Apply r10031 to trunk.

git-svn-id: https://crawl-ref.svn.sourceforge.net/svnroot/crawl-ref/trunk@10034 c06c8d41-db1a-0410-9941-cceddc491573

2 files changed, 67 insertions, 3 deletions

diff --git a/crawl-ref/docs/tiles_help.txt b/crawl-ref/docs/tiles_help.txt
index 231dd7ebb3..3886ed0cb1 100644
--- a/crawl-ref/docs/tiles_help.txt
+++ b/crawl-ref/docs/tiles_help.txt
@@ -9,6 +9,36 @@ It has been tested successfully with cards as old as the i865.  Unfortunately,
 it has been known to be slow on the i810 and there is little to be done in that
 case but to run the console version instead or switch to a different machine.
 
+You can try tweaking a number of options to see whether performance improves:
+
+tile_title_screen = false
+    For weak drivers, the title screen can take a long time to load. If this
+    bothers you, you can easily deactivate it.
+
+travel_delay = -1
+    This setting suppresses redrawing until travelling is finished or
+    interrupted.
+
+tile_update_rate = 1000
+    By default, the screen gets redrawn at least every 1000 milliseconds,
+    more often if you take actions that change the display. You could try
+    cranking up this value, though this may lead to updating taking too long.
+
+tile_tooltip_ms = 0
+    Deactivating the tooltips means there's less stuff to draw every time.
+
+clear_map = false
+    Not having to redraw remembered monsters outside your line of sight
+    takes some load off the redrawing routines.
+
+tile_window_width   = 1024
+tile_window_height  = 768
+    The larger the map area the more cells there are to redraw each turn.
+    If you've got a large display showing way more than the necessary 17x17
+    grids of the map, you could try specifying a lower resolution.
+
+
+
                   Tiles mouseclick item interaction
 
 If you're playing with Tiles compiled, you'll find several shortcuts to
diff --git a/crawl-ref/source/monstuff.cc b/crawl-ref/source/monstuff.cc
index a9094fcba1..622309d23c 100644
--- a/crawl-ref/source/monstuff.cc
+++ b/crawl-ref/source/monstuff.cc
@@ -2095,7 +2095,12 @@ bool monster_polymorph(monsters *monster, monster_type targetc,
                                               ENCH_SHAPESHIFTER);
     mon_enchant summon    = monster->get_ench(ENCH_SUMMON);
     mon_enchant tp        = monster->get_ench(ENCH_TP);
+
     monster_spells spl    = monster->spells;
+    const bool need_save_spells
+            = (!name.empty()
+               && (!mons_class_flag(monster->type, M_SPELLCASTER)
+                   || mons_class_flag(monster->type, M_ACTUAL_SPELLS)));
 
     // deal with mons_sec
     monster->type         = targetc;
@@ -2109,9 +2114,17 @@ bool monster_polymorph(monsters *monster, monster_type targetc,
     monster->flags = flags;
     monster->god   = god;
 
-    // Keep spells for named monsters.
-    if (!name.empty())
+    // Keep spells for named monsters, but don't override innate ones
+    // for dragons and the like. This means that Sigmund polymorphed
+    // into a goblin will still cast spells, but if he ends up as a
+    // swamp drake he'll breathe fumes and, if polymorphed further,
+    // won't remember his spells anymore.
+    if (need_save_spells
+        && (!mons_class_flag(monster->type, M_SPELLCASTER)
+            || mons_class_flag(monster->type, M_ACTUAL_SPELLS)))
+    {
         monster->spells = spl;
+    }
 
     monster->add_ench(abj);
     monster->add_ench(charm);
@@ -6345,6 +6358,15 @@ static bool _is_emergency_spell(const monster_spells &msp, int spell)
     return (msp[5] == spell);
 }
 
+static bool _mon_has_spells(monsters *monster)
+{
+    for (int i = 0; i < NUM_MONSTER_SPELL_SLOTS; ++i)
+        if (monster->spells[i] != SPELL_NO_SPELL)
+            return (true);
+
+    return (false);
+}
+
 //---------------------------------------------------------------
 //
 // handle_spell
@@ -6359,6 +6381,15 @@ static bool _handle_spell(monsters *monster, bolt &beem)
     bool finalAnswer   = false;   // as in: "Is that your...?" {dlb}
     const spell_type draco_breath = _get_draconian_breath_spell(monster);
 
+    // A polymorphed unique will retain his or her spells even in another
+    // form. If the new form has the SPELLCASTER flag, casting happens as
+    // normally, otherwise we need to enforce it, but it only happens with
+    // a 50% chance.
+    const bool spellcasting_poly
+            = !mons_class_flag(monster->type, M_SPELLCASTER)
+              && mons_class_flag(monster->type, M_SPEAKS)
+              && _mon_has_spells(monster);
+
     if (is_sanctuary(monster->pos()) && !mons_wont_attack(monster))
         return (false);
 
@@ -6366,6 +6397,7 @@ static bool _handle_spell(monsters *monster, bolt &beem)
     if (mons_is_sleeping(monster)
         || mons_is_submerged(monster)
         || !mons_class_flag(monster->type, M_SPELLCASTER)
+           && !spellcasting_poly
            && draco_breath == SPELL_NO_SPELL)
     {
         return (false);
@@ -6381,7 +6413,7 @@ static bool _handle_spell(monsters *monster, bolt &beem)
     god_type god = (priest || !(priest || wizard)) ? monster->god : GOD_NO_GOD;
 
     if (silenced(monster->pos())
-        && (priest || wizard
+        && (priest || wizard || spellcasting_poly
             || mons_class_flag(monster->type, M_SPELL_NO_SILENT)))
     {
         return (false);
@@ -6405,6 +6437,8 @@ static bool _handle_spell(monsters *monster, bolt &beem)
     {
         return (false);
     }
+    else if (spellcasting_poly && coinflip()) // 50% chance of not casting
+        return (false);
     else
     {
         spell_type spell_cast = SPELL_NO_SPELL;