-\r
-// attack.c\r
-\r
-// includes\r
-\r
-#include "board.h"\r
-#include "colour.h"\r
-#include "move.h"\r
-#include "attack.h"\r
-#include "piece.h"\r
-#include "util.h"\r
-\r
-// macros\r
-\r
-#define DELTA_INC(delta) (DeltaInc[128+(delta)])\r
-#define DELTA_MASK(delta) (DeltaMask[128+(delta)])\r
-\r
-// "constants"\r
-\r
-const sint8 KnightInc[8+1] = {\r
- -33, -31, -18, -14, +14, +18, +31, +33, 0\r
-};\r
-\r
-const sint8 BishopInc[4+1] = {\r
- -17, -15, +15, +17, 0\r
-};\r
-\r
-const sint8 RookInc[4+1] = {\r
- -16, -1, +1, +16, 0\r
-};\r
-\r
-const sint8 QueenInc[8+1] = {\r
- -17, -16, -15, -1, +1, +15, +16, +17, 0\r
-};\r
-\r
-const sint8 KingInc[8+1] = {\r
- -17, -16, -15, -1, +1, +15, +16, +17, 0\r
-};\r
-\r
-// variables\r
-\r
-static sint8 DeltaInc[256];\r
-static uint8 DeltaMask[256];\r
-\r
-// prototypes\r
-\r
-static bool delta_is_ok (int delta);\r
-static bool inc_is_ok (int inc);\r
-\r
-// functions\r
-\r
-// attack_init()\r
-\r
-void attack_init() {\r
-\r
- int delta;\r
- int dir, inc, dist;\r
-\r
- for (delta = -128; delta < +128; delta++) {\r
- DeltaInc[128+delta] = IncNone;\r
- DeltaMask[128+delta] = 0;\r
- }\r
-\r
- DeltaMask[128-17] |= BlackPawnFlag;\r
- DeltaMask[128-15] |= BlackPawnFlag;\r
-\r
- DeltaMask[128+15] |= WhitePawnFlag;\r
- DeltaMask[128+17] |= WhitePawnFlag;\r
-\r
- for (dir = 0; dir < 8; dir++) {\r
- delta = KnightInc[dir];\r
- ASSERT(delta_is_ok(delta));\r
- DeltaMask[128+delta] |= KnightFlag;\r
- }\r
-\r
- for (dir = 0; dir < 4; dir++) {\r
- inc = BishopInc[dir];\r
- ASSERT(inc!=IncNone);\r
- for (dist = 1; dist < 8; dist++) {\r
- delta = inc*dist;\r
- ASSERT(delta_is_ok(delta));\r
- ASSERT(DeltaInc[128+delta]==IncNone);\r
- DeltaInc[128+delta] = inc;\r
- DeltaMask[128+delta] |= BishopFlag;\r
- }\r
- }\r
-\r
- for (dir = 0; dir < 4; dir++) {\r
- inc = RookInc[dir];\r
- ASSERT(inc!=IncNone);\r
- for (dist = 1; dist < 8; dist++) {\r
- delta = inc*dist;\r
- ASSERT(delta_is_ok(delta));\r
- ASSERT(DeltaInc[128+delta]==IncNone);\r
- DeltaInc[128+delta] = inc;\r
- DeltaMask[128+delta] |= RookFlag;\r
- }\r
- }\r
-\r
- for (dir = 0; dir < 8; dir++) {\r
- delta = KingInc[dir];\r
- ASSERT(delta_is_ok(delta));\r
- DeltaMask[128+delta] |= KingFlag;\r
- }\r
-}\r
-\r
-// delta_is_ok()\r
-\r
-static bool delta_is_ok(int delta) {\r
-\r
- if (delta < -119 || delta > +119) return FALSE;\r
-\r
- return TRUE;\r
-}\r
-\r
-// inc_is_ok()\r
-\r
-static bool inc_is_ok(int inc) {\r
-\r
- int dir;\r
-\r
- for (dir = 0; dir < 8; dir++) {\r
- if (KingInc[dir] == inc) return TRUE;\r
- }\r
-\r
- return FALSE;\r
-}\r
-\r
-// is_in_check()\r
-\r
-bool is_in_check(const board_t * board, int colour) {\r
-\r
- ASSERT(board_is_ok(board));\r
- ASSERT(colour_is_ok(colour));\r
-\r
- return is_attacked(board,king_pos(board,colour),colour_opp(colour));\r
-}\r
-\r
-// is_attacked()\r
-\r
-bool is_attacked(const board_t * board, int to, int colour) {\r
-\r
- const uint8 * ptr;\r
- int from, piece;\r
-\r
- ASSERT(board_is_ok(board));\r
- ASSERT(square_is_ok(to));\r
- ASSERT(colour_is_ok(colour));\r
