digging in ice

If the spot in front of a closed drawbridge was ICE, digging there
had issues....

doc/fixes3-7-0.txt

@@ -1481,6 +1481,8 @@ if eating a tin's contents caused the hero to choke to death or turn to stone,
 when hero who is poly'd into metallivore form eats a tin, bypass "smells like
 	<monster>" feedback and the "Eat it?" prompt; just eat the contents
 	along with the tin without asking
+digging in ice was handled inconsistently, particularly if done at the span
+	spot in front of closed drawbridge
 
 
 Fixes to 3.7.0-x General Problems Exposed Via git Repository

src/dig.c

@@ -859,8 +859,9 @@ liquid_flow(
     }
 
     if (ttmp)
-        (void) delfloortrap(ttmp); /* will untrap monster is one is here */
+        (void) delfloortrap(ttmp); /* will untrap monster if one is here */
     /* if any objects were frozen here, they're released now */
+    obj_ice_effects(x, y, TRUE);
     unearth_objs(x, y);
 
     if (fillmsg)
@@ -2081,7 +2082,8 @@ bury_objs(int x, int y)
     }
 }
 
-/* move objects from buriedobjlist to fobj/nexthere lists */
+/* move objects from buriedobjlist to fobj/nexthere lists; if caller
+   converts terrain from ice to something, it should call obj_ice_effects() */
 void
 unearth_objs(int x, int y)
 {

src/do.c

@@ -48,9 +48,9 @@ dodrop(void)
  */
 boolean
 boulder_hits_pool(
-    struct obj *otmp,
+    struct obj *otmp, /* the object falling into a pool or water or lava */
-    coordxy rx, coordxy ry,
+    coordxy rx, coordxy ry, /* coordinates of the pool */
-    boolean pushing)
+    boolean pushing)  /* for a boulder, whether or not it is being pushed */
 {
     if (!otmp || otmp->otyp != BOULDER) {
         impossible("Not a boulder?");
@@ -138,8 +138,9 @@ boulder_hits_pool(
                 losehp(Maybe_Half_Phys(dmg), /* lava damage */
                        "molten lava", KILLED_BY);
             } else if (!fills_up && flags.verbose
-                       && (pushing ? !Blind : cansee(rx, ry)))
+                       && (pushing ? !Blind : cansee(rx, ry))) {
                 pline("It sinks without a trace!");
+            }
         }
 
         /* boulder is now gone */
@@ -157,7 +158,10 @@ boulder_hits_pool(
  * away.
  */
 boolean
-flooreffects(struct obj *obj, coordxy x, coordxy y, const char *verb)
+flooreffects(
+    struct obj *obj,      /* the object landing on the floor */
+    coordxy x, coordxy y, /* map coordinates for spot where it is landing */
+    const char *verb)     /* "fall", "drop", "land", &c */
 {
     struct trap *t;
     struct monst *mtmp;
@@ -236,12 +240,10 @@ flooreffects(struct obj *obj, coordxy x, coordxy y, const char *verb)
                 You_hear("a CRASH! beneath you.");
             } else if (!Blind && cansee(x, y)) {
                 pline_The("boulder %s%s.",
-                          (ttyp == TRAPDOOR && !tseen)
+                          (ttyp == TRAPDOOR && !tseen) ? "triggers and " : "",
-                              ? "triggers and " : "",
+                          (ttyp == TRAPDOOR) ? "plugs a trap door"
-                          (ttyp == TRAPDOOR)
+                          : (ttyp == HOLE) ? "plugs a hole"
-                              ? "plugs a trap door"
+                            : "fills a pit");
-                              : (ttyp == HOLE) ? "plugs a hole"
-                                               : "fills a pit");
             } else {
                 Soundeffect(se_boulder_drop, 100);
                 You_hear("a boulder %s.", verb);
@@ -252,10 +254,13 @@ flooreffects(struct obj *obj, coordxy x, coordxy y, const char *verb)
          *  || mondied) -> mondead -> m_detach -> fill_pit.
          */
  deletedwithboulder:
-        if ((t = t_at(x, y)) != 0)
+        /* creating a pit in ice results in that ice being turned into
-            deltrap(t);
+           floor so we shouldn't need any special ice handing here */
-        if (u.utrap && u_at(x, y))
+        if ((t = t_at(x, y)) != 0) {
-            reset_utrap(FALSE);
+            (void) delfloortrap(t);
+            if (u.utrap && u_at(x, y))
+                reset_utrap(FALSE);
+        }
         useupf(obj, 1L);
         bury_objs(x, y);
         newsym(x, y);

src/mkmaze.c

@@ -78,19 +78,22 @@ set_levltyp(coordxy x, coordxy y, schar newtyp)
     if (isok(x, y) && newtyp >= STONE && newtyp < MAX_TYPE) {
         if (CAN_OVERWRITE_TERRAIN(levl[x][y].typ)) {
             schar oldtyp = levl[x][y].typ;
-            boolean was_ice = (levl[x][y].typ == ICE);
+            /* typ==ICE || (typ==DRAWBRIDGE_UP && drawbridgemask==DB_ICE) */
+            boolean was_ice = is_ice(x, y);
 
             levl[x][y].typ = newtyp;
             /* TODO?
              *  if oldtyp used flags or horizontal differently from
-             *  from the way newtyp will use them, clear them.
+             *  the way newtyp will use them, clear them.
              */
 
