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[Fix] #280 player-status-flags.c 内で論理和計算すべきところを即値代入しているミスを修正. / Corrected a mistake...
[hengbandforosx/hengbandosx.git] / src / player / player-status-flags.c
index 646a478..0d61858 100644 (file)
@@ -1,5 +1,5 @@
 #include "player/player-status-flags.h"
-#include "art-definition/art-sword-types.h"
+#include "artifact/fixed-art-types.h"
 #include "grid/grid.h"
 #include "inventory/inventory-slot-types.h"
 #include "monster-race/monster-race.h"
 #include "object-hook/hook-checker.h"
 #include "object-hook/hook-weapon.h"
 #include "object/object-flags.h"
+#include "player/mimic-info-table.h"
 #include "player/player-class.h"
 #include "player/player-race-types.h"
 #include "player/player-race.h"
 #include "player/player-skill.h"
 #include "player/player-status.h"
+#include "player/race-info-table.h"
 #include "player/special-defense-types.h"
 #include "realm/realm-hex-numbers.h"
 #include "realm/realm-song-numbers.h"
 #include "util/quarks.h"
 #include "util/string-processor.h"
 
-bool have_kill_wall(player_type *creature_ptr)
+static BIT_FLAGS check_equipment_flags(player_type *creature_ptr, tr_type tr_flag);
+
+/*!
+ * @brief 装備による所定の特性フラグを得ているかを一括して取得する関数。
+ */
+static BIT_FLAGS check_equipment_flags(player_type *creature_ptr, tr_type tr_flag)
+{
+    object_type *o_ptr;
+    BIT_FLAGS flgs[TR_FLAG_SIZE];
+    BIT_FLAGS result = 0L;
+    for (inventory_slot_type i = INVEN_MAIN_HAND; i < INVEN_TOTAL; i++) {
+        o_ptr = &creature_ptr->inventory_list[i];
+        if (!o_ptr->k_idx)
+            continue;
+
+        object_flags(creature_ptr, o_ptr, flgs);
+
+        if (has_flag(flgs, tr_flag))
+            result |= 0x01U << (i - INVEN_MAIN_HAND);
+    }
+    return result;
+}
+
+/*!
+ * @brief クリーチャーが壁破壊進行を持っているかを返す。
+ */
+bool has_kill_wall(player_type *creature_ptr)
 {
     if (creature_ptr->mimic_form == MIMIC_DEMON_LORD || music_singing(creature_ptr, MUSIC_WALL)) {
         return TRUE;
@@ -43,10 +71,18 @@ bool have_kill_wall(player_type *creature_ptr)
             return TRUE;
     }
 
-       return FALSE;
+    return FALSE;
 }
 
-bool have_pass_wall(player_type *creature_ptr)
+/*!
+ * @brief クリーチャーが壁通過を持っているかを返す。
+ * @param creature_ptr 判定対象のクリーチャー参照ポインタ
+ * @return 持っていたらTRUE
+ * @details
+ * * 時限で幽体化、壁抜けをもつか種族幽霊ならばひとまずTRUE。
+ * * 但し騎乗中は乗騎が壁抜けを持っていなければ不能になる。
+ */
+bool has_pass_wall(player_type *creature_ptr)
 {
     bool pow = FALSE;
 
@@ -61,406 +97,210 @@ bool have_pass_wall(player_type *creature_ptr)
             pow = FALSE;
     }
 
-       return pow;
-}
-
-BIT_FLAGS have_xtra_might(player_type *creature_ptr)
-{
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
-    BIT_FLAGS result = 0L;
-
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
-
-        object_flags(creature_ptr, o_ptr, flgs);
-
-        if (have_flag(flgs, TR_XTRA_MIGHT))
-            result |= 0x01 << (i - INVEN_RARM);
-    }
-
-       return result;
-}
-
-BIT_FLAGS have_esp_evil(player_type *creature_ptr)
-{
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
-    BIT_FLAGS result = 0L;
-
-    if (creature_ptr->realm1 == REALM_HEX) {
-        if (hex_spelling(creature_ptr, HEX_DETECT_EVIL))
-            result |= 0x01 << FLAG_CAUSE_MAGIC_TIME_EFFECT;
-    }
-
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
-
-        object_flags(creature_ptr, o_ptr, flgs);
-
-        if (have_flag(flgs, TR_ESP_EVIL))
-            result |= 0x01 << (i - INVEN_RARM);
-    }
-
-       return result;
+    return pow;
 }
 
-BIT_FLAGS have_esp_animal(player_type *creature_ptr)
+/*!
+ * @brief クリーチャーが強力射を持っているかを返す。
+ * @param creature_ptr 判定対象のクリーチャー参照ポインタ
+ * @return 持っていたら所持前提ビットフラグを返す。
+ */
+BIT_FLAGS has_xtra_might(player_type *creature_ptr)
 {
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
     BIT_FLAGS result = 0L;
-
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
-
-        object_flags(creature_ptr, o_ptr, flgs);
-
-        if (have_flag(flgs, TR_ESP_ANIMAL))
-            result |= 0x01 << (i - INVEN_RARM);
-    }
-
-       return result;
+    result |= check_equipment_flags(creature_ptr, TR_XTRA_MIGHT);
+    return result;
 }
 
-BIT_FLAGS have_esp_undead(player_type *creature_ptr)
+/*!
+ * @brief クリーチャーが赤外線視力修正を持っているかを返す。
+ * @param creature_ptr 判定対象のクリーチャー参照ポインタ
+ * @return 持っていたら所持前提ビットフラグを返す。
+ * @details 種族修正は0より大きければTRUEとする。
+ */
+BIT_FLAGS has_infra_vision(player_type *creature_ptr)
 {
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
     BIT_FLAGS result = 0L;
+    const player_race *tmp_rp_ptr;
 
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
-
-        object_flags(creature_ptr, o_ptr, flgs);
+    if (creature_ptr->mimic_form)
+        tmp_rp_ptr = &mimic_info[creature_ptr->mimic_form];
+    else
+        tmp_rp_ptr = &race_info[creature_ptr->prace];
 
-        if (have_flag(flgs, TR_ESP_UNDEAD))
-            result |= 0x01 << (i - INVEN_RARM);
-    }
+    if (tmp_rp_ptr->infra > 0)
+        result |= FLAG_CAUSE_RACE;
 
-       return result;
-}
+    if (creature_ptr->muta3 & MUT3_INFRAVIS)
+        result |= FLAG_CAUSE_MUTATION;
 
-BIT_FLAGS have_esp_demon(player_type *creature_ptr)
-{
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
-    BIT_FLAGS result = 0L;
+    if (creature_ptr->tim_infra)
+        result |= FLAG_CAUSE_MAGIC_TIME_EFFECT;
 
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
-
-        object_flags(creature_ptr, o_ptr, flgs);
-
-        if (have_flag(flgs, TR_ESP_DEMON))
-            result |= 0x01 << (i - INVEN_RARM);
-    }
-
-       return result;
+    result |= check_equipment_flags(creature_ptr, TR_INFRA);
+    return result;
 }
 
-BIT_FLAGS have_esp_orc(player_type *creature_ptr)
+/*!
+ * @brief クリーチャーが邪悪感知を持っているかを返す。
+ * @param creature_ptr 判定対象のクリーチャー参照ポインタ
+ * @return 持っていたら所持前提ビットフラグを返す。
+ */
+BIT_FLAGS has_esp_evil(player_type *creature_ptr)
 {
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
     BIT_FLAGS result = 0L;
-
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
-
-        object_flags(creature_ptr, o_ptr, flgs);
-
-        if (have_flag(flgs, TR_ESP_ORC))
-            result |= 0x01 << (i - INVEN_RARM);
-    }
-
-       return result;
-}
-
-BIT_FLAGS have_esp_troll(player_type *creature_ptr)
-{
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
-    BIT_FLAGS result = 0L;
-
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
-
-        object_flags(creature_ptr, o_ptr, flgs);
-
-        if (have_flag(flgs, TR_ESP_TROLL))
-            result |= 0x01 << (i - INVEN_RARM);
-    }
-
-       return result;
-}
-
-BIT_FLAGS have_esp_giant(player_type *creature_ptr)
+    if (creature_ptr->realm1 == REALM_HEX) {
+        if (hex_spelling(creature_ptr, HEX_DETECT_EVIL))
+            result |= 0x01U << FLAG_CAUSE_MAGIC_TIME_EFFECT;
+    }
+    result |= check_equipment_flags(creature_ptr, TR_ESP_EVIL);
+    return result;
+}
+
+/*!
+ * @brief クリーチャーが自然界の動物感知を持っているかを返す。
+ * @param creature_ptr 判定対象のクリーチャー参照ポインタ
+ * @return 持っていたら所持前提ビットフラグを返す。
+ */
+BIT_FLAGS has_esp_animal(player_type *creature_ptr) { return check_equipment_flags(creature_ptr, TR_ESP_ANIMAL); }
+
+/*!
+ * @brief クリーチャーがアンデッド感知を持っているかを返す。
+ * @param creature_ptr 判定対象のクリーチャー参照ポインタ
+ * @return 持っていたら所持前提ビットフラグを返す。
+ */
+BIT_FLAGS has_esp_undead(player_type *creature_ptr) { return check_equipment_flags(creature_ptr, TR_ESP_UNDEAD); }
+
+/*!
+ * @brief クリーチャーが悪魔感知を持っているかを返す。
+ * @param creature_ptr 判定対象のクリーチャー参照ポインタ
+ * @return 持っていたら所持前提ビットフラグを返す。
+ */
+BIT_FLAGS has_esp_demon(player_type *creature_ptr) { return check_equipment_flags(creature_ptr, TR_ESP_DEMON); }
+
+/*!
+ * @brief クリーチャーがオーク感知を持っているかを返す。
+ * @param creature_ptr 判定対象のクリーチャー参照ポインタ
+ * @return 持っていたら所持前提ビットフラグを返す。
+ */
+BIT_FLAGS has_esp_orc(player_type *creature_ptr) { return check_equipment_flags(creature_ptr, TR_ESP_ORC); }
+
+/*!
+ * @brief クリーチャーがトロル感知を持っているかを返す。
+ * @param creature_ptr 判定対象のクリーチャー参照ポインタ
+ * @return 持っていたら所持前提ビットフラグを返す。
+ */
+BIT_FLAGS has_esp_troll(player_type *creature_ptr) { return check_equipment_flags(creature_ptr, TR_ESP_TROLL); }
+
+/*!
+ * @brief クリーチャーが巨人感知を持っているかを返す。
+ * @param creature_ptr 判定対象のクリーチャー参照ポインタ
+ * @return 持っていたら所持前提ビットフラグを返す。
+ */
+BIT_FLAGS has_esp_giant(player_type *creature_ptr) { return check_equipment_flags(creature_ptr, TR_ESP_GIANT); }
+
+/*!
+ * @brief クリーチャーがドラゴン感知を持っているかを返す。
+ * @param creature_ptr 判定対象のクリーチャー参照ポインタ
+ * @return 持っていたら所持前提ビットフラグを返す。
+ */
+BIT_FLAGS has_esp_dragon(player_type *creature_ptr) { return check_equipment_flags(creature_ptr, TR_ESP_DRAGON); }
+
+/*!
+ * @brief クリーチャーが人間感知を持っているかを返す。
+ * @param creature_ptr 判定対象のクリーチャー参照ポインタ
+ * @return 持っていたら所持前提ビットフラグを返す。
+ */
+BIT_FLAGS has_esp_human(player_type *creature_ptr) { return check_equipment_flags(creature_ptr, TR_ESP_HUMAN); }
+
+/*!
+ * @brief クリーチャーが善良感知を持っているかを返す。
+ * @param creature_ptr 判定対象のクリーチャー参照ポインタ
+ * @return 持っていたら所持前提ビットフラグを返す。
+ */
+BIT_FLAGS has_esp_good(player_type *creature_ptr) { return check_equipment_flags(creature_ptr, TR_ESP_GOOD); }
+
+/*!
+ * @brief クリーチャーが無生物感知を持っているかを返す。
+ * @param creature_ptr 判定対象のクリーチャー参照ポインタ
+ * @return 持っていたら所持前提ビットフラグを返す。
+ */
+BIT_FLAGS has_esp_nonliving(player_type *creature_ptr) { return check_equipment_flags(creature_ptr, TR_ESP_NONLIVING); }
+
+/*!
+ * @brief クリーチャーがユニーク感知を持っているかを返す。
+ * @param creature_ptr 判定対象のクリーチャー参照ポインタ
+ * @return 持っていたら所持前提ビットフラグを返す。
+ */
+BIT_FLAGS has_esp_unique(player_type *creature_ptr) { return check_equipment_flags(creature_ptr, TR_ESP_UNIQUE); }
+
+/*!
+ * @brief クリーチャーがテレパシーを持っているかを返す。
+ * @param creature_ptr 判定対象のクリーチャー参照ポインタ
+ * @return 持っていたら所持前提ビットフラグを返す。
+ */
+BIT_FLAGS has_esp_telepathy(player_type *creature_ptr)
 {
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
     BIT_FLAGS result = 0L;
 
