common/borders.c

   1 /****************************************************************************
   2  Freeciv - Copyright (C) 2004 - The Freeciv Team
   3    This program is free software; you can redistribute it and/or modify
   4    it under the terms of the GNU General Public License as published by
   5    the Free Software Foundation; either version 2, or (at your option)
   6    any later version.
   7
   8    This program is distributed in the hope that it will be useful,
   9    but WITHOUT ANY WARRANTY; without even the implied warranty of
  10    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11    GNU General Public License for more details.
  12 ****************************************************************************/
  13
  14 #ifdef HAVE_CONFIG_H
  15 #include <fc_config.h>
  16 #endif
  17
  18 /* utility */
  19 #include "fcintl.h"
  20 #include "log.h"
  21
  22 /* common */
  23 #include "game.h"
  24 #include "tile.h"
  25 #include "unit.h"
  26
  27 #include "borders.h"
  28
  29 /*************************************************************************
  30   Border radius sq from given border source tile.
  31 *************************************************************************/
  32 int tile_border_source_radius_sq(struct tile *ptile)
  33 {
  34   struct city *pcity;
  35   int radius_sq = 0;
  36
  37   if (BORDERS_DISABLED == game.info.borders) {
  38     return 0;
  39   }
  40
  41   pcity = tile_city(ptile);
  42
  43   if (pcity) {
  44     radius_sq = game.info.border_city_radius_sq;
  45     /* Limit the addition due to the city size. A city size of 60 or more is
  46      * possible with a city radius of 5 (radius_sq = 26). */
  47     radius_sq += MIN(city_size_get(pcity), CITY_MAP_MAX_RADIUS_SQ)
  48                  * game.info.border_size_effect;
  49   } else {
  50     base_type_iterate(pbase) {
  51       if (tile_has_base(ptile, pbase) && territory_claiming_base(pbase)) {
  52         radius_sq = pbase->border_sq;
  53         break;
  54       }
  55     } base_type_iterate_end;
  56   }
  57
  58   return radius_sq;
  59 }
  60
  61 /*************************************************************************
  62   Border source strength
  63 *************************************************************************/
  64 int tile_border_source_strength(struct tile *ptile)
  65 {
  66   struct city *pcity;
  67   int strength = 0;
  68
  69   if (BORDERS_DISABLED == game.info.borders) {
  70     return 0;
  71   }
  72
  73   pcity = tile_city(ptile);
  74
  75   if (pcity) {
  76     strength = city_size_get(pcity) + 2;
  77   } else {
  78     base_type_iterate(pbase) {
  79       if (tile_has_base(ptile, pbase) && territory_claiming_base(pbase)) {
  80         strength = 1;
  81         break;
  82       }
  83     } base_type_iterate_end;
  84   }
  85
  86   return strength;
  87 }
  88
  89 /*************************************************************************
  90   Border source strength at tile
  91 *************************************************************************/
  92 int tile_border_strength(struct tile *ptile, struct tile *source)
  93 {
  94   int full_strength = tile_border_source_strength(source);
  95   int sq_dist = sq_map_distance(ptile, source);
  96
  97   if (sq_dist > 0) {
  98     return full_strength * full_strength / sq_dist;
  99   } else {
 100     return FC_INFINITY;
 101   }
 102 }
 103
 104 /*************************************************************************
 105   Is given tile source to borders.
 106 *************************************************************************/
 107 bool is_border_source(struct tile *ptile)
 108 {
 109   if (tile_city(ptile)) {
 110     return TRUE;
 111   }
 112
 113   if (tile_owner(ptile) != NULL) {
 114     base_type_iterate(pbase) {
 115       if (tile_has_base(ptile, pbase) && territory_claiming_base(pbase)) {
 116         return TRUE;
 117       }
 118     } base_type_iterate_end;
 119   }
 120
 121   return FALSE;
 122 }