From 47b01ac7b7d35856fae5bef60de3255e8f0d4ae5 Mon Sep 17 00:00:00 2001
From: H.G. Muller <h.g.muller@hccnet.nl>
Date: Sun, 1 Sep 2013 22:47:14 +0200
Subject: [PATCH] Implement (inaccessible) dark squares

---
 backend.c           |    4 +++-
 board.c             |    1 +
 common.h            |    2 +-
 moves.c             |    2 +-
 winboard/winboard.c |    2 ++
 5 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/backend.c b/backend.c
index 46e888e..f5ee841 100644
--- a/backend.c
+++ b/backend.c
@@ -17204,7 +17204,7 @@ PositionToFEN (int move, char *overrideCastling, int moveCounts)
                     *p++ = '+';
                     piece = (ChessSquare)(DEMOTED piece);
                 }
-                *p++ = PieceToChar(piece);
+                *p++ = (piece == DarkSquare ? '*' : PieceToChar(piece));
                 if(p[-1] == '~') {
                     /* [HGM] flag promoted pieces as '<promoted>~' (Crazyhouse) */
                     p[-1] = PieceToChar((ChessSquare)(DEMOTED piece));
@@ -17395,6 +17395,8 @@ ParseFEN (Board board, int *blackPlaysFirst, char *fen)
                 while (emptycount--)
                         board[i][(j++)+gameInfo.holdingsWidth] = EmptySquare;
 #endif
+            } else if (*p == '*') {
+		board[i][(j++)+gameInfo.holdingsWidth] = DarkSquare; p++;
             } else if (isdigit(*p)) {
 		emptycount = *p++ - '0';
                 while(isdigit(*p)) emptycount = 10*emptycount + *p++ - '0'; /* [HGM] allow > 9 */
diff --git a/board.c b/board.c
index d7c050b..48f075d 100644
--- a/board.c
+++ b/board.c
@@ -817,6 +817,7 @@ DrawSquare (int row, int column, ChessSquare piece, int do_flash)
 	snprintf(tString, 3, "%d", piece);
 	align = 4; // holdings count in upper-left corner
     }
+    if(piece == DarkSquare) square_color = 2;
     if(square_color == 2 || appData.blindfold) piece = EmptySquare;
 
     if (do_flash && piece != EmptySquare && appData.flashCount > 0) {
diff --git a/common.h b/common.h
index 9542276..65eaa9c 100644
--- a/common.h
+++ b/common.h
@@ -253,7 +253,7 @@ typedef enum {
     BlackFerz, BlackAlfil, BlackAngel, BlackMarshall, BlackWazir, BlackMan,
     BlackCannon, BlackNightrider, BlackCardinal, BlackDragon, BlackGrasshopper,
     BlackSilver, BlackFalcon, BlackLance, BlackCobra, BlackUnicorn, BlackKing,
-    EmptySquare,
+    EmptySquare, DarkSquare,
     NoRights, // [HGM] gamestate: for castling rights hidden in board[CASTLING]
     ClearBoard, WhitePlay, BlackPlay, PromotePiece, DemotePiece /*for use on EditPosition menus*/
   } ChessSquare;
diff --git a/moves.c b/moves.c
index 8cd3434..e6e8e1a 100644
--- a/moves.c
+++ b/moves.c
@@ -98,7 +98,7 @@ SameColor (ChessSquare piece1, ChessSquare piece2)
             (int) piece2 <  (int) EmptySquare);
 }
 #else
-#define SameColor(piece1, piece2) (piece1 < EmptySquare && piece2 < EmptySquare && (piece1 < BlackPawn) == (piece2 < BlackPawn))
+#define SameColor(piece1, piece2) (piece1 < EmptySquare && piece2 < EmptySquare && (piece1 < BlackPawn) == (piece2 < BlackPawn) || piece1 == DarkSquare || piece2 == DarkSquare)
 #endif
 
 char pieceToChar[] = {
diff --git a/winboard/winboard.c b/winboard/winboard.c
index 2b13222..e5df6db 100644
--- a/winboard/winboard.c
+++ b/winboard/winboard.c
@@ -3250,6 +3250,7 @@ BOOL HasHighlightInfo()
     }
 
     return result;
+
 }
 
 BOOL IsDrawArrowEnabled()
@@ -3441,6 +3442,7 @@ DrawBoardOnDC(HDC hdc, Board board, HDC tmphdc)
             DisplayHoldingsCount(hdc, x, y, flipView, (int) board[row][column]);
       else if( column == BOARD_RGHT) /* right align */
             DisplayHoldingsCount(hdc, x, y, !flipView, (int) board[row][column]);
+      else if( piece == DarkSquare) DisplayHoldingsCount(hdc, x, y, 0, 0);
       else
       if (appData.monoMode) {
         if (piece == EmptySquare) {
-- 
1.7.0.4