License upgrade to GPL version 3 or later

[empserver] / src / lib / subs / coastal.c

diff --git a/src/lib/subs/coastal.c b/src/lib/subs/coastal.c
index 2199734bbc933e1e35e23694025d76f26dd12242..aa67cf249c1ee662ab92cde187fb0c48c658afa1 100644 (file)
--- a/src/lib/subs/coastal.c
+++ b/src/lib/subs/coastal.c
@@ -1,11 +1,11 @@
 /*
  *  Empire - A multi-player, client/server Internet based war game.
- *  Copyright (C) 1986-2006, Dave Pare, Jeff Bailey, Thomas Ruschak,
- *                           Ken Stevens, Steve McClure
+ *  Copyright (C) 1986-2011, Dave Pare, Jeff Bailey, Thomas Ruschak,
+ *                Ken Stevens, Steve McClure, Markus Armbruster
  *
- *  This program is free software; you can redistribute it and/or modify
+ *  Empire is free software: you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License as published by
- *  the Free Software Foundation; either version 2 of the License, or
+ *  the Free Software Foundation, either version 3 of the License, or
  *  (at your option) any later version.
  *
  *  This program is distributed in the hope that it will be useful,
@@ -14,8 +14,7 @@
  *  GNU General Public License for more details.
  *
  *  You should have received a copy of the GNU General Public License
- *  along with this program; if not, write to the Free Software
- *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
  *
  *  ---
  *
@@ -26,93 +25,86 @@
  *  ---
  *
  *  coastal.c: Routines to calculate the coastal flag
- * 
+ *
  *  Known contributors to this file:
  *     Ron Koenderink, 2005
- *     
  */
 
 #include <config.h>
 
-#include "prototypes.h"
 #include "file.h"
 #include "path.h"
+#include "prototypes.h"
+#include "sect.h"
 
-static void
-update_coastal_flag(struct sctstr *sp, struct sctstr *sectp)
+static int
+update_coastal_flag(coord x, coord y, coord ign_x, coord ign_y)
 {
     int n;
     struct sctstr sect;
 
     for (n = 1; n <= 6; n++) { /* Directions */
-       getsect(sp->sct_x + diroff[n][0], sp->sct_y + diroff[n][1], &sect);
-       if (sectp && sectp->sct_x == sect.sct_x &&
-           sectp->sct_y == sect.sct_y)
+       getsect(x + diroff[n][0], y + diroff[n][1], &sect);
+       if (sect.sct_x == ign_x && sect.sct_y == ign_y)
            continue;
        if (sect.sct_type == SCT_WATER || sect.sct_type == SCT_BTOWER ||
-           sect.sct_type == SCT_BSPAN) {
-           if (!sp->sct_coastal) {
-               sp->sct_coastal = 1;
-               putsect(sp);
-           }
-           return;
-       }
-    }
-    if (sp->sct_coastal) {
-        sp->sct_coastal = 0;
-       putsect(sp);
+           sect.sct_type == SCT_BSPAN)
+           return 1;
     }
+
+    return 0;
 }
 
-static void
-coastal_sea_to_land(struct sctstr *sp, int des)
+static int
+coastal_sea_to_land(coord x, coord y)
 {
-    int n;
+    int n, c;
     struct sctstr sect;
 
-    update_coastal_flag(sp, NULL);
-
     for (n = 1; n <= 6; n++) { /* Directions */
-       getsect(sp->sct_x + diroff[n][0], sp->sct_y + diroff[n][1], &sect);
-       update_coastal_flag(&sect, sp);
+       getsect(x + diroff[n][0], y + diroff[n][1], &sect);
+       c = update_coastal_flag(sect.sct_x, sect.sct_y, x, y);
+       if (!sect.sct_coastal != !c) {
+           sect.sct_coastal = c;
+           putsect(&sect);
+       }
     }
+
+    return update_coastal_flag(x, y, x, y);
 }
 
-static void
-coastal_land_to_sea(struct sctstr *sp, int des)
+static int
+coastal_land_to_sea(coord x, coord y)
 {
     int n;
     struct sctstr sect;
 
-    sp->sct_coastal = 1;
-    putsect(sp);
-
     for (n = 1; n <= 6; ++n) { /* Directions */
-       getsect(sp->sct_x + diroff[n][0], sp->sct_y + diroff[n][1], &sect);
+       getsect(x + diroff[n][0], y + diroff[n][1], &sect);
        if (!sect.sct_coastal) {
            sect.sct_coastal = 1;
            putsect(&sect);
        }
     }
+
+    return 1;
 }
 
+/*
+ * Compute coastal flags for a change of SP from OLDDES to NEWDES.
+ * Update adjacent sectors, but don't touch SP.
+ * Return new coastal flag for SP.
+ */
 void
-set_coastal(struct sctstr *sp, int des)
+set_coastal(struct sctstr *sp, int olddes, int newdes)
 {
-    int old_water = 0;
-    int new_water = 0;
-
-    if (sp->sct_type == SCT_WATER || sp->sct_type == SCT_BTOWER ||
-       sp->sct_type == SCT_BSPAN)
-       old_water = 1;
-
-    if (des == SCT_WATER || des == SCT_BTOWER || des== SCT_BSPAN)
-       new_water = 1;
+    int old_water = olddes == SCT_WATER
+       || olddes == SCT_BTOWER || olddes == SCT_BSPAN;
+    int new_water = newdes == SCT_WATER
+       || newdes == SCT_BTOWER || newdes == SCT_BSPAN;
 
-    if (new_water == old_water)
-       return;
-    else if (new_water)
-       coastal_land_to_sea(sp, des);
-    else
-       coastal_sea_to_land(sp, des);
+    if (new_water != old_water)
+       sp->sct_coastal = new_water
+           ? coastal_land_to_sea(sp->sct_x, sp->sct_y)
+           : coastal_sea_to_land(sp->sct_x, sp->sct_y);
 }