random level teleport fix

     From the newsgroup:  prevent monsters from level teleporting out of
the quest into the main dungeon.  The player can't do that and monsters
weren't supposed to be able to, but from time to time the quest nemesis
has seemingly vanished after reading a cursed scroll of teleportation.
His disappearance was due to ending up on a random level between the
quest entrance and the top of the dungeon.

     This also fixes an obscure bug that I noticed while trying to
reproduce that problem:  uncontrolled level teleports by the player in
the quest had 80% or thereabouts chance of ending up on the quest home
level.  All 12-15 main dungeon levels above quest entrance were included
in the random range of 1 thru current+3, then any choice which tried to
pick one of those was converted to quest level 1.  (Monster destination
wasn't getting that adjustment.)

diff --git a/doc/fixes34.2 b/doc/fixes34.2
index 487aa56af245b9e89fff3c7392eff588753db317..620e5daaaaa296fb15bc1ff5565f9e6a06f5ca61 100644 (file)
--- a/doc/fixes34.2
+++ b/doc/fixes34.2
@@ -83,6 +83,7 @@ correct invalid startup gender selection
 can no longer untrap floor containers during unskilled riding
 can no longer easily set land mines and bear traps during unskilled riding
 refine cmdassist handling for armor vs accessories
+prevent monsters from level teleporting out of the quest into the main dungeon
 
 
 Platform- and/or Interface-Specific Fixes

diff --git a/src/teleport.c b/src/teleport.c
index 503c96a1ad5f9c2599d286e041450cad2e8f86fc..a65731bb11081793501a9a6faaf90eb887742e17 100644 (file)
--- a/src/teleport.c
+++ b/src/teleport.c
@@ -1,4 +1,4 @@
-/*     SCCS Id: @(#)teleport.c 3.4     2002/11/20      */
+/*     SCCS Id: @(#)teleport.c 3.4     2003/05/31      */
 /* Copyright (c) Stichting Mathematisch Centrum, Amsterdam, 1985. */
 /* NetHack may be freely redistributed.  See license for details. */
 
@@ -1173,15 +1173,11 @@ register struct obj *obj;
 int
 random_teleport_level()
 {
-       int nlev, max_depth, min_depth;
+       int nlev, max_depth, min_depth,
+           cur_depth = (int)depth(&u.uz);
 
        if (!rn2(5) || Is_knox(&u.uz))
-               return (int)depth(&u.uz);
-
-       /* Get a random value relative to the current dungeon */
-       /* Range is 1 to current+3, current not counting */
-       nlev = rnd((int)depth(&u.uz) + 2);
-       if (nlev >= (int)depth(&u.uz)) nlev++;
+           return cur_depth;
 
        /* What I really want to do is as follows:
         * -- If in a dungeon that goes down, the new level is to be restricted
@@ -1198,11 +1194,18 @@ random_teleport_level()
         * above; endgame is handled in the caller due to its different
         * message ("disoriented").
         * --KAA
+        * 3.4.2: explicitly handle quest here too, to fix the problem of
+        * monsters sometimes level teleporting out of it into main dungeon.
         */
-       min_depth = 1;
+       min_depth = In_quest(&u.uz) ? dungeons[u.uz.dnum].depth_start : 1;
        max_depth = dunlevs_in_dungeon(&u.uz) +
                        (dungeons[u.uz.dnum].depth_start - 1);
 
+       /* Get a random value relative to the current dungeon */
+       /* Range is 1 to current+3, current not counting */
+       nlev = rn2(cur_depth + 3 - min_depth) + min_depth;
+       if (nlev >= cur_depth) nlev++;
+
        if (nlev > max_depth) {
            nlev = max_depth;
            /* teleport up if already on bottom */
@@ -1210,9 +1213,9 @@ random_teleport_level()
        }
        if (nlev < min_depth) {
            nlev = min_depth;
-           if ((int)depth(&u.uz) == min_depth) {
-               nlev += rnd(3);
-               if (nlev > max_depth)
+           if (nlev == cur_depth) {
+               nlev += rnd(3);
+               if (nlev > max_depth)
                    nlev = max_depth;
            }
        }