Backport r10344: fix for cloud part of bug 2820876.

git-svn-id: https://crawl-ref.svn.sourceforge.net/svnroot/crawl-ref/branches/stone_soup-0.5@10345 c06c8d41-db1a-0410-9941-cceddc491573

4 files changed, 112 insertions, 18 deletions

diff --git a/crawl-ref/source/cloud.cc b/crawl-ref/source/cloud.cc
index a2a4f8609c..bbbaca890a 100644
--- a/crawl-ref/source/cloud.cc
+++ b/crawl-ref/source/cloud.cc
@@ -235,7 +235,11 @@ void check_place_cloud( cloud_type cl_type, const coord_def& p, int lifetime,
 
 int steam_cloud_damage(const cloud_struct &cloud)
 {
-    int decay = cloud.decay;
+    return steam_cloud_damage(cloud.decay);
+}
+ 
+int steam_cloud_damage(int decay)
+{
     decay = std::min(decay, 60);
     decay = std::max(decay, 10);
 
@@ -429,6 +433,90 @@ beam_type cloud2beam(cloud_type flavour)
     }
 }
 
+// NOTE: Keep in sync with in_a_cloud()
+int max_cloud_damage(cloud_type cl_type, int power)
+{
+    int speed  = player_speed();
+    int dam    = 0;
+    int resist = 0;
+
+    switch (cl_type)
+    {
+    case CLOUD_FIRE:
+        if (you.duration[DUR_FIRE_SHIELD])
+            return (0);
+        resist = player_res_fire();
+
+        // Intentional fall-throuigh
+    case CLOUD_COLD:
+        if (cl_type == CLOUD_COLD)
+            resist = player_res_cold();
+
+        if (resist <= 0)
+        {
+            dam += 32 * speed / 10;
+
+            if (resist < 0)
+                dam += 16 * speed / 10;
+        }
+        else
+        {
+            dam += 32 * speed / 10;
+            dam /= (1 + resist * resist);
+        }
+        break;
+
+    case CLOUD_STINK:
+        if (player_res_poison())
+            return (0);
+
+        dam += 2 * speed / 10;
+        break;
+
+    case CLOUD_POISON:
+        if (player_res_poison())
+            return (0);
+
+        dam += 9 * speed / 10;
+        break;
+
+    case CLOUD_STEAM:
+    {
+        ASSERT(power >= 0);
+
+        if (player_res_steam() > 0 || power == 0)
+            return (0);
+
+        const int base_dam = steam_cloud_damage(power * 10);
+        dam += (base_dam - 1) * speed / 10;
+
+        const int res_fire = player_res_fire();
+        if (res_fire < 0)
+            dam += base_dam / 2 * speed / 10;
+        else if (res_fire)
+            dam /= 1 + (res_fire / 2);
+
+        break;
+    }
+
+    case CLOUD_MIASMA:
+        if (player_prot_life() >= 3)
+            return (0);
+
+        dam += 11 * speed / 10;
+
+        break;
+    default:
+        break;
+    }
+
+    if (dam < 0)
+        dam = 0;
+
+    return (dam);
+}
+
+// NOTE: Keep in sync with max_cloud_damage()
 void in_a_cloud()
 {
     int cl = env.cgrid(you.pos());
diff --git a/crawl-ref/source/cloud.h b/crawl-ref/source/cloud.h
index 679798e48b..240ef74e77 100644
--- a/crawl-ref/source/cloud.h
+++ b/crawl-ref/source/cloud.h
@@ -55,10 +55,12 @@ void manage_clouds(void);
 
 bool is_opaque_cloud(unsigned char cloud_idx);
 int steam_cloud_damage(const cloud_struct &cloud);
+int steam_cloud_damage(int decay);
 
 cloud_type beam2cloud(beam_type flavour);
 beam_type cloud2beam(cloud_type flavour);
 
+int  max_cloud_damage(cloud_type cl_type, int power = -1);
 void in_a_cloud(void);
 
 std::string cloud_name(cloud_type type);
diff --git a/crawl-ref/source/spl-mis.cc b/crawl-ref/source/spl-mis.cc
index 543ed6cf5f..96ed2e6703 100644
--- a/crawl-ref/source/spl-mis.cc
+++ b/crawl-ref/source/spl-mis.cc
@@ -541,6 +541,18 @@ bool MiscastEffect::_explosion()
     return (true);
 }
 
