=0 && y 0) + { + // Add empty squares in-between + position += emptyCount; + emptyCount = 0; + } + position += V.board2fen(this.board[i][j]); + } + } + if (emptyCount > 0) + { + // "Flush remainder" + position += emptyCount; + } + if (i < V.size.x - 1) + position += "/"; //separate rows + } + return position; + } + + getTurnFen() + { + return this.turn; + } + + // Flags part of the FEN string + getFlagsFen() + { + let flags = ""; + // Add castling flags + for (let i of ['w','b']) + { + for (let j=0; j<2; j++) + flags += (this.castleFlags[i][j] ? '1' : '0'); + } + return flags; + } + + // Enpassant part of the FEN string + getEnpassantFen() + { + const L = this.epSquares.length; + if (!this.epSquares[L-1]) + return "-"; //no en-passant + return V.CoordsToSquare(this.epSquares[L-1]); + } + + // Turn position fen into double array ["wb","wp","bk",...] + static GetBoard(position) + { + const rows = position.split("/"); + let board = ArrayFun.init(V.size.x, V.size.y, ""); + for (let i=0; i= 0 && x+shiftX < sizeX) + { + const finalPieces = x + shiftX == lastRank + ? [V.ROOK,V.KNIGHT,V.BISHOP,V.QUEEN] + : [V.PAWN] + // One square forward + if (this.board[x+shiftX][y] == V.EMPTY) + { + for (let piece of finalPieces) + { + moves.push(this.getBasicMove([x,y], [x+shiftX,y], + {c:pawnColor,p:piece})); + } + // Next condition because pawns on 1st rank can generally jump + if ([startRank,firstRank].includes(x) + && this.board[x+2*shiftX][y] == V.EMPTY) + { + // Two squares jump + moves.push(this.getBasicMove([x,y], [x+2*shiftX,y])); + } + } + // Captures + for (let shiftY of [-1,1]) + { + if (y + shiftY >= 0 && y + shiftY < sizeY + && this.board[x+shiftX][y+shiftY] != V.EMPTY + && this.canTake([x,y], [x+shiftX,y+shiftY])) + { + for (let piece of finalPieces) + { + moves.push(this.getBasicMove([x,y], [x+shiftX,y+shiftY], + {c:pawnColor,p:piece})); + } + } + } + } + + if (V.HasEnpassant) + { + // En passant + const Lep = this.epSquares.length; + const epSquare = this.epSquares[Lep-1]; //always at least one element + if (!!epSquare && epSquare.x == x+shiftX && Math.abs(epSquare.y - y) == 1) + { + let enpassantMove = this.getBasicMove([x,y], [epSquare.x,epSquare.y]); + enpassantMove.vanish.push({ + x: x, + y: epSquare.y, + p: 'p', + c: this.getColor(x,epSquare.y) + }); + moves.push(enpassantMove); + } + } + + return moves; + } + + // What are the rook moves from square x,y ? + getPotentialRookMoves(sq) + { + return this.getSlideNJumpMoves(sq, V.steps[V.ROOK]); + } + + // What are the knight moves from square x,y ? + getPotentialKnightMoves(sq) + { + return this.getSlideNJumpMoves(sq, V.steps[V.KNIGHT], "oneStep"); + } + + // What are the bishop moves from square x,y ? + getPotentialBishopMoves(sq) + { + return this.getSlideNJumpMoves(sq, V.steps[V.BISHOP]); + } + + // What are the queen moves from square x,y ? + getPotentialQueenMoves(sq) + { + return this.getSlideNJumpMoves(sq, + V.steps[V.ROOK].concat(V.steps[V.BISHOP])); + } + + // What are the king moves from square x,y ? + getPotentialKingMoves(sq) + { + // Initialize with normal moves + let moves = this.getSlideNJumpMoves(sq, + V.steps[V.ROOK].concat(V.steps[V.BISHOP]), "oneStep"); + return moves.concat(this.getCastleMoves(sq)); + } + + getCastleMoves([x,y]) + { + const c = this.getColor(x,y); + if (x != (c=="w" ? V.size.x-1 : 0) || y != this.INIT_COL_KING[c]) + return []; //x isn't first rank, or king has moved (shortcut) + + // Castling ? + const oppCol = V.GetOppCol(c); + let moves = []; + let i = 0; + const finalSquares = [ [2,3], [V.size.y-2,V.size.y-3] ]; //king, then rook + castlingCheck: + for (let castleSide=0; castleSide < 2; castleSide++) //large, then small + { + if (!this.castleFlags[c][castleSide]) + continue; + // If this code is reached, rooks and king are on initial position + + // Nothing on the path of the king ? + // (And no checks; OK also if y==finalSquare) + let step = finalSquares[castleSide][0] < y ? -1 : 1; + for (i=y; i!