Experimental support for monster shields, needs more work for rationalising shield class for monsters with player and beam to-hit.

git-svn-id: https://crawl-ref.svn.sourceforge.net/svnroot/crawl-ref/trunk@2727 c06c8d41-db1a-0410-9941-cceddc491573

6 files changed, 166 insertions, 47 deletions

diff --git a/crawl-ref/source/beam.cc b/crawl-ref/source/beam.cc
index 4e532cb96d..ba3c94cacc 100644
--- a/crawl-ref/source/beam.cc
+++ b/crawl-ref/source/beam.cc
@@ -3129,14 +3129,14 @@ static int affect_player( bolt &beam )
 #endif
                     if (hit < block)
                     {
-                        you.shield_blocks++;
                         mprf( "You block the %s.", beam.name.c_str() );
-                        exercise( SK_SHIELDS, exer + 1 );
+                        you.shield_block_succeeded();
                         return (BEAM_STOP);
                     }
 
                     // some training just for the "attempt"
-                    exercise( SK_SHIELDS, exer );
+                    if (coinflip())
+                        exercise( SK_SHIELDS, exer );
                 }
 
                 if (player_light_armour(true) && !beam.aimed_at_feet
@@ -3878,6 +3878,26 @@ static int affect_monster(bolt &beam, monsters *mon)
         return (0);
     }
 
+    // The monster may block the beam.
+    if (!engulfs && beam_is_blockable(beam))
+    {
+        const int shield_block = mon->shield_bonus();
+        if (shield_block > 0)
+        {
+            const int hit = random2( beam.hit * 130 / 100
+                                     + mon->shield_block_penalty() );
+            if (hit < shield_block && mons_near(mon)
+                && player_monster_visible(mon))
+            {
+                mprf("%s blocks the %s.",
+                     mon->name(DESC_CAP_THE).c_str(),
+                     beam.name.c_str());
+                mon->shield_block_succeeded();
+                return (BEAM_STOP);
+            }
+        }
+    }
+
     update_hurt_or_helped(beam, mon);
 
     // the beam hit.
diff --git a/crawl-ref/source/debug.cc b/crawl-ref/source/debug.cc
index d2cbb2510e..d3d020b1ab 100644
--- a/crawl-ref/source/debug.cc
+++ b/crawl-ref/source/debug.cc
@@ -1448,8 +1448,8 @@ void stethoscope(int mwh)
           (menv[i].foe == MHITNOT)            ? "none" :
           (menv[menv[i].foe].type == -1)      ? "unassigned monster" 
           : menv[menv[i].foe].name(DESC_PLAIN, true).c_str()),
-         menv[i].foe, 
-         menv[i].foe_memory,          
+         menv[i].foe,
+         menv[i].foe_memory,
          menv[i].target_x, menv[i].target_y );
 
     // print resistances
diff --git a/crawl-ref/source/enum.h b/crawl-ref/source/enum.h
index eb4859627b..a7cecf10c4 100644
--- a/crawl-ref/source/enum.h
+++ b/crawl-ref/source/enum.h
@@ -1825,6 +1825,7 @@ enum mon_inv_type           // (int) menv[].inv[]
                             // for monsters that can use two weapons.
     MSLOT_MISSILE,
     MSLOT_ARMOUR,
+    MSLOT_SHIELD,
     MSLOT_MISCELLANY,
     MSLOT_POTION,
     MSLOT_WAND,
diff --git a/crawl-ref/source/fight.cc b/crawl-ref/source/fight.cc
index 4a5a9c7f5d..e132835e88 100644
--- a/crawl-ref/source/fight.cc
+++ b/crawl-ref/source/fight.cc
@@ -545,9 +545,16 @@ bool melee_attack::player_attack()
         if (Options.tutorial_left)
             Options.tut_melee_counter++;        
 