-\r
- for (ptr = board->list[colour]; (from=*ptr) != SquareNone; ptr++) {\r
-\r
- piece = board->square[from];\r
- ASSERT(colour_equal(piece,colour));\r
-\r
- if (piece_attack(board,piece,from,to)) return TRUE;\r
- }\r
-\r
- return FALSE;\r
-}\r
-\r
-// piece_attack()\r
-\r
-bool piece_attack(const board_t * board, int piece, int from, int to) {\r
-\r
- int delta;\r
- int inc, sq;\r
-\r
- ASSERT(board_is_ok(board));\r
- ASSERT(piece_is_ok(piece));\r
- ASSERT(square_is_ok(from));\r
- ASSERT(square_is_ok(to));\r
-\r
- delta = to - from;\r
- ASSERT(delta_is_ok(delta));\r
-\r
- if ((piece & DELTA_MASK(delta)) == 0) return FALSE; // no pseudo-attack\r
-\r
- if (!piece_is_slider(piece)) return TRUE;\r
-\r
- inc = DELTA_INC(delta);\r
- ASSERT(inc_is_ok(inc));\r
-\r
- for (sq = from+inc; sq != to; sq += inc) {\r
- ASSERT(square_is_ok(sq));\r
- if (board->square[sq] != Empty) return FALSE; // blocker\r
- }\r
-\r
- return TRUE;\r
-}\r
-\r
-// is_pinned()\r
-\r
-bool is_pinned(const board_t * board, int from, int to, int colour) {\r
-\r
- int king;\r
- int inc;\r
- int sq, piece;\r
-\r
- ASSERT(board!=NULL);\r
- ASSERT(square_is_ok(from));\r
- ASSERT(square_is_ok(to));\r
- ASSERT(colour_is_ok(colour));\r
-\r
- king = king_pos(board,colour);\r
-\r
- inc = DELTA_INC(king-from);\r
- if (inc == IncNone) return FALSE; // not a line\r
-\r
- sq = from;\r
- do sq += inc; while (board->square[sq] == Empty);\r
-\r
- if (sq != king) return FALSE; // blocker\r
-\r
- sq = from;\r
- do sq -= inc; while ((piece=board->square[sq]) == Empty);\r
-\r
- return square_is_ok(sq)\r
- && (piece & DELTA_MASK(king-sq)) != 0\r
- && piece_colour(piece) == colour_opp(colour)\r
- && DELTA_INC(king-to) != inc;\r
-}\r
-\r
-// end of attack.cpp\r
-\r
+
+// attack.c
+
+// includes
+
+#include "board.h"
+#include "colour.h"
+#include "move.h"
+#include "attack.h"
+#include "piece.h"
+#include "util.h"
+
+// macros
+
+#define DELTA_INC(delta) (DeltaInc[128+(delta)])
+#define DELTA_MASK(delta) (DeltaMask[128+(delta)])
+
+// "constants"
+
+const sint8 KnightInc[8+1] = {
+ -33, -31, -18, -14, +14, +18, +31, +33, 0
+};
+
+const sint8 BishopInc[4+1] = {
+ -17, -15, +15, +17, 0
+};
+
+const sint8 RookInc[4+1] = {
+ -16, -1, +1, +16, 0
+};
+
+const sint8 QueenInc[8+1] = {
+ -17, -16, -15, -1, +1, +15, +16, +17, 0
+};
+
+const sint8 KingInc[8+1] = {
+ -17, -16, -15, -1, +1, +15, +16, +17, 0
+};
+
+// variables
+
+static sint8 DeltaInc[256];
+static uint8 DeltaMask[256];
+
+// prototypes
+
+static bool delta_is_ok (int delta);
+static bool inc_is_ok (int inc);
+
+// functions
+
+// attack_init()
+
+void attack_init() {
+
+ int delta;
+ int dir, inc, dist;
+
+ for (delta = -128; delta < +128; delta++) {
+ DeltaInc[128+delta] = IncNone;
+ DeltaMask[128+delta] = 0;
+ }
+
+ DeltaMask[128-17] |= BlackPawnFlag;
+ DeltaMask[128-15] |= BlackPawnFlag;
+
+ DeltaMask[128+15] |= WhitePawnFlag;
+ DeltaMask[128+17] |= WhitePawnFlag;
+
+ for (dir = 0; dir < 8; dir++) {
+ delta = KnightInc[dir];
+ ASSERT(delta_is_ok(delta));
+ DeltaMask[128+delta] |= KnightFlag;
