Module Name: src
Committed By: rillig
Date: Sat May 28 05:44:41 UTC 2022
Modified Files:
src/games/gomoku: makemove.c
Log Message:
gomoku: extract separate function update_overlap_same_direction
No functional change.
To generate a diff of this commit:
cvs rdiff -u -r1.27 -r1.28 src/games/gomoku/makemove.c
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/makemove.c
diff -u src/games/gomoku/makemove.c:1.27 src/games/gomoku/makemove.c:1.28
--- src/games/gomoku/makemove.c:1.27 Sat May 28 05:14:34 2022
+++ src/games/gomoku/makemove.c Sat May 28 05:44:41 2022
@@ -1,4 +1,4 @@
-/* $NetBSD: makemove.c,v 1.27 2022/05/28 05:14:34 rillig Exp $ */
+/* $NetBSD: makemove.c,v 1.28 2022/05/28 05:44:41 rillig Exp $ */
/*
* Copyright (c) 1994
@@ -34,7 +34,7 @@
#include <sys/cdefs.h>
/* @(#)makemove.c 8.2 (Berkeley) 5/3/95 */
-__RCSID("$NetBSD: makemove.c,v 1.27 2022/05/28 05:14:34 rillig Exp $");
+__RCSID("$NetBSD: makemove.c,v 1.28 2022/05/28 05:44:41 rillig Exp $");
#include "gomoku.h"
@@ -77,10 +77,9 @@ makemove(int us, int mv)
/* compute new frame values */
sp->s_wval = 0;
- struct spotstr *osp = sp;
for (int r = 4; --r >= 0; ) { /* for each direction */
int d = dd[r];
- struct spotstr *fsp = osp;
+ struct spotstr *fsp = &board[mv];
int bmask = BFLAG << r;
for (int f = 5; --f >= 0; fsp -= d) { /* for each frame */
@@ -198,7 +197,7 @@ makemove(int us, int mv)
;
}
- update_overlap(osp);
+ update_overlap(&board[mv]);
/*
* TODO: Declare a tie as soon as all frames are blocked. This is
@@ -210,8 +209,52 @@ makemove(int us, int mv)
return MOVEOK;
}
+static void
+update_overlap_same_direction(const struct spotstr *sp1,
+ const struct spotstr *sp2,
+ int a, int d, int i_minus_f, int r)
+{
+ /*
+ * count the number of empty spots to see if there is
+ * still an overlap.
+ */
+ int n = 0;
+ const struct spotstr *sp = sp1;
+ const struct spotstr *esp = NULL;
+ for (int b = i_minus_f; b < 5; b++, sp += d) {
+ if (sp->s_occ == EMPTY) {
+ esp = sp; /* save the intersection point */
+ n++;
+ }
+ }
+
+ int b = (int)(sp2->s_frame[r] - frames);
+ if (n == 0) {
+ if (sp->s_occ == EMPTY) {
+ overlap[a * FAREA + b] &= 0xA;
+ overlap[b * FAREA + a] &= 0xC;
+ intersect[a * FAREA + b] = (short)(sp - board);
+ intersect[b * FAREA + a] = (short)(sp - board);
+ } else {
+ overlap[a * FAREA + b] = 0;
+ overlap[b * FAREA + a] = 0;
+ }
+ } else if (n == 1) {
+ if (sp->s_occ == EMPTY) {
+ overlap[a * FAREA + b] &= 0xAF;
+ overlap[b * FAREA + a] &= 0xCF;
+ } else {
+ overlap[a * FAREA + b] &= 0xF;
+ overlap[b * FAREA + a] &= 0xF;
+ }
+ intersect[a * FAREA + b] = (short)(esp - board);
+ intersect[b * FAREA + a] = (short)(esp - board);
+ }
+ /* else no change, still multiple overlap */
+}
+
/*
- * fix up the overlap array due to updating spot osp.
+ * fix up the overlap array according to the changed 'osp'.
*/
static void
update_overlap(struct spotstr *osp)
@@ -221,11 +264,13 @@ update_overlap(struct spotstr *osp)
int d = dd[r];
struct spotstr *sp1 = osp;
- for (int f = 0; f < 6; f++, sp1 -= d) { /* for each frame */
+ /* for each frame that contains 'osp' */
+ for (int f = 0; f < 6; f++, sp1 -= d) {
if (sp1->s_occ == BORDER)
break;
if ((sp1->s_flags & BFLAG << r) != 0)
continue;
+
/*
* Update all other frames that intersect the current one
* to indicate whether they still overlap or not.
@@ -242,43 +287,7 @@ update_overlap(struct spotstr *osp)
if ((sp2->s_flags & BFLAG << r) != 0)
continue;
- /*
- * count the number of empty spots to see if there is
- * still an overlap.
- */
- int n = 0;
- struct spotstr *sp = sp1;
- struct spotstr *esp = NULL;
- for (int b = i - f; b < 5; b++, sp += d) {
- if (sp->s_occ == EMPTY) {
- esp = sp; /* save the intersection point */
- n++;
- }
- }
-
- int b = (int)(sp2->s_frame[r] - frames);
- if (n == 0) {
- if (sp->s_occ == EMPTY) {
- overlap[a * FAREA + b] &= 0xA;
- overlap[b * FAREA + a] &= 0xC;
- intersect[a * FAREA + b] = (short)(sp - board);
- intersect[b * FAREA + a] = (short)(sp - board);
- } else {
- overlap[a * FAREA + b] = 0;
- overlap[b * FAREA + a] = 0;
- }
- } else if (n == 1) {
- if (sp->s_occ == EMPTY) {
- overlap[a * FAREA + b] &= 0xAF;
- overlap[b * FAREA + a] &= 0xCF;
- } else {
- overlap[a * FAREA + b] &= 0xF;
- overlap[b * FAREA + a] &= 0xF;
- }
- intersect[a * FAREA + b] = (short)(esp - board);
- intersect[b * FAREA + a] = (short)(esp - board);
- }
- /* else no change, still multiple overlap */
+ update_overlap_same_direction(sp1, sp2, a, d, i - f, r);
}
/* the other directions can only intersect at spot osp */