-        // This actually does more than calculate damage - it also sets up
-        // messages, etc.
-        player_calc_hit_damage();
+        const bool shield_blocked = attack_shield_blocked(true);
+
+        if (shield_blocked)
+            damage_done = 0;
+        else
+        {
+            // This actually does more than calculate damage - it also sets up
+            // messages, etc.
+            player_calc_hit_damage();
+        }
 
         bool hit_woke_orc = false;
         if (you.religion == GOD_BEOGH && mons_species(def->type) == MONS_ORC
@@ -564,7 +571,7 @@ bool melee_attack::player_attack()
 
         if (damage_done > 0 || !defender_visible)
             player_announce_hit();
-        else if (damage_done <= 0)
+        else if (!shield_blocked && damage_done <= 0)
             no_damage_message =
                 make_stringf("You %s %s.",
                              attack_verb.c_str(),
@@ -584,6 +591,10 @@ bool melee_attack::player_attack()
         }
 
         player_sustain_passive_damage();
+
+        // At this point, pretend we didn't hit at all.
+        if (shield_blocked)
+            did_hit = false;
     }
     else
         player_warn_miss();
@@ -854,6 +865,8 @@ bool melee_attack::player_aux_unarmed()
         did_hit = false;
         if (to_hit >= def->ev || one_chance_in(30))
         {
+            if (attack_shield_blocked(true))
+                continue;
             if (player_apply_aux_unarmed())
                 return (true);
         }
@@ -2865,8 +2878,8 @@ bool melee_attack::attack_shield_blocked(bool verbose)
         pro_block /= 3;
     
 #ifdef DEBUG_DIAGNOSTICS
-    mprf(MSGCH_DIAGNOSTICS, "Pro-block: %d, Con-block: %d",
-         pro_block, con_block);
+    mprf(MSGCH_DIAGNOSTICS, "Defender: %s, Pro-block: %d, Con-block: %d",
+         def_name(DESC_PLAIN).c_str(), pro_block, con_block);
 #endif
 
     if (pro_block >= con_block)
diff --git a/crawl-ref/source/makeitem.cc b/crawl-ref/source/makeitem.cc
index 2fef1653bf..e0a5e70030 100644
--- a/crawl-ref/source/makeitem.cc
+++ b/crawl-ref/source/makeitem.cc
@@ -3222,12 +3222,12 @@ static item_make_species_type give_weapon(monsters *mon, int level,
 
         const int temp_rand = random2(100);
         item.sub_type = ((temp_rand > 79) ? WPN_LONG_SWORD :    // 20%
-                             (temp_rand > 59) ? WPN_SHORT_SWORD :   // 20%
-                             (temp_rand > 45) ? WPN_SCIMITAR :      // 14%
-                             (temp_rand > 31) ? WPN_MACE :          // 14%
-                             (temp_rand > 18) ? WPN_BOW :           // 13%
-                             (temp_rand >  5) ? WPN_HAND_CROSSBOW   // 13%
-                                              : WPN_LONGBOW);       //  6%
+                         (temp_rand > 59) ? WPN_SHORT_SWORD :   // 20%
+                         (temp_rand > 45) ? WPN_SCIMITAR :      // 14%
+                         (temp_rand > 31) ? WPN_MACE :          // 14%
+                         (temp_rand > 18) ? WPN_BOW :           // 13%
+                         (temp_rand >  5) ? WPN_HAND_CROSSBOW   // 13%
+                         : WPN_LONGBOW);       //  6%
         break;
     }
 