-            if (IS_LAVA(newtyp))
+            if (IS_LAVA(newtyp)) /* [what about IS_LAVA(oldtyp)=>.lit = 0?] */
                 levl[x][y].lit = 1;
-
+            if (was_ice && newtyp != ICE) {
-            if (was_ice && newtyp != ICE)
+                /* frozen corpses resume rotting, no more ice to melt away */
+                obj_ice_effects(x, y, TRUE);
                 spot_stop_timers(x, y, MELT_ICE_AWAY);
+            }
             if ((IS_FOUNTAIN(oldtyp) != IS_FOUNTAIN(newtyp))
                 || (IS_SINK(oldtyp) != IS_SINK(newtyp)))
                 count_level_features(); /* level.flags.nfountains,nsinks */

src/trap.c

@@ -455,7 +455,7 @@ struct trap *
 maketrap(coordxy x, coordxy y, int typ)
 {
     static union vlaunchinfo zero_vl;
-    boolean oldplace;
+    boolean oldplace, was_ice, clear_flags;
     struct trap *ttmp;
     struct rm *lev = &levl[x][y];
 
@@ -473,10 +473,10 @@ maketrap(coordxy x, coordxy y, int typ)
                 || (u.utraptype == TT_LAVA && !is_lava(x, y))))
             reset_utrap(FALSE);
         /* old <tx,ty> remain valid */
-    } else if (!CAN_OVERWRITE_TERRAIN(lev->typ)
+    } else if (!CAN_OVERWRITE_TERRAIN(lev->typ) /* stairs */
-               || (IS_FURNITURE(lev->typ)
-                   && (typ != PIT && typ != HOLE))
                || is_pool_or_lava(x, y)
+               || (IS_FURNITURE(lev->typ) && (typ != PIT && typ != HOLE))
+               || (lev->typ == DRAWBRIDGE_UP && typ == MAGIC_PORTAL)
                || (IS_AIR(lev->typ) && typ != MAGIC_PORTAL)
                || (typ == LEVEL_TELEP && single_level_branch(&u.uz))) {
         /* no trap on top of furniture (caller usually screens the
@@ -522,22 +522,41 @@ maketrap(coordxy x, coordxy y, int typ)
             && (is_hole(typ) || IS_DOOR(lev->typ) || IS_WALL(lev->typ)))
             add_damage(x, y, /* schedule repair */
                        ((IS_DOOR(lev->typ) || IS_WALL(lev->typ))
-                        && !svc.context.mon_moving)
+                        && !svc.context.mon_moving) ? SHOP_HOLE_COST : 0L);
-                           ? SHOP_HOLE_COST
+
-                           : 0L);
+        clear_flags = TRUE; /* assume lev->flags needs to be reset */
-        lev->doormask = 0;     /* subsumes altarmask, icedpool... */
+        /* DRAWBRIDGE_UP passes the IS_ROOM() test so check it first;
-        if (IS_ROOM(lev->typ)) /* && !IS_AIR(lev->typ) */
+           it also needs to retain lev->drawbridgemask */
+        if (lev->typ == DRAWBRIDGE_UP) {
+            /* bridge is closed and we're putting a hole or pit at the span
+               spot; this trap will be deleted if/when the bridge is opened;
+               terrain becomes room floor even if it was moat, lava, or ice */
+            clear_flags = FALSE; /* keep lev->drawbridgemask */
+            was_ice = (lev->drawbridgemask & DB_UNDER) == DB_ICE;
+            lev->drawbridgemask &= ~DB_UNDER;
+            lev->drawbridgemask |= DB_FLOOR;
+            if (was_ice) {
+                /* subset of set_levltyp() after changing ice to floor;
+                   frozen corpses resume rotting, no more ice to melt away */
+                obj_ice_effects(x, y, TRUE);
+                spot_stop_timers(x, y, MELT_ICE_AWAY);
+            }
+        } else if (IS_ROOM(lev->typ)) {
             (void) set_levltyp(x, y, ROOM);
+
         /*
          * some cases which can happen when digging
          * down while phazing thru solid areas
          */
-        else if (lev->typ == STONE || lev->typ == SCORR)
+        } else if (lev->typ == STONE || lev->typ == SCORR) {
             (void) set_levltyp(x, y, CORR);
-        else if (IS_WALL(lev->typ) || lev->typ == SDOOR)
+        } else if (IS_WALL(lev->typ) || lev->typ == SDOOR) {
             (void) set_levltyp(x, y, svl.level.flags.is_maze_lev ? ROOM
                                      : svl.level.flags.is_cavernous_lev ? CORR
                                        : DOOR);
+        }
+        if (clear_flags)
+            lev->flags = 0; /* set_levltyp doesn't take care of this [yet?] */
 
         unearth_objs(x, y);
         break;