src/piece.h

   1 /* Copyright (C) 2007-2012 Vincent Ollivier
   2  *
   3  * Purple Haze is free software: you can redistribute it and/or modify
   4  * it under the terms of the GNU General Public License as published by
   5  * the Free Software Foundation, either version 3 of the License, or
   6  * (at your option) any later version.
   7  *
   8  * Purple Haze is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License
  14  * along with this program. If not, see <http://www.gnu.org/licenses/>.
  15  */
  16
  17 #ifndef PIECE_H
  18 #define PIECE_H
  19
  20 #include <string>
  21
  22 #include "common.h"
  23
  24 class Piece
  25 {
  26     private:
  27         /*
  28          * A piece is coded using 8 bits:
  29          *     1 bit for the color
  30          *     3 bits for the type
  31          *     4 bits for the index in pieces[c][t][i]
  32          *
  33          * FIXME? No warning given if index is > 4 bits
  34          */
  35         static const int C_MASK = 0x1;
  36         static const int T_MASK = 0x7;
  37         static const int I_MASK = 0xF;
  38         static const int C_SHIFT = 0;
  39         static const int T_SHIFT = 1;
  40         static const int I_SHIFT = 4;
  41
  42         unsigned char code;
  43
  44     public:
  45         Piece() : code(EMPTY) {}
  46
  47         Piece(Color c, PieceType t, int i = 0) {
  48             code = (i << I_SHIFT) |
  49                    (static_cast<int>(t) << T_SHIFT) |
  50                    (static_cast<int>(c) << C_SHIFT);
  51         }
  52
  53         Color color() const {
  54             return static_cast<Color>((code >> C_SHIFT) & C_MASK);
  55         };
  56         PieceType type() const {
  57             return static_cast<PieceType>((code >> T_SHIFT) & T_MASK);
  58         };
  59         int index() const {
  60             return (code >> I_SHIFT) & I_MASK;
  61         };
  62         /*
  63         void set_index(int i) {
  64             code &= I_MASK;
  65             code |= (i << I_SHIFT);
  66         }
  67         */
  68         bool is(const Color c) const {
  69             return color() == c;
  70         }
  71         bool is(const PieceType t) const {
  72             return type() == t;
  73         }
  74         bool is(const Color c, const PieceType t) const {
  75             return is(c) && is(t);
  76         }
  77         bool operator==(const Piece& other) const {
  78             return this->code == other.code;
  79         }
  80         bool operator!=(const Piece& other) const {
  81             return !(*this == other);
  82         }
  83         std::string to_string() const;
  84
  85         friend std::ostream& operator<<(std::ostream& out, const Piece piece);
  86 };
  87
  88 #endif /* !PIECE_H */