@@ -3830,6 +3830,78 @@ static void give_ammo(monsters *mon, int level,
     }
 }
 
+static bool make_item_for_monster(
+    monsters *mons,
+    object_class_type base,
+    int subtype,
+    int level,
+    item_make_species_type race = MAKE_ITEM_NO_RACE,
+    int allow_uniques = 0)
+{
+    const int bp = get_item_slot();
+    if (bp == NON_ITEM)
+        return (false);
+
+    const int thing_created =
+        items( allow_uniques, base, subtype, true, level, race );
+
+    if (thing_created == NON_ITEM)
+        return (false);
+
+    give_monster_item(mons, thing_created);
+    return (true);
+}
+
+void give_shield(monsters *mon, int level)
+{
+    switch (mon->type)
+    {
+    case MONS_DAEVA:
+        make_item_for_monster(mon, OBJ_ARMOUR, ARM_LARGE_SHIELD,
+                              level * 2 + 1, MAKE_ITEM_RANDOM_RACE, 1);
+        break;
+        
+    case MONS_DEEP_ELF_SOLDIER:
+    case MONS_DEEP_ELF_FIGHTER:
+        if (one_chance_in(5))
+            make_item_for_monster(mon, OBJ_ARMOUR, ARM_BUCKLER,
+                                  level, MAKE_ITEM_ELVEN);
+        break;
+    case MONS_NAGA_WARRIOR:
+    case MONS_VAULT_GUARD:
+        if (one_chance_in(3))
+            make_item_for_monster(mon, OBJ_ARMOUR,
+                                  one_chance_in(3)? ARM_LARGE_SHIELD
+                                  : ARM_SHIELD,
+                                  level, MAKE_ITEM_NO_RACE);
+        break;
+    case MONS_DRACONIAN_KNIGHT:
+        if (coinflip())
+            make_item_for_monster(mon, OBJ_ARMOUR,
+                                  coinflip()? ARM_LARGE_SHIELD : ARM_SHIELD,
+                                  level, MAKE_ITEM_NO_RACE);
+        break;
+    case MONS_DEEP_ELF_KNIGHT:
+        if (coinflip())
+            make_item_for_monster(mon, OBJ_ARMOUR, ARM_BUCKLER,
+                                  level, MAKE_ITEM_ELVEN);
+        break;
+    case MONS_NORRIS:
+        make_item_for_monster(mon, OBJ_ARMOUR, ARM_BUCKLER,
+                              level * 2 + 1, MAKE_ITEM_RANDOM_RACE, 1);
+        break;
+    case MONS_NORBERT:
+    case MONS_LOUISE:
+        make_item_for_monster(mon, OBJ_ARMOUR, ARM_LARGE_SHIELD,
+                              level * 2 + 1, MAKE_ITEM_RANDOM_RACE, 1);
+        break;
+    case MONS_DONALD:
+        make_item_for_monster(mon, OBJ_ARMOUR, ARM_SHIELD,
+                              level * 2 + 1, MAKE_ITEM_RANDOM_RACE, 1);
+        break;
+    }
+}
+
 void give_armour(monsters *mon, int level)
 {
     const int bp = get_item_slot();
@@ -4071,6 +4143,7 @@ void give_item(int mid, int level_number) //mv: cleanup+minor changes
     
     give_ammo(mons, level_number, item_race);
     give_armour(mons, 1 + level_number / 2);
+    give_shield(mons, 1 + level_number / 2);
 }                               // end give_item()
 
 jewellery_type get_random_amulet_type()
diff --git a/crawl-ref/source/mon-util.cc b/crawl-ref/source/mon-util.cc
index 5cf5aa1168..84e27d4843 100644
--- a/crawl-ref/source/mon-util.cc
+++ b/crawl-ref/source/mon-util.cc
@@ -2765,14 +2765,19 @@ void monsters::equip_armour(item_def &item, int near)
         mprf("%s wears %s.", name(DESC_CAP_THE).c_str(),
              item.name(DESC_NOCAP_A).c_str());
 
-    ac += property( item, PARM_AC );
+    const equipment_type eq = get_armour_slot(item);
+    if (eq != EQ_SHIELD)
+    {
+        ac += property( item, PARM_AC );
+
+        const int armour_plus = item.plus;
+        ASSERT(abs(armour_plus) < 20);
+        if (abs(armour_plus) < 20)
+            ac += armour_plus;
+    }
 
-    const int armour_plus = item.plus;
-    ASSERT(abs(armour_plus) < 20);
-    if (abs(armour_plus) < 20) 
-        ac += armour_plus;
+    // Shields can affect evasion.
     ev += property( item, PARM_EVASION ) / 2;
-        
     if (ev < 1)
         ev = 1;   // This *shouldn't* happen.
 }
@@ -2842,14 +2847,18 @@ void monsters::unequip_armour(item_def &item, int near)
         mprf("%s takes off %s.", name(DESC_CAP_THE).c_str(),
              item.name(DESC_NOCAP_A).c_str());
 