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
-
-        object_flags(creature_ptr, o_ptr, flgs);
-
-        if (have_flag(flgs, TR_ESP_GIANT))
-            result |= 0x01 << (i - INVEN_RARM);
-    }
-
-       return result;
-}
-
-BIT_FLAGS have_esp_dragon(player_type *creature_ptr)
-{
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
-    BIT_FLAGS result = 0L;
-
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
-
-        object_flags(creature_ptr, o_ptr, flgs);
-
-        if (have_flag(flgs, TR_ESP_DRAGON))
-            result |= 0x01 << (i - INVEN_RARM);
-    }
-
-       return result;
-}
-
-void have_esp_human(player_type *creature_ptr)
-{
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
-
-    creature_ptr->esp_human = FALSE;
-
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
-
-        object_flags(creature_ptr, o_ptr, flgs);
-
-        if (have_flag(flgs, TR_ESP_HUMAN))
-            creature_ptr->esp_human = TRUE;
-    }
-}
-
-void have_esp_good(player_type *creature_ptr)
-{
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
-
-    creature_ptr->esp_good = FALSE;
-
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
-
-        object_flags(creature_ptr, o_ptr, flgs);
-
-        if (have_flag(flgs, TR_ESP_GOOD))
-            creature_ptr->esp_good = TRUE;
-    }
-}
-
-void have_esp_nonliving(player_type *creature_ptr)
-{
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
-
-    creature_ptr->esp_nonliving = FALSE;
-
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
-
-        object_flags(creature_ptr, o_ptr, flgs);
-
-        if (have_flag(flgs, TR_ESP_NONLIVING))
-            creature_ptr->esp_nonliving = TRUE;
-    }
-}
-
-void have_esp_unique(player_type *creature_ptr)
-{
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
-
-    creature_ptr->esp_unique = FALSE;
-
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
-
-        object_flags(creature_ptr, o_ptr, flgs);
-
-        if (have_flag(flgs, TR_ESP_UNIQUE))
-            creature_ptr->esp_unique = TRUE;
-    }
-}
-
-void have_esp_telepathy(player_type *creature_ptr)
-{
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
-
-    creature_ptr->telepathy = FALSE;
-
-    if (is_time_limit_esp(creature_ptr)) {
-        creature_ptr->telepathy = TRUE;
+    if (is_time_limit_esp(creature_ptr) || creature_ptr->ult_res || (creature_ptr->special_defense & KATA_MUSOU)) {
+        result |= 0x01U << FLAG_CAUSE_MAGIC_TIME_EFFECT;
     }
 
     if (creature_ptr->muta3 & MUT3_ESP) {
-        creature_ptr->telepathy = TRUE;
+        result |= 0x01U << FLAG_CAUSE_MUTATION;
     }
 
-    if (!creature_ptr->mimic_form && creature_ptr->prace == RACE_MIND_FLAYER && creature_ptr->lev > 29)
-        creature_ptr->telepathy = TRUE;
+    if (is_specific_player_race(creature_ptr, RACE_MIND_FLAYER) && creature_ptr->lev > 29)
+        result |= 0x01U << FLAG_CAUSE_RACE;
 
-    if (!creature_ptr->mimic_form && creature_ptr->prace == RACE_SPECTRE && creature_ptr->lev > 34)
-        creature_ptr->telepathy = TRUE;
+    if (is_specific_player_race(creature_ptr, RACE_SPECTRE) && creature_ptr->lev > 34)
+        result |= 0x01U << FLAG_CAUSE_RACE;
 
     if (creature_ptr->pclass == CLASS_MINDCRAFTER && creature_ptr->lev > 39)
-        creature_ptr->telepathy = TRUE;
+        result |= 0x01U << FLAG_CAUSE_CLASS;
 
     if (creature_ptr->mimic_form == MIMIC_DEMON_LORD) {
-        creature_ptr->telepathy = TRUE;
-    }
-
-    if (creature_ptr->ult_res || (creature_ptr->special_defense & KATA_MUSOU)) {
-        creature_ptr->telepathy = TRUE;
-    }
-
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
-
-        object_flags(creature_ptr, o_ptr, flgs);
-
-        if (have_flag(flgs, TR_TELEPATHY))
-            creature_ptr->telepathy = TRUE;
+        result |= 0x01U << FLAG_CAUSE_RACE;
     }
-}
-
-void have_bless_blade(player_type *creature_ptr)
-{
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
-
-    creature_ptr->bless_blade = FALSE;
-
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
-
-        object_flags(creature_ptr, o_ptr, flgs);
-
-        if (have_flag(flgs, TR_BLESSED))
-            creature_ptr->bless_blade = TRUE;
-    }
-}
-
-void have_easy2_weapon(player_type *creature_ptr)
-{
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
-
-    creature_ptr->easy_2weapon = FALSE;
-
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
 
-        object_flags(creature_ptr, o_ptr, flgs);
-
-        if (o_ptr->name2 == EGO_2WEAPON)
-            creature_ptr->easy_2weapon = TRUE;
-    }
+    result |= check_equipment_flags(creature_ptr, TR_TELEPATHY);
+    return result;
 }
 
-void have_down_saving(player_type *creature_ptr)
-{
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
+BIT_FLAGS has_bless_blade(player_type *creature_ptr) { return check_equipment_flags(creature_ptr, TR_BLESSED); }
 
-    creature_ptr->down_saving = FALSE;
+BIT_FLAGS has_easy2_weapon(player_type *creature_ptr) { return check_equipment_flags(creature_ptr, TR_EASY2_WEAPON); }
 
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
-
-        object_flags(creature_ptr, o_ptr, flgs);
+BIT_FLAGS has_down_saving(player_type *creature_ptr) { return check_equipment_flags(creature_ptr, TR_DOWN_SAVING); }
 
-        if (o_ptr->name2 == EGO_AMU_NAIVETY)
-            creature_ptr->down_saving = TRUE;
-    }
-}
+BIT_FLAGS has_no_ac(player_type *creature_ptr) { return check_equipment_flags(creature_ptr, TR_NO_AC); }
 
-void have_no_ac(player_type *creature_ptr)
+BIT_FLAGS has_invuln_arrow(player_type *creature_ptr)
 {
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
-
-    creature_ptr->yoiyami = FALSE;
-
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
-
-        object_flags(creature_ptr, o_ptr, flgs);
-
-        if (o_ptr->name2 == EGO_YOIYAMI)
-            creature_ptr->yoiyami = TRUE;
-    }
+    BIT_FLAGS result = 0L;
+    if (creature_ptr->blind)
+        return result;
+    result |= check_equipment_flags(creature_ptr, TR_INVULN_ARROW);
+    return result;
 }
 
-void have_no_flowed(player_type *creature_ptr)
+void check_no_flowed(player_type *creature_ptr)
 {
     object_type *o_ptr;
-    bool have_sw = FALSE, have_kabe = FALSE;
+    bool has_sw = FALSE, has_kabe = FALSE;
     OBJECT_IDX this_o_idx, next_o_idx = 0;
 
     creature_ptr->no_flowed = FALSE;
 
-    if (creature_ptr->pass_wall && !creature_ptr->kill_wall)
+    if (has_pass_wall(creature_ptr) && !has_kill_wall(creature_ptr))
         creature_ptr->no_flowed = TRUE;
 
     for (int i = 0; i < INVEN_PACK; i++) {
         if ((creature_ptr->inventory_list[i].tval == TV_NATURE_BOOK) && (creature_ptr->inventory_list[i].sval == 2))
-            have_sw = TRUE;
+            has_sw = TRUE;
         if ((creature_ptr->inventory_list[i].tval == TV_CRAFT_BOOK) && (creature_ptr->inventory_list[i].sval == 2))
-            have_kabe = TRUE;
+            has_kabe = TRUE;
     }
 
     for (this_o_idx = creature_ptr->current_floor_ptr->grid_array[creature_ptr->y][creature_ptr->x].o_idx; this_o_idx; this_o_idx = next_o_idx) {
@@ -468,672 +308,422 @@ void have_no_flowed(player_type *creature_ptr)
         next_o_idx = o_ptr->next_o_idx;
 
         if ((o_ptr->tval == TV_NATURE_BOOK) && (o_ptr->sval == 2))
-            have_sw = TRUE;
+            has_sw = TRUE;
         if ((o_ptr->tval == TV_CRAFT_BOOK) && (o_ptr->sval == 2))
-            have_kabe = TRUE;
+            has_kabe = TRUE;
     }
 
