From a9fec4e0ae6e20b746b4236327fda1a6b87a4c38 Mon Sep 17 00:00:00 2001
From: PatR <rankin@nethack.org>
Date: Thu, 28 Jul 2022 13:42:35 -0700
Subject: [PATCH] github issue #828 - confuse monster effect when \

hero is invisible without being able to see invisible

Issue reported by EndHack:  you could see your hands glow red when
reading a scroll of confuse monster or casting the spell of confuse
monster even if you were unable to see yourself.

Switch to the blind feedback (tingling instead of glowing red) if
invisible without see invisible.

Also, have uncursed scroll or low skilled spell confer 1..2 turns
of glowing hands instead of always just 1.  (Blessed/highly skilled
stays at 2..9 turns.)

Fixes #828
---
 doc/fixes3-7-0.txt |  2 ++
 src/read.c         | 39 +++++++++++++++++++++------------------
 src/uhitm.c        | 10 +++++++---
 3 files changed, 30 insertions(+), 21 deletions(-)

diff --git a/doc/fixes3-7-0.txt b/doc/fixes3-7-0.txt
index ebbaf82ba..9f56a0e83 100644
--- a/doc/fixes3-7-0.txt
+++ b/doc/fixes3-7-0.txt
@@ -981,6 +981,8 @@ allow cutting a known spider web with wielded weapon by force-fighting the web
 holes and trapdoors have a fixed exit level
 recent changes to losedogs() could result in an infinite loop when migrating
 	monsters try to arrive as hero moves to a different level
+when invisible without see invisible you could see your hands glowing red
+	after reading a scroll of confuse monster and delivering melee hits
 
 
 Fixes to 3.7.0-x Problems that Were Exposed Via git Repository
diff --git a/src/read.c b/src/read.c
index 3299ce2bd..50cc1611f 100644
--- a/src/read.c
+++ b/src/read.c
@@ -1273,9 +1273,10 @@ static void
 seffect_confuse_monster(struct obj **sobjp)
 {
     struct obj *sobj = *sobjp;
-    boolean sblessed = sobj->blessed;
-    boolean scursed = sobj->cursed;
-    boolean confused = (Confusion != 0);
+    boolean sblessed = sobj->blessed,
+            scursed = sobj->cursed,
+            confused = (Confusion != 0),
+            altfeedback = (Blind || Invisible);
 
     if (g.youmonst.data->mlet != S_HUMAN || scursed) {
         if (!HConfusion)
@@ -1284,36 +1285,38 @@ seffect_confuse_monster(struct obj **sobjp)
     } else if (confused) {
         if (!sblessed) {
             Your("%s begin to %s%s.", makeplural(body_part(HAND)),
-                 Blind ? "tingle" : "glow ",
-                 Blind ? "" : hcolor(NH_PURPLE));
+                 altfeedback ? "tingle" : "glow ",
+                 altfeedback ? "" : hcolor(NH_PURPLE));
             make_confused(HConfusion + rnd(100), FALSE);
         } else {
             pline("A %s%s surrounds your %s.",
-                  Blind ? "" : hcolor(NH_RED),
-                  Blind ? "faint buzz" : " glow", body_part(HEAD));
+                  altfeedback ? "" : hcolor(NH_RED),
+                  altfeedback ? "faint buzz" : " glow", body_part(HEAD));
             make_confused(0L, TRUE);
         }
     } else {
+        int incr = 0;
+
         if (!sblessed) {
             Your("%s%s %s%s.", makeplural(body_part(HAND)),
-                 Blind ? "" : " begin to glow",
-                 Blind ? (const char *) "tingle" : hcolor(NH_RED),
+                 altfeedback ? "" : " begin to glow",
+                 altfeedback ? (const char *) "tingle" : hcolor(NH_RED),
                  u.umconf ? " even more" : "");
-            u.umconf++;
+            incr = rnd(2);
         } else {
-            if (Blind)
+            if (altfeedback)
                 Your("%s tingle %s sharply.", makeplural(body_part(HAND)),
                      u.umconf ? "even more" : "very");
             else
-                Your("%s glow a%s brilliant %s.",
+                Your("%s glow %s brilliant %s.",
                      makeplural(body_part(HAND)),
-                     u.umconf ? "n even more" : "", hcolor(NH_RED));
-            /* after a while, repeated uses become less effective */
-            if (u.umconf >= 40)
-                u.umconf++;
-            else
-                u.umconf += rn1(8, 2);
+                     u.umconf ? "an even more" : "a", hcolor(NH_RED));
+            incr = rn1(8, 2);
         }
+        /* after a while, repeated uses become less effective */
+        if (u.umconf >= 40)
+            incr = 1;
+        u.umconf += (unsigned) incr;
     }
 }
 
diff --git a/src/uhitm.c b/src/uhitm.c
index 9a6036bf6..927e26e19 100644
--- a/src/uhitm.c
+++ b/src/uhitm.c
@@ -5435,17 +5435,21 @@ RESTORE_WARNING_FORMAT_NONLITERAL
 static void
 nohandglow(struct monst *mon)
 {
-    char *hands = makeplural(body_part(HAND));
+    char *hands;
+    boolean altfeedback;
 
     if (!u.umconf || mon->mconf)
         return;
+
+    hands = makeplural(body_part(HAND));
+    altfeedback = (Blind || Invisible); /* Invisible == Invis && !See_invis */
     if (u.umconf == 1) {
-        if (Blind)
+        if (altfeedback)
             Your("%s stop tingling.", hands);
         else
             Your("%s stop glowing %s.", hands, hcolor(NH_RED));
     } else {
-        if (Blind)
+        if (altfeedback)
             pline_The("tingling in your %s lessens.", hands);
         else
             Your("%s no longer glow so brightly %s.", hands, hcolor(NH_RED));