-    ac -= property( item, PARM_AC );
+    const equipment_type eq = get_armour_slot(item);
+    if (eq != EQ_SHIELD)
+    {
+        ac -= property( item, PARM_AC );
 
-    const int armour_plus = item.plus;
-    ASSERT(abs(armour_plus) < 20);
-    if (abs(armour_plus) < 20) 
-        ac -= armour_plus;
+        const int armour_plus = item.plus;
+        ASSERT(abs(armour_plus) < 20);
+        if (abs(armour_plus) < 20) 
+            ac -= armour_plus;
+    }
+    
     ev -= property( item, PARM_EVASION ) / 2;
-        
     if (ev < 1)
         ev = 1;   // This *shouldn't* happen.
 }
@@ -3107,6 +3116,17 @@ bool monsters::wants_armour(const item_def &item) const
     return (!mslot_item(MSLOT_ARMOUR));
 }
 
+static mon_inv_type equip_slot_to_mslot(equipment_type eq)
+{
+    switch (eq)
+    {
+    case EQ_WEAPON: return MSLOT_WEAPON;
+    case EQ_BODY_ARMOUR: return MSLOT_ARMOUR;
+    case EQ_SHIELD: return MSLOT_SHIELD;
+    default: return (NUM_MONSTER_SLOTS);
+    }
+}
+
 bool monsters::pickup_armour(item_def &item, int near, bool force)
 {
     ASSERT(item.base_type == OBJ_ARMOUR);
@@ -3114,21 +3134,24 @@ bool monsters::pickup_armour(item_def &item, int near, bool force)
     if (!force && !wants_armour(item))
         return (false);
 
-    // XXX: Monsters can only equip body armour (as of 0.3).
-    if (get_armour_slot(item) != EQ_BODY_ARMOUR)
+    const equipment_type eq = get_armour_slot(item);
+    // XXX: Monsters can only equip body armour and shields (as of 0.4).
+    // They can still be forced to wear stuff - this is needed for bardings.
+    if (!force && eq != EQ_BODY_ARMOUR && eq != EQ_SHIELD)
         return (false);
 
+    const mon_inv_type mslot = equip_slot_to_mslot(eq);
     // XXX: Very simplistic armour evaluation for the moment.
-    if (const item_def *existing_armour = slot_item(EQ_BODY_ARMOUR))
+    if (const item_def *existing_armour = slot_item(eq))
     {
         if (!force && existing_armour->armour_rating() >= item.armour_rating())
             return (false);
 
-        if (!drop_item(MSLOT_ARMOUR, near))
+        if (!drop_item(mslot, near))
             return (false);
     }
 
-    return pickup(item, MSLOT_ARMOUR, near);
+    return pickup(item, mslot, near);
 }
 
 bool monsters::pickup_weapon(item_def &item, int near, bool force)
@@ -3302,16 +3325,6 @@ void monsters::wield_melee_weapon(int near)
     }
 }
 
-static mon_inv_type equip_slot_to_mslot(equipment_type eq)
-{
-    switch (eq)
-    {
-    case EQ_WEAPON: return MSLOT_WEAPON;
-    case EQ_BODY_ARMOUR: return MSLOT_ARMOUR;
-    default: return (NUM_MONSTER_SLOTS);
-    }
-}
-
 item_def *monsters::slot_item(equipment_type eq)
 {
     return mslot_item(equip_slot_to_mslot(eq));
@@ -3325,7 +3338,7 @@ item_def *monsters::mslot_item(mon_inv_type mslot) const
 
 item_def *monsters::shield()
 {
-    return (NULL);
+    return (mslot_item(MSLOT_SHIELD));
 }
 
 std::string monsters::name(description_level_type desc) const
@@ -3465,12 +3478,11 @@ bool monsters::caught() const
 
 int monsters::shield_bonus() const
 {
-    // XXX: Monsters don't actually get shields yet.
     const item_def *shld = const_cast<monsters*>(this)->shield();
     if (shld)
     {
         const int shld_c = property(*shld, PARM_AC);
-        return (random2(shld_c + random2(hit_dice / 2)) / 2);
+        return (random2(1 + shld_c) + random2(hit_dice / 2));
     }
     return (-100);
 }