+ }
+
+ for (dir = 0; dir < 4; dir++) {
+ inc = BishopInc[dir];
+ ASSERT(inc!=IncNone);
+ for (dist = 1; dist < 8; dist++) {
+ delta = inc*dist;
+ ASSERT(delta_is_ok(delta));
+ ASSERT(DeltaInc[128+delta]==IncNone);
+ DeltaInc[128+delta] = inc;
+ DeltaMask[128+delta] |= BishopFlag;
+ }
+ }
+
+ for (dir = 0; dir < 4; dir++) {
+ inc = RookInc[dir];
+ ASSERT(inc!=IncNone);
+ for (dist = 1; dist < 8; dist++) {
+ delta = inc*dist;
+ ASSERT(delta_is_ok(delta));
+ ASSERT(DeltaInc[128+delta]==IncNone);
+ DeltaInc[128+delta] = inc;
+ DeltaMask[128+delta] |= RookFlag;
+ }
+ }
+
+ for (dir = 0; dir < 8; dir++) {
+ delta = KingInc[dir];
+ ASSERT(delta_is_ok(delta));
+ DeltaMask[128+delta] |= KingFlag;
+ }
+}
+
+// delta_is_ok()
+
+static bool delta_is_ok(int delta) {
+
+ if (delta < -119 || delta > +119) return FALSE;
+
+ return TRUE;
+}
+
+// inc_is_ok()
+
+static bool inc_is_ok(int inc) {
+
+ int dir;
+
+ for (dir = 0; dir < 8; dir++) {
+ if (KingInc[dir] == inc) return TRUE;
+ }
+
+ return FALSE;
+}
+
+// is_in_check()
+
+bool is_in_check(const board_t * board, int colour) {
+
+ ASSERT(board_is_ok(board));
+ ASSERT(colour_is_ok(colour));
+
+ return is_attacked(board,king_pos(board,colour),colour_opp(colour));
+}
+
+// is_attacked()
+
+bool is_attacked(const board_t * board, int to, int colour) {
+
+ const uint8 * ptr;
+ int from, piece;
+
+ ASSERT(board_is_ok(board));
+ ASSERT(square_is_ok(to));
+ ASSERT(colour_is_ok(colour));
+
+ for (ptr = board->list[colour]; (from=*ptr) != SquareNone; ptr++) {
+
+ piece = board->square[from];
+ ASSERT(colour_equal(piece,colour));
+
+ if (piece_attack(board,piece,from,to)) return TRUE;
+ }
+
+ return FALSE;
+}
+
+// piece_attack()
+
+bool piece_attack(const board_t * board, int piece, int from, int to) {
+
+ int delta;
+ int inc, sq;
+
+ ASSERT(board_is_ok(board));
+ ASSERT(piece_is_ok(piece));
+ ASSERT(square_is_ok(from));
+ ASSERT(square_is_ok(to));
+
+ delta = to - from;
+ ASSERT(delta_is_ok(delta));
+
+ if ((piece & DELTA_MASK(delta)) == 0) return FALSE; // no pseudo-attack
+
+ if (!piece_is_slider(piece)) return TRUE;
+
+ inc = DELTA_INC(delta);
+ ASSERT(inc_is_ok(inc));
+
+ for (sq = from+inc; sq != to; sq += inc) {
+ ASSERT(square_is_ok(sq));
+ if (board->square[sq] != Empty) return FALSE; // blocker
+ }
+
+ return TRUE;
+}
+
+// is_pinned()
+
+bool is_pinned(const board_t * board, int from, int to, int colour) {
+
+ int king;
+ int inc;
+ int sq, piece;
+
+ ASSERT(board!=NULL);
+ ASSERT(square_is_ok(from));
+ ASSERT(square_is_ok(to));
+ ASSERT(colour_is_ok(colour));
+
+ king = king_pos(board,colour);
+
+ inc = DELTA_INC(king-from);
+ if (inc == IncNone) return FALSE; // not a line
+
+ sq = from;
+ do sq += inc; while (board->square[sq] == Empty);
+
+ if (sq != king) return FALSE; // blocker
+
+ sq = from;
+ do sq -= inc; while ((piece=board->square[sq]) == Empty);
+
+ return square_is_ok(sq)
+ && (piece & DELTA_MASK(king-sq)) != 0
+ && piece_colour(piece) == colour_opp(colour)
+ && DELTA_INC(king-to) != inc;
+}
+
+// end of attack.cpp
+