X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=src%2Fbitboard.h;h=0f55810cece9864471329997ae359d56877cc8d6;hb=527d832a6de81c455cc8818e85c309fa1443f862;hp=93f838f8a6adce42ead12022368fce28959f34c9;hpb=a5e3b4eddede900c1df610e8e25026a79d706500;p=stockfish

diff --git a/src/bitboard.h b/src/bitboard.h
index 93f838f8..0f55810c 100644
--- a/src/bitboard.h
+++ b/src/bitboard.h
@@ -200,12 +200,24 @@ inline Bitboard adjacent_files_bb(Square s) {
   return shift<EAST>(file_bb(s)) | shift<WEST>(file_bb(s));
 }
 
+/// line_bb(Square, Square) returns a Bitboard representing an entire line
+/// (from board edge to board edge) that intersects the given squares.
+/// If the given squares are not on a same file/rank/diagonal, return 0.
+/// Ex. line_bb(SQ_C4, SQ_F7) returns a bitboard with the A2-G8 diagonal.
+
+inline Bitboard line_bb(Square s1, Square s2) {
+
+  assert(is_ok(s1) && is_ok(s2));
+  return LineBB[s1][s2];
+}
 
-/// between_bb() returns squares that are linearly between the given squares
+/// between_bb() returns a Bitboard representing squares that are linearly
+/// between the given squares (excluding the given squares).
 /// If the given squares are not on a same file/rank/diagonal, return 0.
+/// Ex. between_bb(SQ_C4, SQ_F7) returns a bitboard with squares D5 and E6.
 
 inline Bitboard between_bb(Square s1, Square s2) {
-  Bitboard b = LineBB[s1][s2] & ((AllSquares << s1) ^ (AllSquares << s2));
+  Bitboard b = line_bb(s1, s2) & ((AllSquares << s1) ^ (AllSquares << s2));
   return b & (b - 1); //exclude lsb
 }
 
@@ -241,7 +253,7 @@ inline Bitboard pawn_attack_span(Color c, Square s) {
 /// the given color and on the given square is a passed pawn.
 
 inline Bitboard passed_pawn_span(Color c, Square s) {
-  return forward_ranks_bb(c, s) & (adjacent_files_bb(s) | file_bb(s));
+  return pawn_attack_span(c, s) | forward_file_bb(c, s);
 }
 
 
@@ -249,7 +261,7 @@ inline Bitboard passed_pawn_span(Color c, Square s) {
 /// straight or on a diagonal line.
 
 inline bool aligned(Square s1, Square s2, Square s3) {
-  return LineBB[s1][s2] & s3;
+  return line_bb(s1, s2) & s3;
 }