fairland: Make actual island sizes fair

[empserver] / src / util / fairland.c

diff --git a/src/util/fairland.c b/src/util/fairland.c
index 501f52b658df0d8dac1693879f66eb3e4661e573..e8f0ee2e6252b257984df7437e66179fd4c06656 100644 (file)
--- a/src/util/fairland.c
+++ b/src/util/fairland.c
@@ -65,7 +65,7 @@
  * Each continent has a "sphere of influence": the set of sectors
  * closer to it than to any other continent.  Each island is entirely
  * in one such sphere, and each sphere contains the same number of
- * islands.
+ * islands with the same sizes.
  *
  * Pick an island size, and place one island's first sector into each
  * sphere, randomly.  Then add one sector to each island in turn,
@@ -944,15 +944,17 @@ can_grow_at(int c, int x, int y)
 static void
 adj_land_update(int x, int y)
 {
+    int is_land = own[x][y] != -1;
     int dir, nx, ny, noff;
 
-    assert(own[x][y] != -1);
-
     for (dir = DIR_FIRST; dir <= DIR_LAST; dir++) {
        nx = new_x(x + diroff[dir][0]);
        ny = new_y(y + diroff[dir][1]);
        noff = XYOFFSET(nx, ny);
-       adj_land[noff] |= 1u << DIR_BACK(dir);
+       if (is_land)
+           adj_land[noff] |= 1u << DIR_BACK(dir);
+       else
+           adj_land[noff] &= ~(1u << DIR_BACK(dir));
     }
 }
 
@@ -1117,13 +1119,17 @@ grow_islands(void)
 {
     int n = ni / nc;
     int stunted_islands = 0;
-    int i, j, c, done, secs, isiz;
+    int xzone_valid = 0;
+    int i, j, c, done, secs, isiz, x, y;
 
-    xzone_init(nc);
     init_spheres_of_influence();
 
     for (i = 0; i < n; i++) {
        c = nc + i * nc;
+
+       if (!xzone_valid)
+           xzone_init(c);
+
        isiz = roll(is) + roll0(is);
 
        for (j = 0; j < nc; j++) {
@@ -1142,6 +1148,21 @@ grow_islands(void)
            }
        }
 
+       if (!done) {
+           secs--;
+           for (j = 0; j < nc; j++) {
+               if (isecs[c + j] != secs) {
+                   isecs[c + j]--;
+                   assert(isecs[c + j] == secs);
+                   x = sectx[c + j][secs];
+                   y = secty[c + j][secs];
+                   own[x][y] = -1;
+                   adj_land_update(x, y);
+               }
+           }
+           xzone_valid = 0;
+       }
+
        for (j = 0; j < nc; j++)
            stunted_islands += isecs[c + j] != isiz;