-    if (have_sw && ((creature_ptr->realm1 == REALM_NATURE) || (creature_ptr->realm2 == REALM_NATURE) || (creature_ptr->pclass == CLASS_SORCERER))) {
+    if (has_sw && ((creature_ptr->realm1 == REALM_NATURE) || (creature_ptr->realm2 == REALM_NATURE) || (creature_ptr->pclass == CLASS_SORCERER))) {
         const magic_type *s_ptr = &mp_ptr->info[REALM_NATURE - 1][SPELL_SW];
         if (creature_ptr->lev >= s_ptr->slevel)
             creature_ptr->no_flowed = TRUE;
     }
 
-    if (have_kabe && ((creature_ptr->realm1 == REALM_CRAFT) || (creature_ptr->realm2 == REALM_CRAFT) || (creature_ptr->pclass == CLASS_SORCERER))) {
+    if (has_kabe && ((creature_ptr->realm1 == REALM_CRAFT) || (creature_ptr->realm2 == REALM_CRAFT) || (creature_ptr->pclass == CLASS_SORCERER))) {
         const magic_type *s_ptr = &mp_ptr->info[REALM_CRAFT - 1][SPELL_WALL];
         if (creature_ptr->lev >= s_ptr->slevel)
             creature_ptr->no_flowed = TRUE;
     }
 }
 
-void have_mighty_throw(player_type *creature_ptr)
-{
-    object_type *o_ptr;
-
-    creature_ptr->mighty_throw = FALSE;
-
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
-
-        if (o_ptr->name2 == EGO_RING_THROW)
-            creature_ptr->mighty_throw = TRUE;
-    }
-}
-
-void have_dec_mana(player_type *creature_ptr)
-{
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
-
-    creature_ptr->xtra_might = FALSE;
-
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
+BIT_FLAGS has_mighty_throw(player_type *creature_ptr) { return check_equipment_flags(creature_ptr, TR_MIGHTY_THROW); }
 
-        object_flags(creature_ptr, o_ptr, flgs);
+BIT_FLAGS has_dec_mana(player_type *creature_ptr) { return check_equipment_flags(creature_ptr, TR_DEC_MANA); }
 
-        if (have_flag(flgs, TR_DEC_MANA))
-            creature_ptr->dec_mana = TRUE;
-    }
-}
-
-void have_reflect(player_type *creature_ptr)
+BIT_FLAGS has_reflect(player_type *creature_ptr)
 {
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
-
-    creature_ptr->reflect = FALSE;
+    BIT_FLAGS result = 0L;
 
     if (creature_ptr->pclass == CLASS_BERSERKER && creature_ptr->lev > 39)
-        creature_ptr->reflect = TRUE;
+        result |= 0x01U << FLAG_CAUSE_CLASS;
 
     if (creature_ptr->pclass == CLASS_MIRROR_MASTER && creature_ptr->lev > 39)
-        creature_ptr->reflect = TRUE;
-
-    if (creature_ptr->special_defense & KAMAE_GENBU) {
-        creature_ptr->reflect = TRUE;
-    }
-
-    if (creature_ptr->ult_res || (creature_ptr->special_defense & KATA_MUSOU)) {
-        creature_ptr->reflect = TRUE;
-    }
+        result |= 0x01U << FLAG_CAUSE_CLASS;
 
-    if (creature_ptr->wraith_form) {
-        creature_ptr->reflect = TRUE;
+    if (creature_ptr->special_defense & KAMAE_GENBU || creature_ptr->special_defense & KATA_MUSOU) {
+        result |= 0x01U << FLAG_CAUSE_BATTLE_FORM;
     }
 
-    if (creature_ptr->magicdef) {
-        creature_ptr->reflect = TRUE;
+    if (creature_ptr->ult_res || creature_ptr->wraith_form || creature_ptr->magicdef || creature_ptr->tim_reflect) {
+        result |= 0x01U << FLAG_CAUSE_MAGIC_TIME_EFFECT;
     }
 
-    if (creature_ptr->tim_reflect) {
-        creature_ptr->reflect = TRUE;
-    }
-
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
-
-        object_flags(creature_ptr, o_ptr, flgs);
-
-        if (have_flag(flgs, TR_REFLECT))
-            creature_ptr->reflect = TRUE;
-    }
+    result |= check_equipment_flags(creature_ptr, TR_REFLECT);
+    return result;
 }
 
-void have_see_nocto(player_type *creature_ptr)
-{
-    creature_ptr->see_nocto = FALSE;
+BIT_FLAGS has_see_nocto(player_type *creature_ptr) { return creature_ptr->pclass == CLASS_NINJA ? FLAG_CAUSE_CLASS : 0L; }
 
-    if (creature_ptr->pclass == CLASS_NINJA)
-        creature_ptr->see_nocto = TRUE;
-}
-
-void have_warning(player_type *creature_ptr)
-{
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
-
-    creature_ptr->warning = FALSE;
-
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
-
-        object_flags(creature_ptr, o_ptr, flgs);
-
-        if (have_flag(flgs, TR_WARNING)) {
-            if (!o_ptr->inscription || !(angband_strchr(quark_str(o_ptr->inscription), '$')))
-                creature_ptr->warning = TRUE;
-        }
-    }
-}
-
-void have_anti_magic(player_type *creature_ptr)
-{
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
-
-    creature_ptr->anti_magic = FALSE;
-
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
-
-        object_flags(creature_ptr, o_ptr, flgs);
-
-        if (have_flag(flgs, TR_NO_MAGIC))
-            creature_ptr->anti_magic = TRUE;
-    }
-}
-
-void have_anti_tele(player_type *creature_ptr)
+BIT_FLAGS has_warning(player_type *creature_ptr)
 {
+    BIT_FLAGS result = 0L;
     object_type *o_ptr;
     BIT_FLAGS flgs[TR_FLAG_SIZE];
 
-    creature_ptr->anti_tele = FALSE;
-
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
+    for (inventory_slot_type i = INVEN_MAIN_HAND; i < INVEN_TOTAL; i++) {
         o_ptr = &creature_ptr->inventory_list[i];
         if (!o_ptr->k_idx)
             continue;
 
         object_flags(creature_ptr, o_ptr, flgs);
 
-        if (have_flag(flgs, TR_NO_TELE))
-            creature_ptr->anti_tele = TRUE;
+        if (has_flag(flgs, TR_WARNING)) {
+            if (!o_ptr->inscription || !(angband_strchr(quark_str(o_ptr->inscription), '$')))
+                result |= 0x01U << (i - INVEN_MAIN_HAND);
+        }
     }
+    return result;
 }
 
-void have_sh_fire(player_type *creature_ptr)
+BIT_FLAGS has_anti_magic(player_type *creature_ptr) { return check_equipment_flags(creature_ptr, TR_NO_MAGIC); }
+
+BIT_FLAGS has_anti_tele(player_type *creature_ptr) { return check_equipment_flags(creature_ptr, TR_NO_TELE); }
+
+BIT_FLAGS has_sh_fire(player_type *creature_ptr)
 {
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
-    creature_ptr->sh_fire = FALSE;
+    BIT_FLAGS result = 0L;
 
     if (creature_ptr->muta3 & MUT3_FIRE_BODY) {
-        creature_ptr->sh_fire = TRUE;
+        result |= 0x01U << FLAG_CAUSE_MUTATION;
     }
 
     if (creature_ptr->mimic_form == MIMIC_DEMON_LORD) {
-        creature_ptr->sh_fire = TRUE;
+        result |= 0x01U << FLAG_CAUSE_RACE;
     }
 
-    if (creature_ptr->realm1 == REALM_HEX) {
-        if (hex_spelling(creature_ptr, HEX_DEMON_AURA)) {
-            creature_ptr->sh_fire = TRUE;
-        }
-    }
-
-    if (creature_ptr->special_defense & KAMAE_SEIRYU) {
-        creature_ptr->sh_fire = TRUE;
+    if (creature_ptr->special_defense & KAMAE_SEIRYU || creature_ptr->special_defense & KATA_MUSOU) {
+        result |= 0x01U << FLAG_CAUSE_BATTLE_FORM;
     }
 
-    if (creature_ptr->ult_res || (creature_ptr->special_defense & KATA_MUSOU)) {
-        creature_ptr->sh_fire = TRUE;
+    if (hex_spelling(creature_ptr, HEX_DEMON_AURA) || creature_ptr->ult_res || creature_ptr->tim_sh_fire) {
+        result |= 0x01U << FLAG_CAUSE_MAGIC_TIME_EFFECT;
     }
 
-    if (creature_ptr->tim_sh_fire) {
-        creature_ptr->sh_fire = TRUE;
-    }
-
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
-
-        object_flags(creature_ptr, o_ptr, flgs);
-        if (have_flag(flgs, TR_SH_FIRE))
-            creature_ptr->sh_fire = TRUE;
-    }
+    result |= check_equipment_flags(creature_ptr, TR_SH_FIRE);
+    return result;
 }
 
-void have_sh_elec(player_type *creature_ptr)
+BIT_FLAGS has_sh_elec(player_type *creature_ptr)
 {
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
-    creature_ptr->sh_elec = FALSE;
+    BIT_FLAGS result = 0L;
 
     if (creature_ptr->muta3 & MUT3_ELEC_TOUC)
-        creature_ptr->sh_elec = TRUE;
-
-    if (creature_ptr->realm1 == REALM_HEX) {
-        if (hex_spelling(creature_ptr, HEX_SHOCK_CLOAK)) {
-            creature_ptr->sh_elec = TRUE;
-        }
-    }
+        result |= 0x01U << FLAG_CAUSE_MUTATION;
 
-    if (creature_ptr->special_defense & KAMAE_SEIRYU) {
-        creature_ptr->sh_elec = TRUE;
+    if (hex_spelling(creature_ptr, HEX_SHOCK_CLOAK) || creature_ptr->ult_res) {
+        result |= 0x01U << FLAG_CAUSE_MAGIC_TIME_EFFECT;
     }
 
-    if (creature_ptr->ult_res || (creature_ptr->special_defense & KATA_MUSOU)) {
-        creature_ptr->sh_elec = TRUE;
+    if (creature_ptr->special_defense & KAMAE_SEIRYU || (creature_ptr->special_defense & KATA_MUSOU)) {
+        result |= 0x01U << FLAG_CAUSE_BATTLE_FORM;
     }
 
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
-
-        object_flags(creature_ptr, o_ptr, flgs);
-        if (have_flag(flgs, TR_SH_ELEC))
-            creature_ptr->sh_elec = TRUE;
-    }
+    result |= check_equipment_flags(creature_ptr, TR_SH_ELEC);
+    return result;
 }
 
-void have_sh_cold(player_type *creature_ptr)
+BIT_FLAGS has_sh_cold(player_type *creature_ptr)
 {
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
-    creature_ptr->sh_cold = FALSE;
-
-    if (creature_ptr->realm1 == REALM_HEX) {
-        if (hex_spelling(creature_ptr, HEX_ICE_ARMOR)) {
-            creature_ptr->sh_cold = TRUE;
-        }
-    }
-
-    if (creature_ptr->special_defense & KAMAE_SEIRYU) {
-        creature_ptr->sh_cold = TRUE;
-    }
+    BIT_FLAGS result = 0L;
 