+bool MiscastEffect::_big_cloud(cloud_type cl_type, int power, int size,
+                               int spread_rate)
+{
+    if (avoid_lethal( 2 * max_cloud_damage(cl_type, power) ))
+        return (false);
+
+    do_msg(true);
+    big_cloud(cl_type, kc, kt, target->pos(), power, size, spread_rate);
+
+    return (true);
+}
+
 bool MiscastEffect::_lose_stat(unsigned char which_stat,
                                unsigned char stat_loss)
 {
@@ -828,9 +840,7 @@ void MiscastEffect::_conjuration(int severity)
             mon_msg_seen   = "Smoke pours from @the_monster@'s @hands@!";
             mon_msg_unseen = "Smoke appears from out of nowhere!";
 
-            do_msg();
-            big_cloud(CLOUD_GREY_SMOKE, kc, kt, target->pos(), 20,
-                      7 + random2(7));
+            _big_cloud(CLOUD_GREY_SMOKE, 20, 7 + random2(7));
             break;
         case 1:
             you_msg      = "A wave of violent energy washes through your body!";
@@ -1998,9 +2008,7 @@ void MiscastEffect::_fire(int severity)
             mon_msg_seen   = "Smoke pours from @the_monster@'s @hands@!";
             mon_msg_unseen = "Smoke appears out of nowhere!";
 
-            do_msg();
-            big_cloud(random_smoke_type(), kc, kt, target->pos(), 20,
-                      7 + random2(7));
+            _big_cloud(random_smoke_type(), 20, 7 + random2(7));
             break;
 
         case 1:
@@ -2230,8 +2238,7 @@ void MiscastEffect::_ice(int severity)
             mon_msg_seen   = "Freezing gasses pour from @the_monster@'s "
                              "@hands@!";
 
-            do_msg();
-            big_cloud(CLOUD_COLD, kc, kt, target->pos(), 20, 8 + random2(4));
+            _big_cloud(CLOUD_COLD, 20, 8 + random2(4));
             break;
         }
         break;
@@ -2525,8 +2532,7 @@ void MiscastEffect::_air(int severity)
                              "@hands@!";
             mon_msg_unseen = "Noxious gasses appear from out of thin air!";
 
-            do_msg();
-            big_cloud(CLOUD_STINK, kc, kt, target->pos(), 20, 9 + random2(4));
+            _big_cloud(CLOUD_STINK, 20, 9 + random2(4));
             break;
         }
         break;
@@ -2557,14 +2563,12 @@ void MiscastEffect::_air(int severity)
                              "@hands@!";
             mon_msg_unseen = "Venomous gasses pour forth from the thin air!";
 
-            do_msg();
-            big_cloud(CLOUD_POISON, kc, kt, target->pos(), 20, 8 + random2(5));
+            _big_cloud(CLOUD_POISON, 20, 8 + random2(5));
             break;
         }
     }
 }
 
-// XXX MATT
 void MiscastEffect::_poison(int severity)
 {
     switch (severity)
@@ -2665,8 +2669,7 @@ void MiscastEffect::_poison(int severity)
                              "@hands@!";
             mon_msg_unseen = "Noxious gasses pour forth from the thin air!";
 
-            do_msg();
-            big_cloud(CLOUD_STINK, kc, kt, target->pos(), 20, 8 + random2(5));
+            _big_cloud(CLOUD_STINK, 20, 8 + random2(5));
             break;
 
         case 2:
@@ -2697,8 +2700,7 @@ void MiscastEffect::_poison(int severity)
                              "@hands@!";
             mon_msg_unseen = "Venomous gasses pour forth from the thin air!";
 
-            do_msg();
-            big_cloud(CLOUD_POISON, kc, kt, target->pos(), 20, 7 + random2(7));
+            _big_cloud(CLOUD_POISON, 20, 7 + random2(7));
             break;
         case 2:
             if (player_res_poison())
diff --git a/crawl-ref/source/spl-mis.h b/crawl-ref/source/spl-mis.h
index 783562587f..5def1b7dd2 100644
--- a/crawl-ref/source/spl-mis.h
+++ b/crawl-ref/source/spl-mis.h
@@ -124,6 +124,8 @@ private:
     void do_msg(bool suppress_nothing_happens = false);
     bool _ouch(int dam, beam_type flavour = BEAM_NONE);
     bool _explosion();
+    bool _big_cloud(cloud_type cl_type, int pow, int size,
+                    int spread_rate = -1);
     bool _lose_stat(unsigned char which_stat, unsigned char stat_loss);
     void _potion_effect(int pot_eff, int pow);
     bool _create_monster(monster_type what, int abj_deg, bool alert = false);