=finalSquares[castleSide][0]; i+=step) + { + if (this.isAttacked([x,i], [oppCol]) || (this.board[x][i] != V.EMPTY && + // NOTE: next check is enough, because of chessboard constraints + (this.getColor(x,i) != c + || ![V.KING,V.ROOK].includes(this.getPiece(x,i))))) + { + continue castlingCheck; + } + } + + // Nothing on the path to the rook? + step = castleSide == 0 ? -1 : 1; + for (i = y + step; i != this.INIT_COL_ROOK[c][castleSide]; i += step) + { + if (this.board[x][i] != V.EMPTY) + continue castlingCheck; + } + const rookPos = this.INIT_COL_ROOK[c][castleSide]; + + // Nothing on final squares, except maybe king and castling rook? + for (i=0; i<2; i++) + { + if (this.board[x][finalSquares[castleSide][i]] != V.EMPTY && + this.getPiece(x,finalSquares[castleSide][i]) != V.KING && + finalSquares[castleSide][i] != rookPos) + { + continue castlingCheck; + } + } + + // If this code is reached, castle is valid + moves.push( new Move({ + appear: [ + new PiPo({x:x,y:finalSquares[castleSide][0],p:V.KING,c:c}), + new PiPo({x:x,y:finalSquares[castleSide][1],p:V.ROOK,c:c})], + vanish: [ + new PiPo({x:x,y:y,p:V.KING,c:c}), + new PiPo({x:x,y:rookPos,p:V.ROOK,c:c})], + end: Math.abs(y - rookPos) <= 2 + ? {x:x, y:rookPos} + : {x:x, y:y + 2 * (castleSide==0 ? -1 : 1)} + }) ); + } + + return moves; + } + + //////////////////// + // MOVES VALIDATION + + // For the interface: possible moves for the current turn from square sq + getPossibleMovesFrom(sq) + { + return this.filterValid( this.getPotentialMovesFrom(sq) ); + } + + // TODO: promotions (into R,B,N,Q) should be filtered only once + filterValid(moves) + { + if (moves.length == 0) + return []; + const color = this.turn; + return moves.filter(m => { + this.play(m); + const res = !this.underCheck(color); + this.undo(m); + return res; + }); + } + + // Search for all valid moves considering current turn + // (for engine and game end) + getAllValidMoves() + { + const color = this.turn; + const oppCol = V.GetOppCol(color); + let potentialMoves = []; + for (let i=0; i 0) + { + for (let k=0; k 0) + return true; + } + } + } + } + } + return false; + } + + // Check if pieces of color in 'colors' are attacking (king) on square x,y + isAttacked(sq, colors) + { + return (this.isAttackedByPawn(sq, colors) + || this.isAttackedByRook(sq, colors) + || this.isAttackedByKnight(sq, colors) + || this.isAttackedByBishop(sq, colors) + || this.isAttackedByQueen(sq, colors) + || this.isAttackedByKing(sq, colors)); + } + + // Is square x,y attacked by 'colors' pawns ? + isAttackedByPawn([x,y], colors) + { + for (let c of colors) + { + let pawnShift = (c=="w" ? 1 : -1); + if (x+pawnShift>=0 && x+pawnShift=0 && y+i= 1) + { + // Usual case, something is moved + piece = move.vanish[0].p; + c = move.vanish[0].c; + } + else + { + // Crazyhouse-like variants + piece = move.appear[0].p; + c = move.appear[0].c; + } + if (c == "c") //if (!