-    if (creature_ptr->ult_res || (creature_ptr->special_defense & KATA_MUSOU)) {
-        creature_ptr->sh_cold = TRUE;
+    if (creature_ptr->special_defense & KAMAE_SEIRYU || creature_ptr->special_defense & KATA_MUSOU) {
+        result |= 0x01U << FLAG_CAUSE_BATTLE_FORM;
     }
 
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
-
-        object_flags(creature_ptr, o_ptr, flgs);
-        if (have_flag(flgs, TR_SH_COLD))
-            creature_ptr->sh_cold = TRUE;
+    if (creature_ptr->ult_res || hex_spelling(creature_ptr, HEX_ICE_ARMOR)) {
+        result |= 0x01U << FLAG_CAUSE_MAGIC_TIME_EFFECT;
     }
-}
 
-void have_easy_spell(player_type *creature_ptr)
-{
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
-    creature_ptr->easy_spell = FALSE;
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
-
-        object_flags(creature_ptr, o_ptr, flgs);
-        if (have_flag(flgs, TR_EASY_SPELL))
-            creature_ptr->easy_spell = TRUE;
-    }
+    result |= check_equipment_flags(creature_ptr, TR_SH_COLD);
+    return result;
 }
 
-void have_heavy_spell(player_type *creature_ptr)
-{
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
-    creature_ptr->heavy_spell = FALSE;
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
+BIT_FLAGS has_easy_spell(player_type *creature_ptr) { return check_equipment_flags(creature_ptr, TR_EASY_SPELL); }
 
-        object_flags(creature_ptr, o_ptr, flgs);
-        if (o_ptr->name2 == EGO_AMU_FOOL)
-            creature_ptr->heavy_spell = TRUE;
-    }
-}
+BIT_FLAGS has_heavy_spell(player_type *creature_ptr) { return check_equipment_flags(creature_ptr, TR_HEAVY_SPELL); }
 
-void have_hold_exp(player_type *creature_ptr)
+BIT_FLAGS has_hold_exp(player_type *creature_ptr)
 {
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
-
-    creature_ptr->hold_exp = FALSE;
+    BIT_FLAGS result = 0L;
 
     if (creature_ptr->pseikaku == PERSONALITY_MUNCHKIN) {
-        creature_ptr->hold_exp = TRUE;
+        result |= 0x01U << FLAG_CAUSE_PERSONALITY;
     }
 
     if (creature_ptr->mimic_form == MIMIC_DEMON || creature_ptr->mimic_form == MIMIC_DEMON_LORD || creature_ptr->mimic_form == MIMIC_VAMPIRE) {
-        creature_ptr->hold_exp = TRUE;
+        result |= 0x01U << FLAG_CAUSE_RACE;
     }
 
-    if (is_specific_player_race(creature_ptr, RACE_HOBBIT) || is_specific_player_race(creature_ptr, RACE_SKELETON) ||
-        is_specific_player_race(creature_ptr, RACE_ZOMBIE) || is_specific_player_race(creature_ptr, RACE_VAMPIRE) ||
-               is_specific_player_race(creature_ptr, RACE_SPECTRE) || is_specific_player_race(creature_ptr, RACE_BALROG) ||
-        is_specific_player_race(creature_ptr, RACE_ANDROID)) {
-        creature_ptr->hold_exp = TRUE;
+    if (is_specific_player_race(creature_ptr, RACE_HOBBIT) || is_specific_player_race(creature_ptr, RACE_SKELETON)
+        || is_specific_player_race(creature_ptr, RACE_ZOMBIE) || is_specific_player_race(creature_ptr, RACE_VAMPIRE)
+        || is_specific_player_race(creature_ptr, RACE_SPECTRE) || is_specific_player_race(creature_ptr, RACE_BALROG)
+        || is_specific_player_race(creature_ptr, RACE_ANDROID)) {
+        result |= 0x01U << FLAG_CAUSE_RACE;
     }
 
     if (is_specific_player_race(creature_ptr, RACE_GOLEM)) {
         if (creature_ptr->lev > 34)
-            creature_ptr->hold_exp = TRUE;
+            result |= 0x01U << FLAG_CAUSE_RACE;
     }
 
-    if (creature_ptr->ult_res || (creature_ptr->special_defense & KATA_MUSOU)) {
-        creature_ptr->hold_exp = TRUE;
+    if (creature_ptr->special_defense & KATA_MUSOU) {
+        result |= 0x01U << FLAG_CAUSE_BATTLE_FORM;
     }
 
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
-
-        object_flags(creature_ptr, o_ptr, flgs);
-        if (have_flag(flgs, TR_HOLD_EXP))
-            creature_ptr->hold_exp = TRUE;
+    if (creature_ptr->ult_res) {
+        result |= 0x01U << FLAG_CAUSE_MAGIC_TIME_EFFECT;
     }
+
+    result |= check_equipment_flags(creature_ptr, TR_HOLD_EXP);
+    return result;
 }
 
-void have_see_inv(player_type *creature_ptr)
+BIT_FLAGS has_see_inv(player_type *creature_ptr)
 {
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
-    creature_ptr->see_inv = FALSE;
+    BIT_FLAGS result = 0L;
 
-    if (creature_ptr->pclass == CLASS_NINJA || creature_ptr->lev > 29)
-        creature_ptr->see_inv = TRUE;
+    if (creature_ptr->pclass == CLASS_NINJA && creature_ptr->lev > 29)
+        result |= 0x01U << FLAG_CAUSE_CLASS;
 
     if (creature_ptr->mimic_form == MIMIC_DEMON || creature_ptr->mimic_form == MIMIC_DEMON_LORD || creature_ptr->mimic_form == MIMIC_VAMPIRE) {
-        creature_ptr->see_inv = TRUE;
-    }
-
-    if (!creature_ptr->mimic_form
-        && (creature_ptr->prace == RACE_HIGH_ELF || creature_ptr->prace == RACE_GOLEM || creature_ptr->prace == RACE_SKELETON
-            || creature_ptr->prace == RACE_ZOMBIE || creature_ptr->prace == RACE_SPECTRE || creature_ptr->prace == RACE_ARCHON)) {
-        creature_ptr->see_inv = TRUE;
-    }
-
-    if (!creature_ptr->mimic_form && creature_ptr->prace == RACE_DARK_ELF) {
-        if (creature_ptr->lev > 19)
-            creature_ptr->see_inv = TRUE;
-    }
-
-    if (!creature_ptr->mimic_form && creature_ptr->prace == RACE_MIND_FLAYER) {
-        if (creature_ptr->lev > 14)
-            creature_ptr->see_inv = TRUE;
-    }
-
-    if (!creature_ptr->mimic_form && (creature_ptr->prace == RACE_IMP || creature_ptr->prace == RACE_BALROG)) {
-        if (creature_ptr->lev > 9)
-            creature_ptr->see_inv = TRUE;
+        result |= 0x01U << FLAG_CAUSE_RACE;
+    } else if (is_specific_player_race(creature_ptr, RACE_HIGH_ELF) || is_specific_player_race(creature_ptr, RACE_GOLEM)
+        || is_specific_player_race(creature_ptr, RACE_SKELETON) || is_specific_player_race(creature_ptr, RACE_ZOMBIE)
+        || is_specific_player_race(creature_ptr, RACE_SPECTRE) || is_specific_player_race(creature_ptr, RACE_ARCHON)) {
+        result |= 0x01U << FLAG_CAUSE_RACE;
+    } else if (is_specific_player_race(creature_ptr, RACE_DARK_ELF) && creature_ptr->lev > 19) {
+        result |= 0x01U << FLAG_CAUSE_RACE;
+    } else if (is_specific_player_race(creature_ptr, RACE_MIND_FLAYER) && creature_ptr->lev > 14) {
+        result |= 0x01U << FLAG_CAUSE_RACE;
+    } else if ((is_specific_player_race(creature_ptr, RACE_IMP) || is_specific_player_race(creature_ptr, RACE_BALROG)) && creature_ptr->lev > 9) {
+        result |= 0x01U << FLAG_CAUSE_RACE;
     }
 
-    if (creature_ptr->ult_res || (creature_ptr->special_defense & KATA_MUSOU)) {
-        creature_ptr->see_inv = TRUE;
+    if (creature_ptr->special_defense & KATA_MUSOU) {
+        result |= 0x01U << FLAG_CAUSE_BATTLE_FORM;
     }
 
-    if (creature_ptr->tim_invis) {
-        creature_ptr->see_inv = TRUE;
+    if (creature_ptr->ult_res || creature_ptr->tim_invis) {
+        result |= 0x01U << FLAG_CAUSE_MAGIC_TIME_EFFECT;
     }
 
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
-
-        object_flags(creature_ptr, o_ptr, flgs);
-        if (have_flag(flgs, TR_SEE_INVIS))
-            creature_ptr->see_inv = TRUE;
-    }
+    result |= check_equipment_flags(creature_ptr, TR_SEE_INVIS);
+    return result;
 }
 
-void have_free_act(player_type *creature_ptr)
+BIT_FLAGS has_magic_mastery(player_type *creature_ptr) { return check_equipment_flags(creature_ptr, TR_MAGIC_MASTERY); }
+
+BIT_FLAGS has_free_act(player_type *creature_ptr)
 {
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
-    creature_ptr->free_act = FALSE;
+    BIT_FLAGS result = 0L;
 
     if (creature_ptr->muta3 & MUT3_MOTION)
-        creature_ptr->free_act = TRUE;
-
-    if (!creature_ptr->mimic_form && creature_ptr->prace == RACE_GNOME) {
-        creature_ptr->free_act = TRUE;
-    }
-
-    if (!creature_ptr->mimic_form && creature_ptr->prace == RACE_GOLEM) {
-        creature_ptr->free_act = TRUE;
-    }
+        result |= 0x01U << FLAG_CAUSE_MUTATION;
 
-    if (!creature_ptr->mimic_form && creature_ptr->prace == RACE_SPECTRE) {
-        creature_ptr->free_act = TRUE;
+    if (is_specific_player_race(creature_ptr, RACE_GNOME) || is_specific_player_race(creature_ptr, RACE_GOLEM)
+        || is_specific_player_race(creature_ptr, RACE_SPECTRE) || is_specific_player_race(creature_ptr, RACE_ANDROID)) {
+        result |= 0x01U << FLAG_CAUSE_RACE;
     }
 
