client/climap.c

   1 /**********************************************************************
   2  Freeciv - Copyright (C) 2002 - The Freeciv Project
   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 /* common */
  19 #include "map.h"
  20 #include "shared.h"
  21
  22 /* client */
  23 #include "client_main.h"
  24 #include "climap.h"
  25 #include "tilespec.h"           /* tileset_is_isometric(tileset) */
  26
  27 /************************************************************************
  28  A tile's "known" field is used by the server to store whether _each_
  29  player knows the tile.  Client-side, it's used as an enum known_type
  30  to track whether the tile is known/fogged/unknown.
  31
  32  Judicious use of this function also makes things very convenient for
  33  civworld, since it uses both client and server-style storage; since it
  34  uses the stock tilespec.c file, this function serves as a wrapper.
  35
  36 *************************************************************************/
  37 enum known_type client_tile_get_known(const struct tile *ptile)
  38 {
  39   if (NULL == client.conn.playing) {
  40     if (client_is_observer()) {
  41       return TILE_KNOWN_SEEN;
  42     } else {
  43       return TILE_UNKNOWN;
  44     }
  45   }
  46   return tile_get_known(ptile, client.conn.playing);
  47 }
  48
  49 /**************************************************************************
  50   Convert the given GUI direction into a map direction.
  51
  52   GUI directions correspond to the current viewing interface, so that
  53   DIR8_NORTH is up on the mapview.  map directions correspond to the
  54   underlying map tiles, so that DIR8_NORTH means moving with a vector of
  55   (0,-1).  Neither necessarily corresponds to "north" on the underlying
  56   world (once iso-maps are possible).
  57
  58   See also map_to_gui_dir().
  59 **************************************************************************/
  60 enum direction8 gui_to_map_dir(enum direction8 gui_dir)
  61 {
  62   if (tileset_is_isometric(tileset)) {
  63     return dir_ccw(gui_dir);
  64   } else {
  65     return gui_dir;
  66   }
  67 }
  68
  69 /**************************************************************************
  70   Convert the given GUI direction into a map direction.
  71
  72   See also gui_to_map_dir().
  73 **************************************************************************/
  74 enum direction8 map_to_gui_dir(enum direction8 map_dir)
  75 {
  76   if (tileset_is_isometric(tileset)) {
  77     return dir_cw(map_dir);
  78   } else {
  79     return map_dir;
  80   }
  81 }
  82
  83 /***************************************************************************
  84   Client variant of city_tile().  This include the case of this could a
  85   ghost city (see client/packhand.c).  In a such case, the returned tile
  86   is an approximative position of the city on the map.
  87 ***************************************************************************/
  88 struct tile *client_city_tile(const struct city *pcity)
  89 {
  90   int dx, dy;
  91   double x = 0, y = 0;
  92   size_t num = 0;
  93
  94   if (NULL == pcity) {
  95     return NULL;
  96   }
  97
  98   if (NULL != city_tile(pcity)) {
  99     /* Normal city case. */
 100     return city_tile(pcity);
 101   }
 102
 103   whole_map_iterate(ptile) {
 104     int tile_x, tile_y;
 105
 106     index_to_map_pos(&tile_x, &tile_y, tile_index(ptile));
 107     if (pcity == tile_worked(ptile)) {
 108       if (0 == num) {
 109         x = tile_x;
 110         y = tile_y;
 111         num = 1;
 112       } else {
 113         num++;
 114         base_map_distance_vector(&dx, &dy, (int)x, (int)y, tile_x, tile_y);
 115         x += (double) dx / num;
 116         y += (double) dy / num;
 117       }
 118     }
 119   } whole_map_iterate_end;
 120
 121   if (0 < num) {
 122     return map_pos_to_tile((int) x, (int) y);
 123   } else {
 124     return NULL;
 125   }
 126 }
 127
 128 /**************************************************************************
 129   Returns TRUE when a tile is available to be worked, or the city itself
 130   is currently working the tile (and can continue).
 131
 132   See also city_can_work_tile() (common/city.[ch]).
 133 **************************************************************************/
 134 bool client_city_can_work_tile(const struct city *pcity,
 135                                const struct tile *ptile)
 136 {
 137   return base_city_can_work_tile(client_player(), pcity, ptile);
 138 }