[Freeciv-Dev] PATCH: Smarter carriers

[zamar-fc@xxxxxxxxxxxxxxxxxxx (Joona Kiiski)]

Let's take a simple example:

You have 16 bombers on carrier:
8 of them have move points 12/16 and
8 of them have move points 2/16

Nowadays those bombers are refuelled in random order
(or more exactly, those which are first in pplayer->units)

So, if you are really lucky you don't lose any, because
carrier refuelled units which had mp 2/16.

But if you are really unlucky you lose 8 of them,
because carrier didn't understand to refuel rigth units.
(it refuelled those with higher mps)

This patch makes carriers to refuel first units which are
not going to survive without refuelling.
If carrier can't refuel all units, it refuels most valuable
units first, and so on.

--
Zamar

diff -Nur -Xdiff_ignore cvs/common/unit.c p1/common/unit.c
--- cvs/common/unit.c   Mon Mar 12 12:37:00 2001
+++ p1/common/unit.c    Mon Mar 12 20:53:54 2001
@@ -1030,7 +1030,8 @@
        misonly += get_transporter_capacity(punit);
        continue;
       }
-      if (is_air_unit(punit)) {
+      /* Don't count units which have enough fuel (>1) */
+      if (is_air_unit(punit) && punit->fuel <= 1) {
        if (unit_flag(punit->type, F_MISSILE))
          misonly--;
        else
@@ -1070,7 +1071,8 @@
        misonly += get_transporter_capacity(punit);
        continue;
       }
-      if (is_air_unit(punit)) {
+      /* Don't count units which have enough fuel (>1) */
+      if (is_air_unit(punit) && punit->fuel <= 1) {
        if (unit_flag(punit->type, F_MISSILE))
          misonly--;
        else
diff -Nur -Xdiff_ignore cvs/server/unittools.c p1/server/unittools.c
--- cvs/server/unittools.c      Mon Mar 12 12:48:45 2001
+++ p1/server/unittools.c       Mon Mar 12 23:04:35 2001
@@ -62,6 +62,11 @@
 
 static void sentry_transported_idle_units(struct unit *ptrans);
 
+static void refuel_air_units_from_carriers(struct player *pplayer);
+static struct unit *find_best_air_unit_to_refuel(struct player *pplayer, 
+                                                int x, int y, int missile);
+static struct unit *choose_more_important_refuel_target(struct unit *punit1,
+                                                       struct unit *punit2);
 
 /**************************************************************************
   used to find the best defensive unit on a square
@@ -812,11 +817,129 @@
   } unit_list_iterate_end;
        
