fix #H285 - hiders not hiding while hero is on another level (trunk only)

From a bug report, mimics
which were exposed at the time the hero leaves a level remain unhidden
upon return no matter how long the hero is away.  It was actually expected
behavior since the old level is stuck in stasis and hiders only hide when
it's their turn to move, but it was noticeably odd.  This makes unhidden
hiders attempt to hide when hero returns to a previous level or enters a
bones level.  I reorganized the monster handling in getlev() because the
relevant part was taking place before floor objects got restored, so
hidesunder() monsters had nothing to hide under at the time.

doc/fixes35.0

@@ -220,6 +220,7 @@ when doppelgangers taking on new shape don't specifically pick nasty monster
 salamanders can use green slime corpses to cure themselves of petrification
 feedback about summoned monsters may use singular when it should use plural
 rogue's backstab bonus doesn't apply for throwing attacks
+hiding monsters who are unhidden when hero leaves a level can hide upon return
 
 
 Platform- and/or Interface-Specific Fixes

include/extern.h

@@ -1296,6 +1296,7 @@ E void NDECL(rescham);
 E void NDECL(restartcham);
 E void FDECL(restore_cham, (struct monst *));
 E boolean FDECL(hideunder, (struct monst*));
+E void FDECL(hide_monst, (struct monst *));
 E void FDECL(mon_animal_list, (BOOLEAN_P));
 E int FDECL(select_newcham_form, (struct monst *));
 E int FDECL(newcham, (struct monst *,struct permonst *,BOOLEAN_P,BOOLEAN_P));

src/mon.c

@@ -2467,6 +2467,26 @@ struct monst *mtmp;
 	return undetected;
 }
 
+/* called when returning to a previously visited level */
+void
+hide_monst(mon)
+struct monst *mon;
+{
+    if ((is_hider(mon->data) || hides_under(mon->data)) &&
+	    !(mon->mundetected || mon->m_ap_type)) {
+	xchar x = mon->mx, y = mon->my;
+	char save_viz = viz_array[y][x];
+
+	/* override vision, forcing hero to be unable to see monster's spot */
+	viz_array[y][x] &= ~(IN_SIGHT | COULD_SEE);
+	if (is_hider(mon->data)) (void)restrap(mon);
+	/* try again if mimic missed its 1/3 chance to hide */
+	if (mon->data->mlet == S_MIMIC && !mon->m_ap_type) (void)restrap(mon);
+	if (hides_under(mon->data)) (void)hideunder(mon);
+	viz_array[y][x] = save_viz;
+    }
+}
+
 short *animal_list = 0;		/* list of PM values for animal monsters */
 int animal_list_count;
 

src/restore.c

@@ -1,4 +1,4 @@
-/*	SCCS Id: @(#)restore.c	3.5	2007/02/03	*/
+/*	SCCS Id: @(#)restore.c	3.5	2007/04/21	*/
 /* Copyright (c) Stichting Mathematisch Centrum, Amsterdam, 1985. */
 /* NetHack may be freely redistributed.  See license for details. */
 
@@ -951,6 +951,7 @@ boolean ghostly;
 {
 	register struct trap *trap;
 	register struct monst *mtmp;
+	long elapsed;
 	branch *br;
 	int hpid;
 	xchar dlvl;
@@ -994,6 +995,7 @@ boolean ghostly;
 	}
 	rest_levl(fd, (boolean)((sfrestinfo.sfi1 & SFI1_RLECOMP) == SFI1_RLECOMP));
 	mread(fd, (genericptr_t)&omoves, sizeof(omoves));
+	elapsed = monstermoves - omoves;
 	mread(fd, (genericptr_t)&upstair, sizeof(stairway));
 	mread(fd, (genericptr_t)&dnstair, sizeof(stairway));
 	mread(fd, (genericptr_t)&upladder, sizeof(stairway));
@@ -1009,36 +1011,10 @@ boolean ghostly;
 	else
 	    doorindex = 0;
 
-	restore_timers(fd, RANGE_LEVEL, ghostly, monstermoves - omoves);
+	restore_timers(fd, RANGE_LEVEL, ghostly, elapsed);
 	restore_light_sources(fd);
 	fmon = restmonchn(fd, ghostly);
 
-	/* regenerate animals while on another level */
-	if (u.uz.dlevel) {
-	    register struct monst *mtmp2;
-
-	    for (mtmp = fmon; mtmp; mtmp = mtmp2) {
-		mtmp2 = mtmp->nmon;
-		if (ghostly) {
-			/* reset peaceful/malign relative to new character */
-			/* shopkeepers will reset based on name */
-			if(!mtmp->isshk) {
-			    if (is_unicorn(mtmp->data) &&
-			       sgn(u.ualign.type) == sgn(mtmp->data->maligntyp))
-				mtmp->mpeaceful = TRUE;
-			    else
-				mtmp->mpeaceful = peace_minded(mtmp->data);
-			}
-			set_malign(mtmp);
-		} else if (monstermoves > omoves)
-			mon_catchup_elapsed_time(mtmp, monstermoves - omoves);
-
-		/* update shape-changers in case protection against
-		   them is different now than when the level was saved */
-		restore_cham(mtmp);
-	    }
-	}
-
 	rest_worm(fd);	/* restore worm information */
 	ftrap = 0;
 	while (trap = newtrap(),
@@ -1060,14 +1036,32 @@ boolean ghostly;
 	for (x = 0; x < COLNO; x++)
 	    for (y = 0; y < ROWNO; y++)
 		level.monsters[x][y] = (struct monst *) 0;
-	for (mtmp = level.monlist; mtmp; mtmp = mtmp->nmon) {
-	    if (mtmp->isshk)
-		set_residency(mtmp, FALSE);
+	for (mtmp = fmon; mtmp; mtmp = mtmp->nmon) {
+	    if (mtmp->isshk) set_residency(mtmp, FALSE);
 	    place_monster(mtmp, mtmp->mx, mtmp->my);
 	    if (mtmp->wormno) place_wsegs(mtmp);
-	}
-	restdamage(fd, ghostly);
 
+	    /* regenerate monsters while on another level */
+	    if (!u.uz.dlevel) continue;
+	    if (ghostly) {
+		/* reset peaceful/malign relative to new character;
+		   shopkeepers will reset based on name */
+		if (!mtmp->isshk)
+		    mtmp->mpeaceful = (is_unicorn(mtmp->data) &&
+			    sgn(u.ualign.type) == sgn(mtmp->data->maligntyp)) ?
+				      TRUE : peace_minded(mtmp->data);
+		set_malign(mtmp);
+	    } else if (elapsed > 0L) {
+		mon_catchup_elapsed_time(mtmp, elapsed);
+	    }
+	    /* update shape-changers in case protection against
+	       them is different now than when the level was saved */
+	    restore_cham(mtmp);
+	    /* give hiders a chance to hide before their next move */
+	    if (ghostly || elapsed > (long)rnd(10)) hide_monst(mtmp);
+	}
+
+	restdamage(fd, ghostly);
 	rest_regions(fd, ghostly);
 	if (ghostly) {
 	    /* Now get rid of all the temp fruits... */