Mercurial > hg > terminal-chess / file comparison
comparison: src/chess/king.c
src/chess/king.c
- changeset 216
- d0c3d3016650
- parent 195
- 27d02ccb0cef
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| 215:d20887f0e8b3 | 216:d0c3d3016650 |
|---|---|
| 28 */ | 28 */ |
| 29 | 29 |
| 30 #include "rules.h" | 30 #include "rules.h" |
| 31 #include "king.h" | 31 #include "king.h" |
| 32 | 32 |
| 33 static bool king_castling_chkmoved( | |
| 34 const GameState *gamestate, File file, Rank rank) { | |
| 35 | |
| 36 for (unsigned i = 0; i < gamestate->movecount; i++) { | |
| 37 if (gamestate->moves[i].fromfile == file | |
| 38 && gamestate->moves[i].fromrank == rank) { | |
| 39 return true; | |
| 40 } | |
| 41 } | |
| 42 | |
| 43 return false; | |
| 44 } | |
| 45 | |
| 46 bool king_chkrules(const GameState *gamestate, const Move* move) { | 33 bool king_chkrules(const GameState *gamestate, const Move* move) { |
| 47 if (abs(move->torank - move->fromrank) <= 1 && | 34 if (abs(move->torank - move->fromrank) <= 1 && |
| 48 abs(move->tofile - move->fromfile) <= 1) { | 35 abs(move->tofile - move->fromfile) <= 1) { |
| 49 return true; | 36 return true; |
| 37 } else if (move->fromrank == move->torank) { | |
| 38 /* castling */ | |
| 39 Rank backrank; | |
| 40 bool k_allowed, q_allowed; | |
| 41 if (piece_color(move->piece) == WHITE) { | |
| 42 backrank = rankidx('1'); | |
| 43 k_allowed = !gamestate->castling.K; | |
| 44 q_allowed = !gamestate->castling.Q; | |
| 45 } else { | |
| 46 backrank = rankidx('8'); | |
| 47 k_allowed = !gamestate->castling.k; | |
| 48 q_allowed = !gamestate->castling.q; | |
| 49 } | |
| 50 bool castle_q = false, castle_k = false; | |
| 51 if (move->fromrank == backrank && move->fromfile == fileidx('e')) { | |
| 52 castle_q = move->tofile == fileidx('c'); | |
| 53 castle_k = move->tofile == fileidx('g'); | |
| 54 } | |
| 55 /* note that here we do not consider threats! | |
| 56 * that is what king_isblocked() does */ | |
| 57 return (castle_q && q_allowed) || (castle_k && k_allowed); | |
| 50 } else { | 58 } else { |
| 51 /* castling */ | 59 return false; |
| 52 if (move->fromrank == move->torank && | |
| 53 move->fromrank == (piece_color(move->piece) == WHITE ? 0 : 7) && | |
| 54 move->fromfile == fileidx('e') && | |
| 55 (move->tofile == fileidx('c') || move->tofile == fileidx('g'))) { | |
| 56 | |
| 57 return !king_castling_chkmoved(gamestate, | |
| 58 move->fromfile, move->fromrank) && | |
| 59 !king_castling_chkmoved(gamestate, | |
| 60 move->tofile == fileidx('c') ? 0 : 7, move->fromrank); | |
| 61 } else { | |
| 62 return false; | |
| 63 } | |
| 64 } | 60 } |
| 65 } | 61 } |
| 66 | 62 |
| 67 bool king_isblocked(const GameState *gamestate, const Move *move) { | 63 bool king_isblocked(const GameState *gamestate, const Move *move) { |
| 68 | |
| 69 Color op_color = opponent_color(piece_color(move->piece)); | |
| 70 | |
| 71 /* being in check does not "block" the king, so don't test it here */ | |
| 72 bool blocked = false; | |
| 73 | |
| 74 /* just test, if castling move is blocked */ | 64 /* just test, if castling move is blocked */ |
| 75 if (abs(move->tofile - move->fromfile) == 2) { | 65 if (abs(move->tofile - move->fromfile) == 2) { |
| 76 if (move->tofile == fileidx('c')) { | 66 if (move->tofile == fileidx('c')) { |
| 77 blocked |= gamestate->board[move->torank][fileidx('b')]; | 67 /* check if rook can travel the queen-side */ |
| 68 if (gamestate->board[move->torank][fileidx('b')]) { | |
| 69 return true; | |
| 70 } | |
| 78 } | 71 } |
| 72 /* check if new field for the rook is free */ | |
| 79 File midfile = (move->tofile+move->fromfile)/2; | 73 File midfile = (move->tofile+move->fromfile)/2; |
| 80 bool incheck = false; | 74 if (gamestate->board[move->torank][midfile]) { |
| 81 if (gamestate->movecount > 0) { | 75 return true; |
| 82 incheck = is_check_position(gamestate); | |
| 83 } | 76 } |
| 84 blocked |= incheck || gamestate->board[move->torank][midfile] || | 77 /* check if the king or the target field for the rook is threatened */ |
| 85 is_covered(gamestate, midfile, move->torank, op_color); | 78 if (is_check_position(gamestate) || is_covered(gamestate, |
| 79 midfile, move->torank, opponent_color(piece_color(move->piece)))) { | |
| 80 return true; | |
| 81 } | |
| 86 } | 82 } |
| 87 | 83 return false; |
| 88 return blocked; | |
| 89 } | 84 } |
| 90 | 85 |
| 91 size_t king_moves(const GameState *gamestate, | 86 size_t king_moves(const GameState *gamestate, |
| 92 Color c, File f, Rank r, Move *moves) { | 87 Color c, File f, Rank r, Move *moves) { |
| 93 | 88 |