   unit_list_unlink_all(&candidates);
-}      
-                 
+}
+
+/***************************************************************************
+Select which unit is more important to refuel:
+It's more important to refuel plane which has less fuel.
+If those are equal then we refuel more valuable unit.
+If those are equal then we refuel veteran unit.
+If those are equal then we refuel unit which has more hp.
+If those are equal then we refuel the first unit.
+****************************************************************************/
+static struct unit *choose_more_important_refuel_target(struct unit *punit1,
+                                                       struct unit *punit2)
+{
+  if (punit1->fuel != punit2->fuel)
+    return punit1->fuel < punit2->fuel? punit1: punit2;
+  
+  if (get_unit_type(punit1->type)->build_cost !=
+      get_unit_type(punit2->type)->build_cost)
+    return get_unit_type(punit1->type)->build_cost > 
+      get_unit_type(punit2->type)->build_cost? punit1: punit2;
+  
+  if (punit1->veteran != punit2->veteran)
+    return punit1->veteran > punit2->veteran? punit1: punit2;
+  
+  if (punit1->hp != punit2->hp)
+    return punit1->hp > punit2->hp? punit1: punit2;
+  return punit1;
+}
+
+/***************************************************************************
+...
+****************************************************************************/
+
+static struct unit *find_best_air_unit_to_refuel(struct player *pplayer, 
+                                                int x, int y, int missile)
+{      
+  struct unit *best_unit=NULL;
+  unit_list_iterate(map_get_tile(x, y)->units, punit) {
+    if ((unit_owner(punit) == pplayer) && is_air_unit(punit) && 
+        (!missile || unit_flag(punit->type, F_MISSILE))) {
+      /* We must check that it isn't already refuelled. */ 
+      if (punit->fuel < get_unit_type(punit->type)->fuel) { 
+        if (!best_unit) 
+          best_unit=punit;
+        else 
+          best_unit=choose_more_important_refuel_target(best_unit, punit);
+      }
+    }
+  } unit_list_iterate_end;
+  return best_unit;
+}
+
+/***************************************************************************
+...
+****************************************************************************/
+
+static void refuel_air_units_from_carriers(struct player *pplayer)
+{
+  struct unit_list carriers;
+  struct unit_list missile_carriers;
+  
+  struct unit *punit_to_refuel;
+  
+  unit_list_init(&carriers);
+  unit_list_init(&missile_carriers);
+  
+  /* Temporarily use 'fuel' on Carriers and Subs to keep track
+     of numbers of supported Air Units:   --dwp */
+
+  unit_list_iterate(pplayer->units, punit) {
+    if (unit_flag(punit->type, F_CARRIER)) {
+      unit_list_insert(&carriers, punit);
+      punit->fuel = get_unit_type(punit->type)->transport_capacity;
+    } else if (unit_flag(punit->type, F_MISSILE_CARRIER)) {
+      unit_list_insert(&missile_carriers, punit);
+      punit->fuel = get_unit_type(punit->type)->transport_capacity;
+    }
+  } unit_list_iterate_end;
+  
+  /* Now iterate through missile_carriers and
+   * refuel as many missiles as possible */
+  
+  unit_list_iterate(missile_carriers, punit) {
+    while(punit->fuel) {
+      punit_to_refuel= find_best_air_unit_to_refuel(
+          pplayer, punit->x, punit->y, 1 /*missile */);
+      if (!punit_to_refuel)
+        break; /* Didn't find any */
+      punit_to_refuel->fuel = get_unit_type(punit_to_refuel->type)->fuel;
+      punit->fuel--;
+    }
+  } unit_list_iterate_end;
+  
+  /* Now refuel air units from carriers (also not yet refuelled missiles) */
+  
+  unit_list_iterate(carriers, punit) {
+    while(punit->fuel) {
+      punit_to_refuel= find_best_air_unit_to_refuel(
+          pplayer, punit->x, punit->y, 0 /* any */);
+      if (!punit_to_refuel) 
+        break;
+      punit_to_refuel->fuel = get_unit_type(punit_to_refuel->type)->fuel;
+      punit->fuel--;
+    }
+  } unit_list_iterate_end;                     
+       
+  /* Clean up temporary use of 'fuel' on Carriers and Subs: */
+  unit_list_iterate(carriers, punit) {
+    punit->fuel = 0;
+  } unit_list_iterate_end;