["w","b"].includes(c)) + { + // 'c = move.vanish[0].c' doesn't work for Checkered + c = V.GetOppCol(this.turn); + } + const firstRank = (c == "w" ? V.size.x-1 : 0); + + // Update king position + flags + if (piece == V.KING && move.appear.length > 0) + { + this.kingPos[c][0] = move.appear[0].x; + this.kingPos[c][1] = move.appear[0].y; + if (V.HasFlags) + this.castleFlags[c] = [false,false]; + return; + } + if (V.HasFlags) + { + // Update castling flags if rooks are moved + const oppCol = V.GetOppCol(c); + const oppFirstRank = (V.size.x-1) - firstRank; + if (move.start.x == firstRank //our rook moves? + && this.INIT_COL_ROOK[c].includes(move.start.y)) + { + const flagIdx = (move.start.y == this.INIT_COL_ROOK[c][0] ? 0 : 1); + this.castleFlags[c][flagIdx] = false; + } + else if (move.end.x == oppFirstRank //we took opponent rook? + && this.INIT_COL_ROOK[oppCol].includes(move.end.y)) + { + const flagIdx = (move.end.y == this.INIT_COL_ROOK[oppCol][0] ? 0 : 1); + this.castleFlags[oppCol][flagIdx] = false; + } + } + } + + // After move is undo-ed *and flags resetted*, un-update other variables + // TODO: more symmetry, by storing flags increment in move (?!) + unupdateVariables(move) + { + // (Potentially) Reset king position + const c = this.getColor(move.start.x,move.start.y); + if (this.getPiece(move.start.x,move.start.y) == V.KING) + this.kingPos[c] = [move.start.x, move.start.y]; + } + + play(move) + { + // DEBUG: +// if (!this.states) this.states = []; +// const stateFen = this.getBaseFen() + this.getTurnFen() + this.getFlagsFen(); +// this.states.push(stateFen); + + if (V.HasFlags) + move.flags = JSON.stringify(this.aggregateFlags()); //save flags (for undo) + if (V.HasEnpassant) + this.epSquares.push( this.getEpSquare(move) ); + if (!move.color) + move.color = this.turn; //for interface + V.PlayOnBoard(this.board, move); + this.turn = V.GetOppCol(this.turn); + this.movesCount++; + this.updateVariables(move); + } + + undo(move) + { + if (V.HasEnpassant) + this.epSquares.pop(); + if (V.HasFlags) + this.disaggregateFlags(JSON.parse(move.flags)); + V.UndoOnBoard(this.board, move); + this.turn = V.GetOppCol(this.turn); + this.movesCount--; + this.unupdateVariables(move); + + // DEBUG: +// const stateFen = this.getBaseFen() + this.getTurnFen() + this.getFlagsFen(); +// if (stateFen != this.states[this.states.length-1]) debugger; +// this.states.pop(); + } + + /////////////// + // END OF GAME + + // What is the score ? (Interesting if game is over) + getCurrentScore() + { + if (this.atLeastOneMove()) // game not over + return "*"; + + // Game over + const color = this.turn; + // No valid move: stalemate or checkmate? + if (!this.isAttacked(this.kingPos[color], [V.GetOppCol(color)])) + return "1/2"; + // OK, checkmate + return (color == "w" ? "0-1" : "1-0"); + } + + /////////////// + // ENGINE PLAY + + // Pieces values + static get VALUES() + { + return { + 'p': 1, + 'r': 5, + 'n': 3, + 'b': 3, + 'q': 9, + 'k': 1000 + }; + } + + // "Checkmate" (unreachable eval) + static get INFINITY() { return 9999; } + + // At this value or above, the game is over + static get THRESHOLD_MATE() { return V.INFINITY; } + + // Search depth: 2 for high branching factor, 4 for small (Loser chess, eg.) + static get SEARCH_DEPTH() { return 3; } + + // Assumption: at least one legal move + // 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"); + + // 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 eval2)) + { + eval2 = evalPos; + } + this.undo(moves2[j]); + } + } + else + eval2 = (score1=="1/2" ? 0 : (score1=="1-0" ? 