X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fsquare.h;h=621e398fb19069180f141df29423c4af171de2b6;hp=88ae1363a6943263ead7095487f78b745f35a798;hb=6080fecf9cba9ac063f8f07bd25004c14016bd33;hpb=94a67c49b0238200bbd4b167d067f067ff4aad30

diff --git a/src/square.h b/src/square.h
index 88ae1363..621e398f 100644
--- a/src/square.h
+++ b/src/square.h
@@ -68,10 +68,23 @@ enum SquareDelta {
   DELTA_NW = DELTA_N + DELTA_W,
 };
 
+enum Direction {
+  DIR_E = 0, DIR_N = 1, DIR_NE = 2, DIR_NW = 3, DIR_NONE = 4
+};
+
+enum SignedDirection {
+  SIGNED_DIR_E  = 0, SIGNED_DIR_W  = 1,
+  SIGNED_DIR_N  = 2, SIGNED_DIR_S  = 3,
+  SIGNED_DIR_NE = 4, SIGNED_DIR_SW = 5,
+  SIGNED_DIR_NW = 6, SIGNED_DIR_SE = 7,
+  SIGNED_DIR_NONE = 8
+};
+
 ENABLE_OPERATORS_ON(Square);
 ENABLE_OPERATORS_ON(File);
 ENABLE_OPERATORS_ON(Rank);
 ENABLE_OPERATORS_ON(SquareDelta);
+ENABLE_OPERATORS_ON(SignedDirection);
 
 
 ////
@@ -81,6 +94,9 @@ ENABLE_OPERATORS_ON(SquareDelta);
 const int FlipMask = 56;
 const int FlopMask =  7;
 
+extern uint8_t DirectionTable[64][64];
+extern uint8_t SignedDirectionTable[64][64];
+
 
 ////
 //// Inline functions
@@ -181,4 +197,22 @@ inline bool square_is_ok(Square s) {
   return file_is_ok(square_file(s)) && rank_is_ok(square_rank(s));
 }
 
+inline Direction direction_between_squares(Square s1, Square s2) {
+  return Direction(DirectionTable[s1][s2]);
+}
+
+inline int direction_is_diagonal(Square s1, Square s2) {
+  return DirectionTable[s1][s2] & 2;
+}
+
+inline bool direction_is_straight(Square s1, Square s2) {
+  return DirectionTable[s1][s2] < 2;
+}
+
+////
+//// Prototypes
+////
+
+extern void init_direction_table();
+
 #endif // !defined(SQUARE_H_INCLUDED)