+  
+  unit_list_unlink_all(&carriers);
+  
+  unit_list_iterate(missile_carriers, punit) {
+    punit->fuel = 0;
+  } unit_list_iterate_end;
+  
+  unit_list_unlink_all(&missile_carriers);
+}
+
 /***************************************************************************
-Restore unit hitpoints. (movepoint - restoration moved to 
update_unit_activities)
 Do Leonardo's Workshop upgrade if applicable.
+Restore unit hitpoints.(movepoint - restoration moved to 
update_unit_activities)
 Adjust air units for fuel: air units lose fuel unless in a city,
 on a Carrier or on a airbase special (or, for Missles, on a Submarine).
 Air units which run out of fuel get wiped.
@@ -829,125 +952,97 @@
 ****************************************************************************/
 void player_restore_units(struct player *pplayer)
 {
-  int lighthouse_effect=-1;    /* 1=yes, 0=no, -1=not yet calculated */
-  int done;
-
-  /* get Leonardo out of the way first: */
-       
+  int lighthouse_effect = player_owns_active_wonder(pplayer, B_LIGHTHOUSE);
+  
+  /* 1) get Leonardo out of the way first: */
   if (player_owns_active_wonder(pplayer, B_LEONARDO))
     handle_leonardo(pplayer);
-
-  /* Temporarily use 'fuel' on Carriers and Subs to keep track
-     of numbers of supported Air Units:   --dwp */
-  unit_list_iterate(pplayer->units, punit) {
-    if (unit_flag(punit->type, F_CARRIER) || 
-       unit_flag(punit->type, F_MISSILE_CARRIER)) {
-      punit->fuel = get_unit_type(punit->type)->transport_capacity;
-    }
-  }
-  unit_list_iterate_end;
-
+  
   unit_list_iterate(pplayer->units, punit) {
+    
+    /* 2) Modify unit hitpoints. Helicopters can even lose them. */
     unit_restore_hitpoints(pplayer, punit);
-
+    
+    /* 3) Check that unit has hitpoints */
     if(punit->hp<=0) {
       /* This should usually only happen for heli units,
         but if any other units get 0 hp somehow, catch
         them too.  --dwp  */
       notify_player_ex(pplayer, punit->x, punit->y, E_UNIT_LOST, 
-                      _("Game: Your %s has run out of hit points."),
-                      unit_name(punit->type));
+          _("Game: Your %s has run out of hit points."), 
+          unit_name(punit->type));
       gamelog(GAMELOG_UNITF, "%s lose a %s (out of hp)", 
              get_nation_name_plural(pplayer->nation),
              unit_name(punit->type));
       wipe_unit_safe(punit, &myiter);
-    } else if (is_air_unit(punit)) {
+      continue; /* Continue iterating... */
+    }
+    
+    /* 4) Check that triremes are near coastline, otherwise... */
+    if (unit_flag(punit->type, F_TRIREME) && !lighthouse_effect &&
+        !is_coastline(punit->x, punit->y) && 
+        (map_get_terrain(punit->x, punit->y) == T_OCEAN)) {
+      if (myrand(100) >= 50) {
+        notify_player_ex(pplayer, punit->x, punit->y, E_UNIT_LOST, 
+            _("Game: Your %s has been lost on the high seas."),
+            unit_name(punit->type));
+        gamelog(GAMELOG_UNITTRI, "%s Trireme lost at sea",
+            get_nation_name_plural(pplayer->nation)); 
+        wipe_unit_safe(punit, &myiter);
+      }
+    }
+    
+    /* 5) Resque planes if needed */
+    else if (is_air_unit(punit)) {
       /* Shall we emergency return home on the last vapors? */
+      
+      /* I think this is strongly against the spirit of client goto.
+       * The problem is (again) that here we know too much. -- Zamar */
+      
       if (punit->fuel == 1
          && !is_airunit_refuel_point(punit->x, punit->y,
                                      punit->owner, punit->type, 1)) {
        iterate_outward(punit->x, punit->y, punit->moves_left/3, x_itr, y_itr) {
          if (is_airunit_refuel_point(x_itr, y_itr, punit->owner, punit->type, 
0)
              && (air_can_move_between(punit->moves_left/3, punit->x, punit->y,
-                   x_itr, y_itr, punit->owner) >= 0) ) {
-             punit->goto_dest_x = x_itr;
-             punit->goto_dest_y = y_itr;
-             set_unit_activity(punit, ACTIVITY_GOTO);
-             do_unit_goto(punit, GOTO_MOVE_ANY, 0);
-             notify_player_ex(pplayer, punit->x, punit->y, E_NOEVENT, 