-    if (!creature_ptr->mimic_form && creature_ptr->prace == RACE_ANDROID) {
-        creature_ptr->free_act = TRUE;
-    }
-
-    if (heavy_armor(creature_ptr) && (!creature_ptr->inventory_list[INVEN_RARM].k_idx || have_right_hand_weapon(creature_ptr))
-        && (!creature_ptr->inventory_list[INVEN_LARM].k_idx || have_left_hand_weapon(creature_ptr))) {
+    if (creature_ptr->pclass == CLASS_NINJA && !heavy_armor(creature_ptr)
+        && (!creature_ptr->inventory_list[INVEN_MAIN_HAND].k_idx || can_attack_with_main_hand(creature_ptr))
+        && (!creature_ptr->inventory_list[INVEN_SUB_HAND].k_idx || can_attack_with_sub_hand(creature_ptr))) {
         if (creature_ptr->lev > 24)
-            creature_ptr->free_act = TRUE;
+            result |= 0x01U << FLAG_CAUSE_CLASS;
     }
 
     if (creature_ptr->pclass == CLASS_MONK || creature_ptr->pclass == CLASS_FORCETRAINER) {
         if (!(heavy_armor(creature_ptr))) {
             if (creature_ptr->lev > 24)
-                creature_ptr->free_act = TRUE;
+                result |= 0x01U << FLAG_CAUSE_CLASS;
         }
     }
 
     if (creature_ptr->pclass == CLASS_BERSERKER) {
-        creature_ptr->free_act = TRUE;
+        result |= 0x01U << FLAG_CAUSE_CLASS;
     }
 
-    if (creature_ptr->ult_res || (creature_ptr->special_defense & KATA_MUSOU)) {
-        creature_ptr->free_act = TRUE;
+    if (creature_ptr->ult_res || creature_ptr->magicdef) {
+        result |= 0x01U << FLAG_CAUSE_MAGIC_TIME_EFFECT;
     }
 
-    if (creature_ptr->magicdef) {
-        creature_ptr->free_act = TRUE;
+    if (creature_ptr->special_defense & KATA_MUSOU) {
+        result |= 0x01U << FLAG_CAUSE_BATTLE_FORM;
     }
 
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
-
-        object_flags(creature_ptr, o_ptr, flgs);
-        if (have_flag(flgs, TR_FREE_ACT))
-            creature_ptr->free_act = TRUE;
-    }
+    result |= check_equipment_flags(creature_ptr, TR_FREE_ACT);
+    return result;
 }
 
-void have_sustain_str(player_type *creature_ptr)
+BIT_FLAGS has_sustain_str(player_type *creature_ptr)
 {
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
-    creature_ptr->sustain_str = FALSE;
+    BIT_FLAGS result = 0L;
+
     if (creature_ptr->pclass == CLASS_BERSERKER) {
-        creature_ptr->sustain_str = TRUE;
+        result |= 0x01U << FLAG_CAUSE_CLASS;
     }
-    if (!creature_ptr->mimic_form
-        && (creature_ptr->prace == RACE_HALF_TROLL || creature_ptr->prace == RACE_HALF_OGRE || creature_ptr->prace == RACE_HALF_GIANT)) {
-        creature_ptr->sustain_str = TRUE;
-    }
-    if (creature_ptr->ult_res || (creature_ptr->special_defense & KATA_MUSOU)) {
-        creature_ptr->sustain_str = TRUE;
+    if (is_specific_player_race(creature_ptr, RACE_HALF_TROLL) || is_specific_player_race(creature_ptr, RACE_HALF_OGRE)
+        || is_specific_player_race(creature_ptr, RACE_HALF_GIANT)) {
+        result |= 0x01U << FLAG_CAUSE_RACE;
     }
 
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
+    if (creature_ptr->ult_res) {
+        result |= 0x01U << FLAG_CAUSE_MAGIC_TIME_EFFECT;
+    }
 
-        object_flags(creature_ptr, o_ptr, flgs);
-        if (have_flag(flgs, TR_SUST_STR))
-            creature_ptr->sustain_str = TRUE;
+    if (creature_ptr->special_defense & KATA_MUSOU) {
+        result |= 0x01U << FLAG_CAUSE_BATTLE_FORM;
     }
+
+    result |= check_equipment_flags(creature_ptr, TR_SUST_STR);
+    return result;
 }
 
-void have_sustain_int(player_type *creature_ptr)
+BIT_FLAGS has_sustain_int(player_type *creature_ptr)
 {
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
-    creature_ptr->sustain_int = FALSE;
-    if (!creature_ptr->mimic_form && (creature_ptr->prace == RACE_MIND_FLAYER)) {
-        creature_ptr->sustain_int = TRUE;
-    }
+    BIT_FLAGS result = 0L;
 
-    if (creature_ptr->ult_res || (creature_ptr->special_defense & KATA_MUSOU)) {
-        creature_ptr->sustain_int = TRUE;
+    if (is_specific_player_race(creature_ptr, RACE_MIND_FLAYER)) {
+        result |= 0x01U << FLAG_CAUSE_RACE;
     }
 
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
+    if (creature_ptr->ult_res) {
+        result |= 0x01U << FLAG_CAUSE_MAGIC_TIME_EFFECT;
+    }
 
-        object_flags(creature_ptr, o_ptr, flgs);
-        if (have_flag(flgs, TR_SUST_INT))
-            creature_ptr->sustain_int = TRUE;
+    if (creature_ptr->special_defense & KATA_MUSOU) {
+        result |= 0x01U << FLAG_CAUSE_BATTLE_FORM;
     }
+
+    result |= check_equipment_flags(creature_ptr, TR_SUST_INT);
+    return result;
 }
 
-void have_sustain_wis(player_type *creature_ptr)
+BIT_FLAGS has_sustain_wis(player_type *creature_ptr)
 {
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
-    creature_ptr->sustain_wis = FALSE;
+    BIT_FLAGS result = 0L;
+
     if (creature_ptr->pclass == CLASS_MINDCRAFTER && creature_ptr->lev > 19)
-        creature_ptr->sustain_wis = TRUE;
+        result |= 0x01U << FLAG_CAUSE_CLASS;
 
     if (!creature_ptr->mimic_form && (creature_ptr->prace == RACE_MIND_FLAYER)) {
-        creature_ptr->sustain_wis = TRUE;
+        result |= 0x01U << FLAG_CAUSE_RACE;
     }
 
-    if (creature_ptr->ult_res || (creature_ptr->special_defense & KATA_MUSOU)) {
-        creature_ptr->sustain_wis = TRUE;
+    if (creature_ptr->ult_res) {
+        result |= 0x01U << FLAG_CAUSE_MAGIC_TIME_EFFECT;
     }
 
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
-
-        object_flags(creature_ptr, o_ptr, flgs);
-        if (have_flag(flgs, TR_SUST_WIS))
-            creature_ptr->sustain_wis = TRUE;
+    if (creature_ptr->special_defense & KATA_MUSOU) {
+        result |= 0x01U << FLAG_CAUSE_BATTLE_FORM;
     }
+
+    result |= check_equipment_flags(creature_ptr, TR_SUST_WIS);
+    return result;
 }
 
-void have_sustain_dex(player_type *creature_ptr)
+BIT_FLAGS has_sustain_dex(player_type *creature_ptr)
 {
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
-    creature_ptr->sustain_dex = FALSE;
+    BIT_FLAGS result = 0L;
     if (creature_ptr->pclass == CLASS_BERSERKER) {
-        creature_ptr->sustain_dex = TRUE;
+        result |= 0x01U << FLAG_CAUSE_CLASS;
     }
 
     if (creature_ptr->pclass == CLASS_NINJA && creature_ptr->lev > 24)
-        creature_ptr->sustain_dex = TRUE;
+        result |= 0x01U << FLAG_CAUSE_CLASS;
 
-    if (creature_ptr->ult_res || (creature_ptr->special_defense & KATA_MUSOU)) {
-        creature_ptr->sustain_dex = TRUE;
+    if (creature_ptr->ult_res) {
+        result |= 0x01U << FLAG_CAUSE_MAGIC_TIME_EFFECT;
     }
 
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
-
-        object_flags(creature_ptr, o_ptr, flgs);
-        if (have_flag(flgs, TR_SUST_DEX))
-            creature_ptr->sustain_dex = TRUE;
+    if (creature_ptr->special_defense & KATA_MUSOU) {
+        result |= 0x01U << FLAG_CAUSE_BATTLE_FORM;
     }
+
+    result |= check_equipment_flags(creature_ptr, TR_SUST_DEX);
+    return result;
 }
 
-void have_sustain_con(player_type *creature_ptr)
+BIT_FLAGS has_sustain_con(player_type *creature_ptr)
 {
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
-    creature_ptr->sustain_con = FALSE;
+    BIT_FLAGS result = 0L;
     if (creature_ptr->pclass == CLASS_BERSERKER) {
-        creature_ptr->sustain_con = TRUE;
+        result |= 0x01U << FLAG_CAUSE_CLASS;
     }
 
     if (!creature_ptr->mimic_form && (creature_ptr->prace == RACE_AMBERITE || creature_ptr->prace == RACE_DUNADAN)) {
-        creature_ptr->sustain_con = TRUE;
+        result |= 0x01U << FLAG_CAUSE_RACE;
     }
 
-    if (creature_ptr->ult_res || (creature_ptr->special_defense & KATA_MUSOU)) {
-        creature_ptr->sustain_con = TRUE;
+    if (creature_ptr->ult_res) {
+        result |= 0x01U << FLAG_CAUSE_MAGIC_TIME_EFFECT;
     }
 
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
-
-        object_flags(creature_ptr, o_ptr, flgs);
-        if (have_flag(flgs, TR_SUST_CON))
-            creature_ptr->sustain_con = TRUE;
+    if (creature_ptr->special_defense & KATA_MUSOU) {
+        result |= 0x01U << FLAG_CAUSE_BATTLE_FORM;
     }
+
+    result |= check_equipment_flags(creature_ptr, TR_SUST_CON);
+    return result;
 }
 
-void have_sustain_chr(player_type *creature_ptr)
+BIT_FLAGS has_sustain_chr(player_type *creature_ptr)
 {
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
-    creature_ptr->sustain_chr = FALSE;
+    BIT_FLAGS result = 0L;
 
-    if (creature_ptr->ult_res || (creature_ptr->special_defense & KATA_MUSOU)) {
-        creature_ptr->sustain_chr = TRUE;
+    if (creature_ptr->ult_res) {
+        result |= 0x01U << FLAG_CAUSE_MAGIC_TIME_EFFECT;
     }
 
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
-
-        object_flags(creature_ptr, o_ptr, flgs);
-        if (have_flag(flgs, TR_SUST_CHR))
-            creature_ptr->sustain_chr = TRUE;
+    if (creature_ptr->special_defense & KATA_MUSOU) {
+        result |= 0x01U << FLAG_CAUSE_BATTLE_FORM;
     }
+
+    result |= check_equipment_flags(creature_ptr, TR_SUST_CHR);
+    return result;
 }
 
-void have_levitation(player_type *creature_ptr)
+BIT_FLAGS has_levitation(player_type *creature_ptr)
 {
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
-    creature_ptr->levitation = FALSE;
+    BIT_FLAGS result = 0L;
 
