github issue #1060 - crystal helmet

Issue reported by vultur-cadens:  changing helm of brilliance to
crystal made it stop being classified as "hard helmet" so it gave
less protection against things falling onto the hero's head.

Change the is_metallic() tests used on helmets to new hard_helmet().
Unlike when thrown, crystal helmets don't break when objects fall
on them.

Fixes #1060

src/ball.c

@@ -55,7 +55,7 @@ ballfall(void)
 
         pline_The("iron ball falls on your %s.", body_part(HEAD));
         if (uarmh) {
-            if (is_metallic(uarmh)) {
+            if (hard_helmet(uarmh)) {
                 pline("Fortunately, you are wearing a hard helmet.");
                 dmg = 3;
             } else if (Verbose(0, ballfall))

src/dig.c

@@ -1459,7 +1459,7 @@ zap_dig(void)
                 }
                 You("loosen a rock from the %s.", ceiling(u.ux, u.uy));
                 pline("It falls on your %s!", body_part(HEAD));
-                dmg = rnd((uarmh && is_metallic(uarmh)) ? 2 : 6);
+                dmg = rnd(hard_helmet(uarmh) ? 2 : 6);
                 losehp(Maybe_Half_Phys(dmg), "falling rock", KILLED_BY_AN);
                 otmp = mksobj_at(ROCK, u.ux, u.uy, FALSE, FALSE);
                 if (otmp) {

src/do_wear.c

@@ -512,6 +512,30 @@ Helmet_off(void)
     return 0;
 }
 
+/* hard helms provide better protection against against falling rocks */
+boolean
+hard_helmet(struct obj *obj)
+{
+    static const char crystal_[] = "crystal ";
+    const char *ostr;
+    int otyp;
+
+    if (!obj || !is_helmet(obj))
+        return FALSE;
+    if (is_metallic(obj))
+        return TRUE;
+    /* make helm of brilliance (crystal helmet) be classified 'hard'; this
+       test would work for crystal plate mail too if suits reached here */
+    otyp = obj->otyp;
+    if (objects[otyp].oc_material == GLASS
+        && (((ostr = OBJ_NAME(objects[otyp])) != 0
+             && !strncmp(ostr, crystal_, 8))
+            || ((ostr = OBJ_DESCR(objects[otyp])) != 0
+                && !strncmp(ostr, crystal_, 8))))
+        return TRUE;
+    return FALSE;
+}
+
 static int
 Gloves_on(void)
 {

src/dothrow.c

@@ -1334,7 +1334,7 @@ toss_up(struct obj *obj, boolean hitsroof)
     } else { /* neither potion nor other breaking object */
         int material = objects[otyp].oc_material;
         boolean is_silver = (material == SILVER),
-                less_damage = (uarmh && is_metallic(uarmh)
+                less_damage = (hard_helmet(uarmh)
                                && (!is_silver || !Hate_silver)),
                 harmless = (stone_missile(obj)
                             && passes_rocks(gy.youmonst.data)),

src/hack.c

@@ -2945,7 +2945,7 @@ spoteffects(boolean pick)
                   ceiling(u.ux, u.uy));
             if (mtmp->mtame) { /* jumps to greet you, not attack */
                 ;
-            } else if (uarmh && is_metallic(uarmh)) {
+            } else if (hard_helmet(uarmh)) {
                 pline("Its blow glances off your %s.",
                       helm_simple_name(uarmh));
             } else if (u.uac + 3 <= rnd(20)) {

src/mhitu.c

@@ -526,7 +526,7 @@ mattacku(register struct monst *mtmp)
                 return 0; /* lurkers don't attack */
 
             obj = which_armor(mtmp, WORN_HELMET);
-            if (obj && is_metallic(obj)) {
+            if (hard_helmet(obj)) {
                 Your("blow glances off %s %s.", s_suffix(mon_nam(mtmp)),
                      helm_simple_name(obj));
             } else {

src/muse.c

@@ -1430,7 +1430,7 @@ find_offensive(struct monst *mtmp)
          */
         nomore(MUSE_SCR_EARTH);
         if (obj->otyp == SCR_EARTH
-            && ((helmet && is_metallic(helmet)) || mtmp->mconf
+            && (hard_helmet(helmet) || mtmp->mconf
                 || amorphous(mtmp->data) || passes_walls(mtmp->data)
                 || noncorporeal(mtmp->data) || unsolid(mtmp->data)
                 || !rn2(10))
@@ -1875,7 +1875,7 @@ rnd_offensive_item(struct monst *mtmp)
     case 0: {
         struct obj *helmet = which_armor(mtmp, W_ARMH);
 
