Module Name: src
Committed By: rillig
Date: Sun May 29 14:50:37 UTC 2022
Modified Files:
src/games/gomoku: gomoku.h
Log Message:
gomoku: provide a more gentle introduction to the code
No binary change.
To generate a diff of this commit:
cvs rdiff -u -r1.51 -r1.52 src/games/gomoku/gomoku.h
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/games/gomoku/gomoku.h
diff -u src/games/gomoku/gomoku.h:1.51 src/games/gomoku/gomoku.h:1.52
--- src/games/gomoku/gomoku.h:1.51 Sun May 29 14:37:44 2022
+++ src/games/gomoku/gomoku.h Sun May 29 14:50:37 2022
@@ -1,4 +1,4 @@
-/* $NetBSD: gomoku.h,v 1.51 2022/05/29 14:37:44 rillig Exp $ */
+/* $NetBSD: gomoku.h,v 1.52 2022/05/29 14:50:37 rillig Exp $ */
/*
* Copyright (c) 1994
@@ -40,27 +40,32 @@
#include <stdio.h>
/*
- * The board consists of 19x19 spots, the coordinates are 1-based. The board
- * is surrounded by border spots.
+ * The gomoku 'board' mainly consists of the playing area of BSZ x BSZ spots.
+ * The playing area uses 1-based coordinates. Around the playing area is a
+ * rectangle of border spots, to avoid having to check the coordinates when
+ * calculating spot coordinates. The left and right border overlap, to save a
+ * few bytes.
*/
#define BSZ 19
#define BAREA ((1 + BSZ + 1) * (BSZ + 1) + 1)
/*
- * A 'frame' is a group of five or six contiguous board locations. An
+ * A 'frame' is a group of five or six contiguous spots on the board. An
* open-ended frame is one with spaces on both ends; otherwise, it is closed.
*/
#define FAREA (2 * BSZ * (BSZ - 4) + 2 * (BSZ - 4) * (BSZ - 4))
-/* values for s_occ */
+
+/* The content of a spot on the board; used in s_occ. */
#define BLACK 0
#define WHITE 1
#define EMPTY 2
#define BORDER 3
-/* A spot on the board, or in some cases one of the below special values. */
+/* A spot on the board, or one of the special values below. */
typedef unsigned short spot_index;
+#define PT(x, y) ((x) + (BSZ + 1) * (y))
/* return values for makemove, readinput */
#define MOVEOK 0
#define RESIGN 1
@@ -69,11 +74,11 @@ typedef unsigned short spot_index;
#define TIE 4
#define SAVE 5
#define END_OF_INPUT 6
-#define PT(x, y) ((x) + (BSZ + 1) * (y))
/*
- * A 'combo' is a group of intersecting frames and consists of two numbers:
- * 'F' is the number of moves to make the combo non-blockable.
+ * A 'combo' is a group of intersecting or overlapping frames and consists of
+ * two numbers:
+ * 'F' is the number of moves still needed to make the combo non-blockable.
* 'W' is the minimum number of moves needed to win once it can't be blocked.
*
* A 'force' is a combo that is one move away from being non-blockable.