-    if (creature_ptr->mimic_form == MIMIC_DEMON_LORD) {
-        creature_ptr->levitation = TRUE;
+    if (creature_ptr->muta3 & MUT3_WINGS) {
+        result |= 0x01U << FLAG_CAUSE_MUTATION;
     }
 
-    if (creature_ptr->muta3 & MUT3_WINGS)
-        creature_ptr->levitation = TRUE;
-
-    if (!creature_ptr->mimic_form
-        && (creature_ptr->prace == RACE_DRACONIAN || creature_ptr->prace == RACE_SPECTRE || creature_ptr->prace == RACE_SPRITE
-            || creature_ptr->prace == RACE_ARCHON || creature_ptr->prace == RACE_S_FAIRY)) {
-        creature_ptr->levitation = TRUE;
+    if (creature_ptr->mimic_form == MIMIC_DEMON_LORD) {
+        result |= 0x01U << FLAG_CAUSE_RACE;
     }
 
-    if (creature_ptr->special_defense & KAMAE_SEIRYU || creature_ptr->special_defense & KAMAE_SUZAKU) {
-        creature_ptr->levitation = TRUE;
+    if (is_specific_player_race(creature_ptr, RACE_DRACONIAN) || is_specific_player_race(creature_ptr, RACE_SPECTRE)
+        || is_specific_player_race(creature_ptr, RACE_SPRITE) || is_specific_player_race(creature_ptr, RACE_ARCHON)
+        || is_specific_player_race(creature_ptr, RACE_S_FAIRY)) {
+        result |= 0x01U << FLAG_CAUSE_RACE;
     }
 
-    if (creature_ptr->ult_res || (creature_ptr->special_defense & KATA_MUSOU)) {
-        creature_ptr->levitation = TRUE;
+    if (creature_ptr->special_defense & KAMAE_SEIRYU || creature_ptr->special_defense & KAMAE_SUZAKU || (creature_ptr->special_defense & KATA_MUSOU)) {
+        result |= 0x01U << FLAG_CAUSE_BATTLE_FORM;
     }
 
-    if (creature_ptr->magicdef) {
+    if (creature_ptr->ult_res || creature_ptr->magicdef) {
+        result |= 0x01U << FLAG_CAUSE_MAGIC_TIME_EFFECT;
     }
 
     if (creature_ptr->riding) {
         monster_type *riding_m_ptr = &creature_ptr->current_floor_ptr->m_list[creature_ptr->riding];
         monster_race *riding_r_ptr = &r_info[riding_m_ptr->r_idx];
-        creature_ptr->levitation = (riding_r_ptr->flags7 & RF7_CAN_FLY) ? TRUE : FALSE;
+        result = (riding_r_ptr->flags7 & RF7_CAN_FLY) ? result : 0;
     }
 
     if (creature_ptr->tim_levitation) {
-        creature_ptr->levitation = TRUE;
+        result |= 0x01U << FLAG_CAUSE_MAGIC_TIME_EFFECT;
     }
 
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
-        object_flags(creature_ptr, o_ptr, flgs);
-        if (have_flag(flgs, TR_LEVITATION))
-            creature_ptr->levitation = TRUE;
-    }
+    result |= check_equipment_flags(creature_ptr, TR_LEVITATION);
+    return result;
 }
 
-void have_can_swim(player_type *creature_ptr)
+void has_can_swim(player_type *creature_ptr)
 {
     creature_ptr->can_swim = FALSE;
     if (creature_ptr->riding) {
@@ -1144,19 +734,17 @@ void have_can_swim(player_type *creature_ptr)
     }
 }
 
-void have_slow_digest(player_type *creature_ptr)
+BIT_FLAGS has_slow_digest(player_type *creature_ptr)
 {
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
-    creature_ptr->slow_digest = FALSE;
+    BIT_FLAGS result = 0L;
 
     if (creature_ptr->pclass == CLASS_NINJA) {
-        creature_ptr->slow_digest = TRUE;
+        result |= 0x01U << FLAG_CAUSE_CLASS;
     }
 
     if (creature_ptr->lev > 14 && !creature_ptr->mimic_form && creature_ptr->prace == RACE_HALF_TROLL) {
         if (creature_ptr->pclass == CLASS_WARRIOR || creature_ptr->pclass == CLASS_BERSERKER) {
-            creature_ptr->slow_digest = TRUE;
+            result |= 0x01U << FLAG_CAUSE_CLASS;
             /* Let's not make Regeneration
              * a disadvantage for the poor warriors who can
              * never learn a spell that satisfies hunger (actually
@@ -1165,86 +753,64 @@ void have_slow_digest(player_type *creature_ptr)
         }
     }
 
-    if (creature_ptr->ult_res || (creature_ptr->special_defense & KATA_MUSOU)) {
-        creature_ptr->slow_digest = TRUE;
+    if (creature_ptr->special_defense & KATA_MUSOU) {
+        result |= 0x01U << FLAG_CAUSE_BATTLE_FORM;
+    }
+
+    if (creature_ptr->ult_res) {
+        result |= 0x01U << FLAG_CAUSE_MAGIC_TIME_EFFECT;
     }
 
     if (!creature_ptr->mimic_form
         && (creature_ptr->prace == RACE_GOLEM || creature_ptr->prace == RACE_ZOMBIE || creature_ptr->prace == RACE_SPECTRE
             || creature_ptr->prace == RACE_ANDROID)) {
-        creature_ptr->slow_digest = TRUE;
+        result |= 0x01U << FLAG_CAUSE_RACE;
     }
 
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
-        object_flags(creature_ptr, o_ptr, flgs);
-        if (have_flag(flgs, TR_SLOW_DIGEST))
-            creature_ptr->slow_digest = TRUE;
-    }
+    result |= check_equipment_flags(creature_ptr, TR_SLOW_DIGEST);
+    return result;
 }
 
-void have_regenerate(player_type *creature_ptr)
+BIT_FLAGS has_regenerate(player_type *creature_ptr)
 {
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
-    creature_ptr->regenerate = FALSE;
+    BIT_FLAGS result = 0L;
 
-    if (!creature_ptr->mimic_form) {
-        switch (creature_ptr->prace) {
-        case RACE_HALF_TROLL:
-            if (creature_ptr->lev > 14) {
-                creature_ptr->regenerate = TRUE;
-            }
-            break;
-        case RACE_AMBERITE:
-            creature_ptr->regenerate = TRUE;
-            break;
-        }
+    if (is_specific_player_race(creature_ptr, RACE_HALF_TROLL) && creature_ptr->lev > 14) {
+        result |= 0x01U << FLAG_CAUSE_RACE;
     }
 
-    switch (creature_ptr->pclass) {
-    case CLASS_WARRIOR:
-        if (creature_ptr->lev > 44)
-            creature_ptr->regenerate = TRUE;
-        break;
-    case CLASS_BERSERKER:
-        creature_ptr->regenerate = TRUE;
-        break;
+    if (is_specific_player_race(creature_ptr, RACE_AMBERITE)) {
+        result |= 0x01U << FLAG_CAUSE_RACE;
     }
 
-    if (creature_ptr->muta3 & MUT3_FLESH_ROT)
-        creature_ptr->regenerate = FALSE;
+    if (creature_ptr->pclass == CLASS_WARRIOR && creature_ptr->lev > 44) {
+        result |= 0x01U << FLAG_CAUSE_RACE;
+    }
+
+    if (creature_ptr->pclass == CLASS_BERSERKER) {
+        result |= 0x01U << FLAG_CAUSE_RACE;
+    }
 
     if (creature_ptr->muta3 & MUT3_REGEN)
-        creature_ptr->regenerate = TRUE;
+        result |= 0x01U << FLAG_CAUSE_MUTATION;
 
-    if (creature_ptr->ult_res || (creature_ptr->special_defense & KATA_MUSOU)) {
-        creature_ptr->regenerate = TRUE;
+    if (creature_ptr->special_defense & KATA_MUSOU) {
+        result |= 0x01U << FLAG_CAUSE_MUTATION;
     }
 
-    if (creature_ptr->realm1 == REALM_HEX) {
-        if (hex_spelling(creature_ptr, HEX_DEMON_AURA)) {
-            creature_ptr->regenerate = TRUE;
-        }
+    if (hex_spelling(creature_ptr, HEX_DEMON_AURA) || creature_ptr->ult_res || creature_ptr->tim_regen) {
+        result |= 0x01U << FLAG_CAUSE_MAGIC_TIME_EFFECT;
     }
 
-    if (creature_ptr->tim_regen) {
-        creature_ptr->regenerate = TRUE;
-    }
+    result |= check_equipment_flags(creature_ptr, TR_REGEN);
 
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
-        object_flags(creature_ptr, o_ptr, flgs);
-        if (have_flag(flgs, TR_REGEN))
-            creature_ptr->regenerate = TRUE;
-    }
+    if (creature_ptr->muta3 & MUT3_FLESH_ROT)
+        result = 0L;
+
+    return result;
 }
 
-void have_curses(player_type *creature_ptr)
+void has_curses(player_type *creature_ptr)
 {
     object_type *o_ptr;
     BIT_FLAGS flgs[TR_FLAG_SIZE];
@@ -1253,51 +819,51 @@ void have_curses(player_type *creature_ptr)
     if (creature_ptr->pseikaku == PERSONALITY_SEXY)
         creature_ptr->cursed |= (TRC_AGGRAVATE);
 
