[Freeciv-Dev] Re: (PR#6790) Expel enemy units

["Raimar Falke" <i-freeciv-lists@xxxxxxxxxxxxx>]

On Fri, Nov 07, 2003 at 05:34:13AM -0800, Per I. Mathisen wrote:
> On Fri, 7 Nov 2003, Raimar Falke wrote:
> > I break up an alliance and the units of the now enemy are still in my
> > cities. They should all be expelled. This could be done with either
> > of:
> >  - they just move ouf of my cities with their normal movepoints
> >  - they are placed one tile outside the city
> >  - they are teleported back to a city of their nation.
> 
> They should be teleported by bounce_unit(). I don't know why this does not
> happen properly.

To reproduce: load the game, watch Walbrzych, cancel the treaty with
Roman. The caravel shouldn't be there afterwards.

Findings: this is an update problem. If you disconnect and reconnect
the unit isn't there anymore.

I have tracked this down to
  pplayers_allied(unit_owner(punit), pplayer)
in can_player_see_unit_at(). IMHO it has to be changed to
  pplayers_allied(city_owner(pcity), pplayer)
since we want to test if the player can look inside the given city.

The attacked patch changes this.

        Raimar

-- 
 email: rf13@xxxxxxxxxxxxxxxxx
 "Many of my assistants were fans of Tolkien, who wrote 'Lord of the Rings'
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ally.gz
Description: application/gunzip

Index: common/player.c
===================================================================
RCS file: /home/freeciv/CVS/freeciv/common/player.c,v
retrieving revision 1.128
diff -u -u -r1.128 player.c
--- common/player.c     2003/10/21 21:49:55     1.128
+++ common/player.c     2003/11/07 16:18:08
@@ -263,18 +263,20 @@
   A player can see a unit if he:
   (a) can see the tile AND
   (b) can see the unit at the tile (i.e. unit not invisible at this tile) AND
-  (c) the unit is not in an unallied city
+  (c) the unit is outside a city OR in an allied city
   
   TODO: the name is confusingly similar to player_can_see_unit_at_location
   But we need to rename p_c_s_u_a_t because it is really 
   is_unit_visible_to_player_at or player_ignores_unit_invisibility_at.
 **************************************************************************/
 bool can_player_see_unit_at(struct player *pplayer, struct unit *punit,
-                            int x, int y)
+                           int x, int y)
 {
+  struct city *pcity = map_get_city(x, y);
+
   return ((map_get_known(x, y, pplayer) == TILE_KNOWN)
-         && !(map_get_city(x, y) && !pplayers_allied(unit_owner(punit), 
pplayer))
-         && player_can_see_unit_at_location(pplayer, punit, x, y));
+         && player_can_see_unit_at_location(pplayer, punit, x, y)
+         && (!pcity || pplayers_allied(city_owner(pcity), pplayer)));
 }
 
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