1 : -1) * maxeval); + if ((color=="w" && eval2 > moves1[i].eval) + || (color=="b" && eval2 < moves1[i].eval)) + { + moves1[i].eval = eval2; + } + this.undo(moves1[i]); + } + moves1.sort( (a,b) => { return (color=="w" ? 1 : -1) * (b.eval - a.eval); }); + + let candidates = [0]; //indices of candidates moves + for (let j=1; j= 3: may take a while, so we control time + const timeStart = Date.now(); + + // Skip depth 3+ if we found a checkmate (or if we are checkmated in 1...) + if (V.SEARCH_DEPTH >= 3 && Math.abs(moves1[0].eval) < V.THRESHOLD_MATE) + { + for (let i=0; i= 5000) //more than 5 seconds + return currentBest; //depth 2 at least + this.play(moves1[i]); + // 0.1 * oldEval : heuristic to avoid some bad moves (not all...) + moves1[i].eval = 0.1*moves1[i].eval + + this.alphabeta(V.SEARCH_DEPTH-1, -maxeval, maxeval); + this.undo(moves1[i]); + } + moves1.sort( (a,b) => { + return (color=="w" ? 1 : -1) * (b.eval - a.eval); }); + } + else + return currentBest; +// console.log(moves1.map(m => { return [this.getNotation(m), m.eval]; })); + + candidates = [0]; + for (let j=1; j= beta) + break; //beta cutoff + } + } + else //color=="b" + { + for (let i=0; i= beta) + break; //alpha cutoff + } + } + return v; + } + + evalPosition() + { + let evaluation = 0; + // Just count material for now + for (let i=0; i move.appear.length) { - this.play(moves[i]); - v = Math.max(v, this.alphabeta(depth-1, alpha, beta)); - this.undo(moves[i]); - alpha = Math.max(alpha, v); - if (alpha >= beta) - break; //beta cutoff - } - } - else //color=="b" - { - for (let i=0; i= beta) - break; //alpha cutoff - } - } - return v; - } - - evalPosition() - { - let evaluation = 0; - // Just count material for now - for (let i=0; i move.appear.length) - { - // Capture - const startColumn = V.CoordToColumn(move.start.y); - notation = startColumn + "x" + finalSquare; - } - else //no capture - notation = finalSquare; - if (move.appear.length > 0 && move.appear[0].p != V.PAWN) //promotion - notation += "=" + move.appear[0].p.toUpperCase(); - return notation; - } - - else - { - // Piece movement - return piece.toUpperCase() + - (move.vanish.length > move.appear.length ? "x" : "") + finalSquare; - } - } + // Capture + const startColumn = V.CoordToColumn(move.start.y); + notation = startColumn + "x" + finalSquare; + } + else //no capture + notation = finalSquare; + if (move.appear.length > 0 && move.appear[0].p != V.PAWN) //promotion + notation += "=" + move.appear[0].p.toUpperCase(); + return notation; + } + + else + { + // Piece movement + return piece.toUpperCase() + + (move.vanish.length > move.appear.length ? "x" : "") + finalSquare; + } + } } diff --git a/client/src/components/ComputerGame.vue b/client/src/components/ComputerGame.vue index b3db07f9..2070cd09 100644 --- a/client/src/components/ComputerGame.vue +++ b/client/src/components/ComputerGame.vue @@ -75,6 +75,7 @@ export default { const vModule = await import("@/variants/" + this.vname + ".js"); window.V = vModule.VariantRules; this.compWorker.postMessage(["scripts",this.vname]); + this.compWorker.postMessage(["init",this.fen]); this.newGameFromFen(this.fen); }, newGameFromFen: function(fen) { @@ -93,7 +94,7 @@ export default { this.mycolor = (Math.random() < 0.5 ? "w" : "b"); this.orientation = this.mycolor; this.compWorker.postMessage(["init",fen]); - if (this.mycolor != "w" || this.subMode == "auto") + if (this.mycolor != "w" || this.mode == "auto") this.playComputerMove(); } }, diff --git a/client/src/playCompMove.js b/client/src/playCompMove.js index ddaeba38..062eae35 100644 --- a/client/src/playCompMove.js +++ b/client/src/playCompMove.js @@ -5,22 +5,22 @@ //self.addEventListener('message', (e) => onmessage = async function(e) { - switch (e.data[0]) - { - case "scripts": + switch (e.data[0]) + { + case "scripts": const vModule = await import("@/variants/" + e.data[1] + ".js"); - self.V = vModule.VariantRules; - break; - case "init": - const fen = e.data[1]; - self.vr = new self.V(fen); - break; - case "newmove": - self.vr.play(e.data[1]); - break; - case "askmove": - const compMove = self.vr.getComputerMove(); - postMessage(compMove); - break; - } + self.V = vModule.VariantRules; + break; + case "init": + const fen = e.data[1]; + self.vr = new self.V(fen); + break; + case "newmove": + self.vr.play(e.data[1]); + break; + case "askmove": + const compMove = self.vr.getComputerMove(); + postMessage(compMove); + break; + } } diff --git a/client/src/variants/Alice.js b/client/src/variants/Alice.js index 2feb8b8f..e80e13b6 100644 --- a/client/src/variants/Alice.js +++ b/client/src/variants/Alice.js @@ -2,6 +2,7 @@ import { ChessRules } from "@/base_rules"; import { ArrayFun} from "@/utils/array"; // NOTE: alternative implementation, probably cleaner = use only 1 board +// TODO? atLeastOneMove() would be more efficient if rewritten here (less sideBoard computations) export const VariantRules = class AliceRules extends ChessRules { static get ALICE_PIECES() @@ -98,12 +99,14 @@ export const VariantRules = class AliceRules extends ChessRules const pieces = Object.keys(V.ALICE_CODES); const codes = Object.keys(V.ALICE_PIECES); const mirrorSide = (pieces.includes(this.getPiece(x,y)) ? 1 : 2); + if (!sideBoard) + sideBoard = [this.getSideBoard(1), this.getSideBoard(2)]; const color = this.getColor(x,y); // Search valid moves on sideBoard - let saveBoard = this.board; - this.board = sideBoard || this.getSideBoard(mirrorSide); - let moves = super.getPotentialMovesFrom([x,y]) + const saveBoard = this.board; + this.board = sideBoard[mirrorSide-1]; + const moves = super.getPotentialMovesFrom([x,y]) .filter(m => { // Filter out king moves which result in under-check position on // current board (before mirror traversing) @@ -111,7 +114,7 @@ export const VariantRules = class AliceRules extends ChessRules if (m.appear[0].p == V.KING) { this.play(m); - if (this.underCheck(color)) + if (this.underCheck(color, sideBoard)) aprioriValid = false; this.undo(m); } @@ -120,7 +123,7 @@ export const VariantRules = class AliceRules extends ChessRules this.board = saveBoard; // Finally filter impossible moves - let res = moves.filter(m => { + const res = moves.filter(m => { if (m.appear.length == 2) //castle { // appear[i] must be an empty square on the other board @@ -172,11 +175,12 @@ export const VariantRules = class AliceRules extends ChessRules return res; } - filterValid(moves) + filterValid(moves, sideBoard) { if (moves.length == 0) return []; - let sideBoard = [this.getSideBoard(1), this.getSideBoard(2)]; + if (!sideBoard) + sideBoard = [this.getSideBoard(1), this.getSideBoard(2)]; const color = this.turn; return moves.filter(m => { this.playSide(m, sideBoard); //no need to track flags @@ -190,20 +194,16 @@ export const VariantRules = class AliceRules extends ChessRules { const color = this.turn; const oppCol = V.GetOppCol(color); - var potentialMoves = []; - let sideBoard = [this.getSideBoard(1), this.getSideBoard(2)]; + let potentialMoves = []; + const sideBoard = [this.getSideBoard(1), this.getSideBoard(2)]; for (var i=0; i