-        if ((helmet && is_metallic(helmet)) || amorphous(pm)
+        if (hard_helmet(helmet) || amorphous(pm)
             || passes_walls(pm) || noncorporeal(pm) || unsolid(pm))
             return SCR_EARTH;
     } /* fall through */

src/objnam.c

@@ -5095,7 +5095,7 @@ helm_simple_name(struct obj *helmet)
      *      fedora, cornuthaum, dunce cap       -> hat
      *      all other types of helmets          -> helm
      */
-    return (helmet && !is_metallic(helmet)) ? "hat" : "helm";
+    return !hard_helmet(helmet) ? "hat" : "helm";
 }
 
 /* gloves vs gauntlets; depends upon discovery state */

src/potion.c

@@ -1173,7 +1173,7 @@ peffect_levitation(struct obj *otmp)
                resulted in incrementing 'nothing' */
             gp.potion_nothing = 0; /* not nothing after all */
         } else if (has_ceiling(&u.uz)) {
-            int dmg = rnd(!uarmh ? 10 : !is_metallic(uarmh) ? 6 : 3);
+            int dmg = rnd(!uarmh ? 10 : !hard_helmet(uarmh) ? 6 : 3);
 
             You("hit your %s on the %s.", body_part(HEAD),
                 ceiling(u.ux, u.uy));

src/read.c

@@ -2164,7 +2164,11 @@ seffects(struct obj *sobj) /* sobj - scroll or fake spellbook for spell */
 }
 
 void
-drop_boulder_on_player(boolean confused, boolean helmet_protects, boolean byu, boolean skip_uswallow)
+drop_boulder_on_player(
+    boolean confused,
+    boolean helmet_protects,
+    boolean byu,
+    boolean skip_uswallow)
 {
     int dmg;
     struct obj *otmp2;
@@ -2185,7 +2189,7 @@ drop_boulder_on_player(boolean confused, boolean helmet_protects, boolean byu, b
         You("are hit by %s!", doname(otmp2));
         dmg = (int) (dmgval(otmp2, &gy.youmonst) * otmp2->quan);
         if (uarmh && helmet_protects) {
-            if (is_metallic(uarmh)) {
+            if (hard_helmet(uarmh)) {
                 pline("Fortunately, you are wearing a hard helmet.");
                 if (dmg > 2)
                     dmg = 2;
@@ -2237,7 +2241,7 @@ drop_boulder_on_monster(coordxy x, coordxy y, boolean confused, boolean byu)
 
         mdmg = dmgval(otmp2, mtmp) * otmp2->quan;
         if (helmet) {
-            if (is_metallic(helmet)) {
+            if (hard_helmet(helmet)) {
                 if (canspotmon(mtmp))
                     pline("Fortunately, %s is wearing a hard helmet.",
                           mon_nam(mtmp));

src/trap.c

@@ -1197,7 +1197,7 @@ trapeffect_rocktrap(
                     pline("Unfortunately, you are wearing %s.",
                           an(helm_simple_name(uarmh))); /* helm or hat */
                     dmg = 2;
-                } else if (is_metallic(uarmh)) {
+                } else if (hard_helmet(uarmh)) {
                     pline("Fortunately, you are wearing a hard helmet.");
                     dmg = 2;
                 } else if (Verbose(3, trapeffect_rocktrap)) {

src/zap.c

@@ -3148,7 +3148,7 @@ zap_updown(struct obj *obj) /* wand or spell */
             /* similar to zap_dig() */
             pline("A rock is dislodged from the %s and falls on your %s.",
                   ceiling(x, y), body_part(HEAD));
-            dmg = rnd((uarmh && is_metallic(uarmh)) ? 2 : 6);
+            dmg = rnd(hard_helmet(uarmh) ? 2 : 6);
             losehp(Maybe_Half_Phys(dmg), "falling rock", KILLED_BY_AN);
             if ((otmp = mksobj_at(ROCK, x, y, FALSE, FALSE)) != 0) {
                 (void) xname(otmp); /* set dknown, maybe bknown */