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
+    for (inventory_slot_type i = INVEN_MAIN_HAND; i < INVEN_TOTAL; i++) {
         o_ptr = &creature_ptr->inventory_list[i];
         if (!o_ptr->k_idx)
             continue;
         object_flags(creature_ptr, o_ptr, flgs);
-        if (have_flag(flgs, TR_AGGRAVATE))
+        if (has_flag(flgs, TR_AGGRAVATE))
             creature_ptr->cursed |= TRC_AGGRAVATE;
-        if (have_flag(flgs, TR_DRAIN_EXP))
+        if (has_flag(flgs, TR_DRAIN_EXP))
             creature_ptr->cursed |= TRC_DRAIN_EXP;
-        if (have_flag(flgs, TR_TY_CURSE))
+        if (has_flag(flgs, TR_TY_CURSE))
             creature_ptr->cursed |= TRC_TY_CURSE;
-        if (have_flag(flgs, TR_ADD_L_CURSE))
+        if (has_flag(flgs, TR_ADD_L_CURSE))
             creature_ptr->cursed |= TRC_ADD_L_CURSE;
-        if (have_flag(flgs, TR_ADD_H_CURSE))
+        if (has_flag(flgs, TR_ADD_H_CURSE))
             creature_ptr->cursed |= TRC_ADD_H_CURSE;
-        if (have_flag(flgs, TR_DRAIN_HP))
+        if (has_flag(flgs, TR_DRAIN_HP))
             creature_ptr->cursed |= TRC_DRAIN_HP;
-        if (have_flag(flgs, TR_DRAIN_MANA))
+        if (has_flag(flgs, TR_DRAIN_MANA))
             creature_ptr->cursed |= TRC_DRAIN_MANA;
-        if (have_flag(flgs, TR_CALL_ANIMAL))
+        if (has_flag(flgs, TR_CALL_ANIMAL))
             creature_ptr->cursed |= TRC_CALL_ANIMAL;
-        if (have_flag(flgs, TR_CALL_DEMON))
+        if (has_flag(flgs, TR_CALL_DEMON))
             creature_ptr->cursed |= TRC_CALL_DEMON;
-        if (have_flag(flgs, TR_CALL_DRAGON))
+        if (has_flag(flgs, TR_CALL_DRAGON))
             creature_ptr->cursed |= TRC_CALL_DRAGON;
-        if (have_flag(flgs, TR_CALL_UNDEAD))
+        if (has_flag(flgs, TR_CALL_UNDEAD))
             creature_ptr->cursed |= TRC_CALL_UNDEAD;
-        if (have_flag(flgs, TR_COWARDICE))
+        if (has_flag(flgs, TR_COWARDICE))
             creature_ptr->cursed |= TRC_COWARDICE;
-        if (have_flag(flgs, TR_LOW_MELEE))
+        if (has_flag(flgs, TR_LOW_MELEE))
             creature_ptr->cursed |= TRC_LOW_MELEE;
-        if (have_flag(flgs, TR_LOW_AC))
+        if (has_flag(flgs, TR_LOW_AC))
             creature_ptr->cursed |= TRC_LOW_AC;
-        if (have_flag(flgs, TR_LOW_MAGIC))
+        if (has_flag(flgs, TR_LOW_MAGIC))
             creature_ptr->cursed |= TRC_LOW_MAGIC;
-        if (have_flag(flgs, TR_FAST_DIGEST))
+        if (has_flag(flgs, TR_FAST_DIGEST))
             creature_ptr->cursed |= TRC_FAST_DIGEST;
-        if (have_flag(flgs, TR_SLOW_REGEN))
+        if (has_flag(flgs, TR_SLOW_REGEN))
             creature_ptr->cursed |= TRC_SLOW_REGEN;
 
         creature_ptr->cursed |= (o_ptr->curse_flags & (0xFFFFFFF0L));
         if (o_ptr->name1 == ART_CHAINSWORD)
             creature_ptr->cursed |= TRC_CHAINSWORD;
 
-        if (have_flag(flgs, TR_TELEPORT)) {
+        if (has_flag(flgs, TR_TELEPORT)) {
             if (object_is_cursed(o_ptr))
                 creature_ptr->cursed |= TRC_TELEPORT;
             else {
@@ -1314,48 +880,26 @@ void have_curses(player_type *creature_ptr)
 
     if (creature_ptr->cursed & TRC_TELEPORT)
         creature_ptr->cursed &= ~(TRC_TELEPORT_SELF);
-
-    if ((is_specific_player_race(creature_ptr, RACE_S_FAIRY)) && (creature_ptr->pseikaku != PERSONALITY_SEXY) && (creature_ptr->cursed & TRC_AGGRAVATE)) {
-        creature_ptr->cursed &= ~(TRC_AGGRAVATE);
-    }
 }
 
-void have_impact(player_type *creature_ptr)
-{
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
-    creature_ptr->impact[0] = FALSE;
-    creature_ptr->impact[1] = FALSE;
-
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
-        object_flags(creature_ptr, o_ptr, flgs);
-        if (have_flag(flgs, TR_IMPACT))
-            creature_ptr->impact[(i == INVEN_RARM) ? 0 : 1] = TRUE;
-    }
-}
+BIT_FLAGS has_impact(player_type *creature_ptr) { return check_equipment_flags(creature_ptr, TR_IMPACT); }
 
-void have_extra_blow(player_type *creature_ptr)
+void has_extra_blow(player_type *creature_ptr)
 {
     object_type *o_ptr;
     BIT_FLAGS flgs[TR_FLAG_SIZE];
     creature_ptr->extra_blows[0] = creature_ptr->extra_blows[1] = 0;
 
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
+    for (inventory_slot_type i = INVEN_MAIN_HAND; i < INVEN_TOTAL; i++) {
         o_ptr = &creature_ptr->inventory_list[i];
         if (!o_ptr->k_idx)
             continue;
 
         object_flags(creature_ptr, o_ptr, flgs);
-
-        if (have_flag(flgs, TR_INFRA))
-            creature_ptr->see_infra += o_ptr->pval;
-        if (have_flag(flgs, TR_BLOWS)) {
-            if ((i == INVEN_RARM || i == INVEN_RIGHT) && !have_two_handed_weapons(creature_ptr))
+        if (has_flag(flgs, TR_BLOWS)) {
+            if ((i == INVEN_MAIN_HAND || i == INVEN_MAIN_RING) && !has_two_handed_weapons(creature_ptr))
                 creature_ptr->extra_blows[0] += o_ptr->pval;
-            else if ((i == INVEN_LARM || i == INVEN_LEFT) && !have_two_handed_weapons(creature_ptr))
+            else if ((i == INVEN_SUB_HAND || i == INVEN_SUB_RING) && !has_two_handed_weapons(creature_ptr))
                 creature_ptr->extra_blows[1] += o_ptr->pval;
             else {
                 creature_ptr->extra_blows[0] += o_ptr->pval;
@@ -1365,822 +909,793 @@ void have_extra_blow(player_type *creature_ptr)
     }
 }
 
-void have_resist_acid(player_type *creature_ptr)
+BIT_FLAGS has_resist_acid(player_type *creature_ptr)
 {
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
-    creature_ptr->resist_acid = FALSE;
+    BIT_FLAGS result = 0L;
 
     if (creature_ptr->mimic_form == MIMIC_DEMON_LORD) {
-        creature_ptr->resist_acid = TRUE;
-    }
-
-    if (!creature_ptr->mimic_form && (creature_ptr->prace == RACE_YEEK || creature_ptr->prace == RACE_KLACKON)) {
-        creature_ptr->resist_acid = TRUE;
+        result |= 0x01U << FLAG_CAUSE_RACE;
+    } else if (is_specific_player_race(creature_ptr, RACE_YEEK) || is_specific_player_race(creature_ptr, RACE_KLACKON)) {
+        result |= 0x01U << FLAG_CAUSE_RACE;
+    } else if (is_specific_player_race(creature_ptr, RACE_DRACONIAN) && creature_ptr->lev > 14) {
+        result |= 0x01U << FLAG_CAUSE_RACE;
     }
 
-    if (!creature_ptr->mimic_form && creature_ptr->prace == RACE_DRACONIAN && creature_ptr->lev > 14) {
-        creature_ptr->resist_acid = TRUE;
+    if (creature_ptr->special_defense & KAMAE_SEIRYU || creature_ptr->special_defense & KATA_MUSOU) {
+        result |= 0x01U << FLAG_CAUSE_BATTLE_FORM;
     }
 
-    if (creature_ptr->special_defense & KAMAE_SEIRYU) {
-        creature_ptr->resist_acid = TRUE;
+    if (creature_ptr->ult_res) {
+        result |= 0x01U << FLAG_CAUSE_MAGIC_TIME_EFFECT;
     }
 
-    if (creature_ptr->ult_res || (creature_ptr->special_defense & KATA_MUSOU)) {
-        creature_ptr->resist_acid = TRUE;
-    }
+    result |= has_immune_acid(creature_ptr);
 
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
+    result |= check_equipment_flags(creature_ptr, TR_RES_ACID);
+    return result;
+}
 
-        object_flags(creature_ptr, o_ptr, flgs);
-        if (have_flag(flgs, TR_RES_ACID))
-            creature_ptr->resist_acid = TRUE;
+BIT_FLAGS has_vuln_acid(player_type *creature_ptr)
+{
+    BIT_FLAGS result = 0L;
+    if (creature_ptr->muta3 & MUT3_VULN_ELEM) {
+        result |= 0x01U << FLAG_CAUSE_MUTATION;
     }
 
-    if (creature_ptr->immune_acid)
-        creature_ptr->resist_acid = TRUE;
+    if (creature_ptr->special_defense & KATA_KOUKIJIN) {
+        result |= 0x01U << FLAG_CAUSE_BATTLE_FORM;
+    }
+    return result;
 }
 
-void have_resist_elec(player_type *creature_ptr)
+BIT_FLAGS has_resist_elec(player_type *creature_ptr)
 {
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
-    creature_ptr->resist_elec = FALSE;
+    BIT_FLAGS result = 0L;
 
     if (creature_ptr->mimic_form == MIMIC_DEMON_LORD) {
-        creature_ptr->resist_elec = TRUE;
+        result |= 0x01U << FLAG_CAUSE_RACE;
+    } else if (is_specific_player_race(creature_ptr, RACE_DRACONIAN) && creature_ptr->lev > 19) {
+        result |= 0x01U << FLAG_CAUSE_RACE;
     }
 
-    if (!creature_ptr->mimic_form && creature_ptr->prace == RACE_DRACONIAN && creature_ptr->lev > 19) {
-        creature_ptr->resist_elec = TRUE;
+    if (creature_ptr->special_defense & KAMAE_SEIRYU || creature_ptr->special_defense & KATA_MUSOU) {
+        result |= 0x01U << FLAG_CAUSE_BATTLE_FORM;
     }
 
-    if (creature_ptr->special_defense & KAMAE_SEIRYU) {
-        creature_ptr->resist_elec = TRUE;
+    if (creature_ptr->ult_res) {
+        result |= 0x01U << FLAG_CAUSE_MAGIC_TIME_EFFECT;
     }
 
-    if (creature_ptr->ult_res || (creature_ptr->special_defense & KATA_MUSOU)) {
-        creature_ptr->resist_elec = TRUE;
-    }
+    result |= check_equipment_flags(creature_ptr, TR_RES_ELEC);
+    result |= has_immune_elec(creature_ptr);
+    return result;
+}
 
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
+BIT_FLAGS has_vuln_elec(player_type *creature_ptr)
+{
+    BIT_FLAGS result = 0L;
+    if (creature_ptr->muta3 & MUT3_VULN_ELEM) {
+        result |= 0x01U << FLAG_CAUSE_MUTATION;
+    }
 
-        object_flags(creature_ptr, o_ptr, flgs);
-        if (have_flag(flgs, TR_RES_ELEC))
-            creature_ptr->resist_elec = TRUE;
+    if (is_specific_player_race(creature_ptr, RACE_ANDROID)) {
+        result |= 0x01U << FLAG_CAUSE_RACE;
     }
 
-    if (creature_ptr->immune_elec)
-        creature_ptr->resist_elec = TRUE;
+    if (creature_ptr->special_defense & KATA_KOUKIJIN) {
+        result |= 0x01U << FLAG_CAUSE_BATTLE_FORM;
+    }
+    return result;
 }
 
