[Freeciv-Dev] (PR#7197) optimization to base_city_map_to_map

["Jason Short" <jshort@xxxxxxxxxxxxxx>]

<URL: http://rt.freeciv.org/Ticket/Display.html?id=7197 >

The attached patch is based on one from Marcelo in PR#6721.  I've 
changed the logic slightly and also dropped the border radius from 3 to 2.

It speeds up autogames by 1-3%.  Savegames are identical.

jason

Index: common/city.c
===================================================================
RCS file: /home/freeciv/CVS/freeciv/common/city.c,v
retrieving revision 1.200
diff -u -r1.200 city.c
--- common/city.c       2003/12/06 20:37:59     1.200
+++ common/city.c       2004/01/04 23:54:34
@@ -137,7 +137,12 @@
   assert(is_valid_city_coords(city_map_x, city_map_y));
   *map_x = city_center_x + city_map_x - CITY_MAP_SIZE / 2;
   *map_y = city_center_y + city_map_y - CITY_MAP_SIZE / 2;
-  return normalize_map_pos(map_x, map_y);
+
+  /* We check the border first to avoid doing an unnecessary
+   * normalization; this is just an optimization. */
+  return (!IS_BORDER_MAP_POS(city_center_x, city_center_y,
+                            CITY_MAP_SIZE / 2)
+         || normalize_map_pos(map_x, map_y));
 }
 
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