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author | toma <toma@283d02a7-25f6-0310-bc7c-ecb5cbfe19da> | 2009-11-25 17:56:58 +0000 |
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committer | toma <toma@283d02a7-25f6-0310-bc7c-ecb5cbfe19da> | 2009-11-25 17:56:58 +0000 |
commit | c90c389a8a8d9d8661e9772ec4144c5cf2039f23 (patch) | |
tree | 6d8391395bce9eaea4ad78958617edb20c6a7573 /kreversi/Position.cpp | |
download | tdegames-c90c389a8a8d9d8661e9772ec4144c5cf2039f23.tar.gz tdegames-c90c389a8a8d9d8661e9772ec4144c5cf2039f23.zip |
Copy the KDE 3.5 branch to branches/trinity for new KDE 3.5 features.
BUG:215923
git-svn-id: svn://anonsvn.kde.org/home/kde/branches/trinity/kdegames@1054174 283d02a7-25f6-0310-bc7c-ecb5cbfe19da
Diffstat (limited to 'kreversi/Position.cpp')
-rw-r--r-- | kreversi/Position.cpp | 366 |
1 files changed, 366 insertions, 0 deletions
diff --git a/kreversi/Position.cpp b/kreversi/Position.cpp new file mode 100644 index 00000000..22ffb3cf --- /dev/null +++ b/kreversi/Position.cpp @@ -0,0 +1,366 @@ +/* Yo Emacs, this -*- C++ -*- + ******************************************************************* + ******************************************************************* + * + * + * KREVERSI + * + * + ******************************************************************* + * + * A Reversi (or sometimes called Othello) game + * + ******************************************************************* + * + * Created 1997 by Mario Weilguni <[email protected]>. This file + * is ported from Mats Luthman's <[email protected]> JAVA applet. + * Many thanks to Mr. Luthman who has allowed me to put this port + * under the GNU GPL. Without his wonderful game engine kreversi + * would be just another of those Reversi programs a five year old + * child could beat easily. But with it it's a worthy opponent! + * + * If you are interested on the JAVA applet of Mr. Luthman take a + * look at http://www.sylog.se/~mats/ + * + ******************************************************************* + * + * This file is part of the KDE project "KREVERSI" + * + * KREVERSI is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2, or (at your option) + * any later version. + * + * KREVERSI is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with KREVERSI; see the file COPYING. If not, write to + * the Free Software Foundation, 51 Franklin Street, Fifth Floor, + * Boston, MA 02110-1301, USA. + * + ******************************************************************* + */ + +// The class Position is used to represent an Othello position as white and +// black pieces and empty squares (see class Score) on an 8x8 Othello board. + + +#include "kdebug.h" + +#include "Position.h" +#include <stdlib.h> + + +Position::Position() +{ + setupStartPosition(); +} + + +Position::Position(Position &pos, SimpleMove &move) +{ + constrCopy(pos, move); +} + + +Position &Position::operator=(Position &pos) +{ + // Copy the position itself. + for (uint row = 0; row < 10; row++) + for (uint col = 0; col < 10; col++) + m_board[row][col] = pos.m_board[row][col]; + m_toMove = pos.m_toMove; + + m_score = pos.m_score; + + return *this; +} + + +// ---------------------------------------------------------------- +// Helpers to the constructors + + +// Construct a Position by copying another one and then make a move. +// + +void Position::constrCopy(Position &pos, SimpleMove &move) +{ + *this = pos; + doMove(move); +} + + +// Setup the Position by setting it to the initial Reversi position. + +void Position::setupStartPosition() +{ + // Initialize the real board + for (uint i = 0; i < 10; i++) + for (uint j = 0; j < 10; j++) + m_board[i][j] = Nobody; + + // The initial position + m_board[4][4] = White; + m_board[5][5] = White; + m_board[5][4] = Black; + m_board[4][5] = Black; + + // Black always starts the game in Reversi. + m_toMove = Black; + + // Each side starts out with two pieces. + m_score.set(White, 2); + m_score.set(Black, 2); +} + + +// ---------------------------------------------------------------- +// Access methods + + +Color Position::color(uint x, uint y) const +{ + if (x < 1 || x > 8 || y < 1 || y > 8) + return Nobody; + + return m_board[x][y]; +} + + +// ---------------------------------------------------------------- +// Moves in the position + + +// Return true if the move is legal. +// +// NOTE: This function does *NOT* test wether the move is done +// by the color to move. That must be checked separately. +// + +bool Position::moveIsLegal(SimpleMove &move) const +{ + if (m_board[move.x()][move.y()] != Nobody) + return false; + + Color color = move.color(); + Color opponent = ::opponent(color); + + // Check in all directions and see if there is a turnable row of + // opponent pieces. If there is at least one such row, then the + // move is legal. + for (int xinc = -1; xinc <= 1; xinc++) { + for (int yinc = -1; yinc <= 1; yinc++) { + int x, y; + + if (xinc == 0 && yinc == 0) + continue; + + // Find the end of such a row of pieces. + for (x = move.x()+xinc, y = move.y()+yinc; m_board[x][y] == opponent; + x += xinc, y += yinc) + ; + + // If the row ends with a piece of our own and there was at + // least one opponent piece between it and the move point, then + // we have found a turnable row. + if (m_board[x][y] == color + && (x - xinc != move.x() || y - yinc != move.y())) + return true; + } + } + + return false; +} + + +// See if 'color' can make a move in the current position. This is +// independent of wether it is 'color's turn to move or not. + +bool Position::moveIsPossible(Color color) const +{ + // Make it simple: Step through all squares and see if it is a legal move. + for (uint i = 1; i < 9; i++) + for (uint j = 1; j < 9; j++) { + SimpleMove move(color, i, j); + + if (moveIsLegal(move)) + return true; + } + + return false; +} + + +// Return true if any side can move. (If not, the game is over.) + +bool Position::moveIsAtAllPossible() const +{ + return (moveIsPossible(White) || moveIsPossible(Black)); +} + + +// Make a move in the position. +// +// Return true if the move was legal, otherwise return false. +// +bool Position::doMove(SimpleMove &move, QValueList<char> *turned) +{ + if (move.color() == Nobody) + return false; + + Color color = move.color(); + Color opponent = ::opponent(color); + + // Put the piece on the board + m_board[move.x()][move.y()] = color; + m_score.inc(color); + + // Turn pieces. + uint scoreBefore = m_score.score(color); + for (int xinc = -1; xinc <= 1; xinc++) { + for (int yinc = -1; yinc <= 1; yinc++) { + int x, y; + + // Skip the case where both xinc and yinc == 0, since then we + // won't move in any direction at all. + if (xinc == 0 && yinc == 0) + continue; + + // Find the end point (x, y) of a possible row of turnable pieces. + for (x = move.x()+xinc, y = move.y()+yinc; m_board[x][y] == opponent; + x += xinc, y += yinc) + ; + + // If the row was indeed turnable, then do it. + if (m_board[x][y] == color) { + for (x -= xinc, y -= yinc; x != move.x() || y != move.y(); + x -= xinc, y -= yinc) { + // Turn the piece. + m_board[x][y] = color; + if (turned) + turned->append(10 * x + y); + + // Make the piece count correct again. + m_score.inc(color); + m_score.dec(opponent); + } + } + } + } + + // If nothing was turned, the move wasn't legal. + if (m_score.score(color) == scoreBefore) { + m_board[move.x()][move.y()] = Nobody; + m_score.dec(color); + + return false; + } + + // Set the next color to move. + if (moveIsPossible(opponent)) + m_toMove = opponent; + else if (moveIsPossible(color)) + m_toMove = color; + else + m_toMove = Nobody; + + return true; +} + + +bool Position::doMove(Move &move) +{ + move.m_turnedPieces.clear(); + return doMove((SimpleMove &) move, &move.m_turnedPieces); +} + + +bool Position::undoMove(Move &move) +{ + Color color = move.color(); + Color other = opponent(color); + + // Sanity checks + // 1. The move must be on the board and be of the right color. + if (color != m_board[move.x()][move.y()]) { + //kdDebug() << "move on the board is wrong color: " << (int) color << "[" + // << move.x() << "," << move.y() << "]" << endl; + return false; + } + + // 2. All turned pieces must be on the board anb be of the right color. + QValueList<char>::iterator it; + for (it = move.m_turnedPieces.begin(); + it != move.m_turnedPieces.end(); + ++it) { + int sq = *it; + + if (m_board[sq / 10][sq % 10] != color) { + //kdDebug() << "turned piece the board is wrong color: [" + // << sq / 10 << "," << sq % 10 << "]" << endl; + return false; + } + } + + // Ok, everything seems allright. Let's do it! + // 1. Unturn all the turned pieces. + for (it = move.m_turnedPieces.begin(); + it != move.m_turnedPieces.end(); + ++it) { + int sq = *it; + + m_board[sq / 10][sq % 10] = other; + m_score.dec(color); + m_score.inc(other); + } + + // 2. Remove the move itself. + m_score.dec(color); + m_board[move.x()][move.y()] = Nobody; + + + return true; +} + + +MoveList Position::generateMoves(Color color) const +{ + MoveList moves; + + // Make it simple: Step through all squares and see if it is a legal move. + for (uint i = 1; i < 9; i++) { + for (uint j = 1; j < 9; j++) { + Move move(color, i, j); + + if (moveIsLegal(move)) + moves.append(move); + } + } + + return moves; +} + + +QString Position::asString() const +{ + QString result; + + for (uint y = 1; y < 9; ++y) { + for (uint x = 1; x < 9; ++x) { + switch (m_board[x][y]) { + case Nobody: result.append(' '); break; + case Black: result.append('*'); break; + case White: result.append('o'); break; + default: result.append('?'); break; + } + } + + result.append('\n'); + } + + return result; +} |