-                              _("Game: Your %s has returned to refuel."),
-                              unit_name(punit->type));
-             goto OUT;
-           }
+            x_itr, y_itr, punit->owner) >= 0) ) {
+           punit->goto_dest_x = x_itr;
+           punit->goto_dest_y = y_itr;
+           set_unit_activity(punit, ACTIVITY_GOTO);
+           do_unit_goto(punit, GOTO_MOVE_ANY, 0);
+           notify_player_ex(pplayer, punit->x, punit->y, E_NOEVENT, 
+                            _("Game: Your %s has returned to refuel."),
+                            unit_name(punit->type));
+           goto OUT;
+         }
        } iterate_outward_end;
       }
     OUT:
-
+      
+      /* 6) Update fuel */
       punit->fuel--;
+      
+      /* 7) Automatically refuel air units in cities and airbases */
       if(map_get_city(punit->x, punit->y) ||
          map_get_special(punit->x, punit->y)&S_AIRBASE)
        punit->fuel=get_unit_type(punit->type)->fuel;
-      else {
-       done = 0;
-       if (unit_flag(punit->type, F_MISSILE)) {
-         /* Want to preferentially refuel Missiles from Subs,
-            to leave space on co-located Carriers for normal air units */
-         unit_list_iterate(map_get_tile(punit->x, punit->y)->units, punit2) 
-           if (!done && unit_flag(punit2->type, F_MISSILE_CARRIER)
-               && punit2->fuel
-               && punit2->owner == punit->owner) {
-             punit->fuel = get_unit_type(punit->type)->fuel;
-             punit2->fuel--;
-             done = 1;
-           }
-         unit_list_iterate_end;
-       }
-       if (!done) {
-         /* Non-Missile or not refueled by Subs: use Carriers: */
-         unit_list_iterate(map_get_tile(punit->x, punit->y)->units, punit2) 
-           if (!done && unit_flag(punit2->type,F_CARRIER) && punit2->fuel) {
-             punit->fuel = get_unit_type(punit->type)->fuel;
-             punit2->fuel--;
-             done = 1;
-           }
-         unit_list_iterate_end;
-       }
-      }
-      if(punit->fuel<=0) {
-       notify_player_ex(pplayer, punit->x, punit->y, E_UNIT_LOST, 
-                        _("Game: Your %s has run out of fuel."),
-                        unit_name(punit->type));
-       gamelog(GAMELOG_UNITF, "%s lose a %s (fuel)", 
-               get_nation_name_plural(pplayer->nation),
-               unit_name(punit->type));
-       wipe_unit_safe(punit, &myiter);
-      }
-    } else if (unit_flag(punit->type, F_TRIREME) && (lighthouse_effect!=1) &&
-              !is_coastline(punit->x, punit->y) &&
-              (map_get_terrain(punit->x, punit->y) == T_OCEAN)) {
-      if (lighthouse_effect == -1) {
-       lighthouse_effect = player_owns_active_wonder(pplayer, B_LIGHTHOUSE);
-      }
-      if ((!lighthouse_effect) && (myrand(100) >= 50)) {
-       notify_player_ex(pplayer, punit->x, punit->y, E_UNIT_LOST, 
-                        _("Game: Your %s has been lost on the high seas."),
-                        unit_name(punit->type));
-       gamelog(GAMELOG_UNITTRI, "%s Trireme lost at sea",
-               get_nation_name_plural(pplayer->nation));
-       wipe_unit_safe(punit, &myiter);
-      }
     }
-  }
-  unit_list_iterate_end;
+  } unit_list_iterate_end;
+
+  /* 8) Use carriers and submarines to refuel air units */
+  refuel_air_units_from_carriers(pplayer);
   
-  /* Clean up temporary use of 'fuel' on Carriers and Subs: */
+  /* 9) Check if there are air units without fuel */
   unit_list_iterate(pplayer->units, punit) {
-    if (unit_flag(punit->type, F_CARRIER) || 
-       unit_flag(punit->type, F_MISSILE_CARRIER)) {
-      punit->fuel = 0;
-    }
-  }
-  unit_list_iterate_end;
+    if(is_air_unit(punit) && punit->fuel<=0) {
+      notify_player_ex(pplayer, punit->x, punit->y, E_UNIT_LOST, 
+                      _("Game: Your %s has run out of fuel."),
+                      unit_name(punit->type));
+      gamelog(GAMELOG_UNITF, "%s lose a %s (fuel)", 
+             get_nation_name_plural(pplayer->nation), unit_name(punit->type));
+      wipe_unit_safe(punit, &myiter);
+    } 
+  } unit_list_iterate_end;
 }
 
 /****************************************************************************