From 62b78ba0371d0a148ad1f59a61e56c7e31e90c6c Mon Sep 17 00:00:00 2001
From: Pasi Kallinen <paxed@alt.org>
Date: Wed, 10 Apr 2024 21:56:49 +0300
Subject: [PATCH] Hero movement affects water bubble direction

---
 doc/fixes3-7-0.txt |  1 +
 include/extern.h   |  1 +
 src/hack.c         |  4 +++-
 src/mkmaze.c       | 22 ++++++++++++++++++++++
 4 files changed, 27 insertions(+), 1 deletion(-)

diff --git a/doc/fixes3-7-0.txt b/doc/fixes3-7-0.txt
index 2e77d74cb..5333a8226 100644
--- a/doc/fixes3-7-0.txt
+++ b/doc/fixes3-7-0.txt
@@ -1396,6 +1396,7 @@ unblind telepathy range depends on number of telepathy granting items worn
 gold thrown or kicked at a sleeping monster with the 'greedy' attribute gets
 	caught instead of being treated as an attack but the catch message
 	neglected to report that target monster was awakened in the process
+hero movement affects the water bubble movement direction
 
 
 Fixes to 3.7.0-x General Problems Exposed Via git Repository
diff --git a/include/extern.h b/include/extern.h
index 1ff918be4..1e533c96f 100644
--- a/include/extern.h
+++ b/include/extern.h
@@ -1550,6 +1550,7 @@ extern void movebubbles(void);
 extern void water_friction(void);
 extern void save_waterlevel(NHFILE *) NONNULLARG1;
 extern void restore_waterlevel(NHFILE *) NONNULLARG1;
+extern void maybe_adjust_hero_bubble(void);
 
 /* ### mkobj.c ### */
 
diff --git a/src/hack.c b/src/hack.c
index 0930cdf3a..2286e7b87 100644
--- a/src/hack.c
+++ b/src/hack.c
@@ -2506,8 +2506,10 @@ domove(void)
         gd.domove_succeeded = 0L;
         domove_core();
         /* gd.domove_succeeded is available to make assessments now */
-        if ((gd.domove_succeeded & (DOMOVE_RUSH | DOMOVE_WALK)) != 0)
+        if ((gd.domove_succeeded & (DOMOVE_RUSH | DOMOVE_WALK)) != 0) {
             maybe_smudge_engr(ux1, uy1, u.ux, u.uy);
+            maybe_adjust_hero_bubble();
+        }
         gd.domove_attempting = 0L;
 }
 
diff --git a/src/mkmaze.c b/src/mkmaze.c
index 872a4674b..e16d7fbd6 100644
--- a/src/mkmaze.c
+++ b/src/mkmaze.c
@@ -1489,6 +1489,9 @@ fumaroles(void)
 #define gbxmax (gx.xmax - 1)
 #define gbymax (gy.ymax - 1)
 
+/* the bubble hero is in */
+static struct bubble *hero_bubble = NULL;
+
 staticfn void set_wportal(void);
 staticfn void mk_bubble(coordxy, coordxy, int);
 staticfn void mv_bubble(struct bubble *, coordxy, coordxy, boolean);
@@ -1513,6 +1516,8 @@ movebubbles(void)
 
     vision_recalc(2);
 
+    hero_bubble = NULL;
+
     if (Is_waterlevel(&u.uz)) {
         /* keep attached ball&chain separate from bubble objects */
         if (Punished)
@@ -1583,6 +1588,7 @@ movebubbles(void)
 
                             cons->next = b->cons;
                             b->cons = cons;
+                            hero_bubble = b;
                         }
                         if ((btrap = t_at(x, y)) != 0) {
                             cons = (struct container *) alloc(sizeof *cons);
@@ -1875,6 +1881,22 @@ mk_bubble(coordxy x, coordxy y, int n)
     mv_bubble(b, 0, 0, TRUE);
 }
 
+/* maybe change the movement direction of the bubble hero is in */
+void
+maybe_adjust_hero_bubble(void)
+{
+    if (!Is_waterlevel(&u.uz))
+        return;
+
+    if (!u.dx && !u.dy)
+        return;
+
+    if (hero_bubble && !rn2(2)) {
+        hero_bubble->dx = u.dx;
+        hero_bubble->dy = u.dy;
+    }
+}
+
 /*
  * The player, the portal and all other objects and monsters
  * float along with their associated bubbles.  Bubbles may overlap