-void have_resist_fire(player_type *creature_ptr)
+BIT_FLAGS has_resist_fire(player_type *creature_ptr)
 {
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
-    creature_ptr->resist_fire = FALSE;
+    BIT_FLAGS result = 0L;
 
     if (creature_ptr->mimic_form == MIMIC_DEMON || creature_ptr->mimic_form == MIMIC_DEMON_LORD) {
-        creature_ptr->resist_fire = TRUE;
+        result |= 0x01U << FLAG_CAUSE_RACE;
     }
 
-    if (!creature_ptr->mimic_form && creature_ptr->prace == RACE_DRACONIAN && creature_ptr->lev > 4) {
-        creature_ptr->resist_fire = TRUE;
+    if (is_specific_player_race(creature_ptr, RACE_DRACONIAN) && creature_ptr->lev > 4) {
+        result |= 0x01U << FLAG_CAUSE_RACE;
     }
 
     if (!creature_ptr->mimic_form && (creature_ptr->prace == RACE_IMP || creature_ptr->prace == RACE_BALROG)) {
-        creature_ptr->resist_fire = TRUE;
+        result |= 0x01U << FLAG_CAUSE_RACE;
     }
 
-    if (creature_ptr->special_defense & KAMAE_SEIRYU) {
-        creature_ptr->resist_fire = TRUE;
+    if (creature_ptr->special_defense & KAMAE_SEIRYU || creature_ptr->special_defense & KATA_MUSOU) {
+        result |= 0x01U << FLAG_CAUSE_BATTLE_FORM;
     }
 
-    if (creature_ptr->ult_res || (creature_ptr->special_defense & KATA_MUSOU)) {
-        creature_ptr->resist_fire = TRUE;
+    if (creature_ptr->ult_res) {
+        result |= 0x01U << FLAG_CAUSE_MAGIC_TIME_EFFECT;
     }
 
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
+    result |= check_equipment_flags(creature_ptr, TR_RES_FIRE);
+    result |= has_immune_fire(creature_ptr);
+    return result;
+}
 
-        object_flags(creature_ptr, o_ptr, flgs);
+BIT_FLAGS has_vuln_fire(player_type *creature_ptr)
+{
+    BIT_FLAGS result = 0L;
+    if (creature_ptr->muta3 & MUT3_VULN_ELEM) {
+        result |= 0x01U << FLAG_CAUSE_MUTATION;
+    }
 
-        if (have_flag(flgs, TR_RES_FIRE))
-            creature_ptr->resist_fire = TRUE;
+    if (is_specific_player_race(creature_ptr, RACE_ENT)) {
+        result |= 0x01U << FLAG_CAUSE_RACE;
     }
 
-    if (creature_ptr->immune_fire)
-        creature_ptr->resist_fire = TRUE;
+    if (creature_ptr->special_defense & KATA_KOUKIJIN) {
+        result |= 0x01U << FLAG_CAUSE_BATTLE_FORM;
+    }
+    return result;
 }
 
-void have_resist_cold(player_type *creature_ptr)
+BIT_FLAGS has_resist_cold(player_type *creature_ptr)
 {
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
-    creature_ptr->resist_cold = FALSE;
+    BIT_FLAGS result = 0L;
 
     if (creature_ptr->mimic_form == MIMIC_DEMON_LORD || creature_ptr->mimic_form == MIMIC_VAMPIRE) {
-        creature_ptr->resist_cold = TRUE;
+        result |= 0x01U << FLAG_CAUSE_RACE;
     }
 
     if (!creature_ptr->mimic_form && (creature_ptr->prace == RACE_ZOMBIE) && creature_ptr->lev > 4) {
-        creature_ptr->resist_cold = TRUE;
+        result |= 0x01U << FLAG_CAUSE_RACE;
     }
 
-    if (!creature_ptr->mimic_form && (creature_ptr->prace == RACE_DRACONIAN || creature_ptr->prace == RACE_SKELETON) && creature_ptr->lev > 9) {
-        creature_ptr->resist_cold = TRUE;
+    if ((is_specific_player_race(creature_ptr, RACE_DRACONIAN) || is_specific_player_race(creature_ptr, RACE_SKELETON)) && creature_ptr->lev > 9) {
+        result |= 0x01U << FLAG_CAUSE_RACE;
     }
 
     if (!creature_ptr->mimic_form && (creature_ptr->prace == RACE_VAMPIRE || creature_ptr->prace == RACE_SPECTRE)) {
-        creature_ptr->resist_fire = TRUE;
+        result |= 0x01U << FLAG_CAUSE_RACE;
     }
 
-    if (creature_ptr->special_defense & KAMAE_SEIRYU) {
-        creature_ptr->resist_cold = TRUE;
+    if (creature_ptr->special_defense & KAMAE_SEIRYU || creature_ptr->special_defense & KATA_MUSOU) {
+        result |= 0x01U << FLAG_CAUSE_BATTLE_FORM;
     }
 
-    if (creature_ptr->ult_res || (creature_ptr->special_defense & KATA_MUSOU)) {
-        creature_ptr->resist_cold = TRUE;
+    if (creature_ptr->ult_res) {
+        result |= 0x01U << FLAG_CAUSE_MAGIC_TIME_EFFECT;
     }
 
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
-
-        object_flags(creature_ptr, o_ptr, flgs);
+    result |= check_equipment_flags(creature_ptr, TR_RES_COLD);
+    result |= has_immune_cold(creature_ptr);
+    return result;
+}
 
-        if (have_flag(flgs, TR_RES_COLD))
-            creature_ptr->resist_cold = TRUE;
+BIT_FLAGS has_vuln_cold(player_type *creature_ptr)
+{
+    BIT_FLAGS result = 0L;
+    if (creature_ptr->muta3 & MUT3_VULN_ELEM) {
+        result |= 0x01U << FLAG_CAUSE_MUTATION;
     }
 
-    if (creature_ptr->immune_cold)
-        creature_ptr->resist_cold = TRUE;
+    if (creature_ptr->special_defense & KATA_KOUKIJIN) {
+        result |= 0x01U << FLAG_CAUSE_BATTLE_FORM;
+    }
+    return result;
 }
 
-void have_resist_pois(player_type *creature_ptr)
+BIT_FLAGS has_resist_pois(player_type *creature_ptr)
 {
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
-    creature_ptr->resist_pois = FALSE;
+    BIT_FLAGS result = 0L;
 
     if (creature_ptr->pclass == CLASS_NINJA && creature_ptr->lev > 19)
-        creature_ptr->resist_pois = TRUE;
+        result |= 0x01U << FLAG_CAUSE_CLASS;
 
     if (creature_ptr->mimic_form == MIMIC_VAMPIRE || creature_ptr->mimic_form == MIMIC_DEMON_LORD) {
-        creature_ptr->resist_pois = TRUE;
+        result |= 0x01U << FLAG_CAUSE_RACE;
     }
 
-    if (!creature_ptr->mimic_form && creature_ptr->prace == RACE_DRACONIAN && creature_ptr->lev > 34) {
-        creature_ptr->resist_pois = TRUE;
+    if (is_specific_player_race(creature_ptr, RACE_DRACONIAN) && creature_ptr->lev > 34) {
+        result |= 0x01U << FLAG_CAUSE_RACE;
     }
 
     if (!creature_ptr->mimic_form
         && (creature_ptr->prace == RACE_KOBOLD || creature_ptr->prace == RACE_GOLEM || creature_ptr->prace == RACE_SKELETON
             || creature_ptr->prace == RACE_VAMPIRE || creature_ptr->prace == RACE_SPECTRE || creature_ptr->prace == RACE_ANDROID)) {
-        creature_ptr->resist_pois = TRUE;
+        result |= 0x01U << FLAG_CAUSE_RACE;
     }
 
-    if (creature_ptr->special_defense & KAMAE_SEIRYU) {
-        creature_ptr->resist_pois = TRUE;
+    if (creature_ptr->special_defense & KAMAE_SEIRYU || creature_ptr->special_defense & KATA_MUSOU) {
+        result |= 0x01U << FLAG_CAUSE_BATTLE_FORM;
     }
 
-    if (creature_ptr->ult_res || (creature_ptr->special_defense & KATA_MUSOU)) {
-        creature_ptr->resist_pois = TRUE;
+    if (creature_ptr->ult_res) {
+        result |= 0x01U << FLAG_CAUSE_MAGIC_TIME_EFFECT;
     }
 
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
-
-        object_flags(creature_ptr, o_ptr, flgs);
-
-        if (have_flag(flgs, TR_RES_POIS))
-            creature_ptr->resist_pois = TRUE;
-    }
+    result |= check_equipment_flags(creature_ptr, TR_RES_POIS);
+    return result;
 }
 
-void have_resist_conf(player_type *creature_ptr)
+BIT_FLAGS has_resist_conf(player_type *creature_ptr)
 {
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
-    creature_ptr->resist_conf = FALSE;
+    BIT_FLAGS result = 0L;
 
     if (creature_ptr->pclass == CLASS_MINDCRAFTER && creature_ptr->lev > 29)
-        creature_ptr->resist_conf = TRUE;
+        result |= 0x01U << FLAG_CAUSE_CLASS;
 
     if (creature_ptr->pseikaku == PERSONALITY_CHARGEMAN || creature_ptr->pseikaku == PERSONALITY_MUNCHKIN) {
-        creature_ptr->resist_conf = TRUE;
+        result |= 0x01U << FLAG_CAUSE_PERSONALITY;
     }
 
     if (!creature_ptr->mimic_form && (creature_ptr->prace == RACE_KLACKON || creature_ptr->prace == RACE_BEASTMAN || creature_ptr->prace == RACE_KUTAR)) {
-        creature_ptr->resist_conf = TRUE;
+        result |= 0x01U << FLAG_CAUSE_RACE;
     }
 
     if (creature_ptr->mimic_form == MIMIC_DEMON_LORD) {
-        creature_ptr->resist_conf = TRUE;
+        result |= 0x01U << FLAG_CAUSE_RACE;
     }
 
-    if (creature_ptr->ult_res || (creature_ptr->special_defense & KATA_MUSOU)) {
-        creature_ptr->resist_conf = TRUE;
+    if (creature_ptr->ult_res || creature_ptr->magicdef) {
+        result |= 0x01U << FLAG_CAUSE_MAGIC_TIME_EFFECT;
     }
 
-    if (creature_ptr->magicdef) {
-        creature_ptr->resist_conf = TRUE;
+    if (creature_ptr->special_defense & KATA_MUSOU) {
+        result |= 0x01U << FLAG_CAUSE_BATTLE_FORM;
     }
 
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
-
-        object_flags(creature_ptr, o_ptr, flgs);
-
-        if (have_flag(flgs, TR_RES_CONF))
-            creature_ptr->resist_conf = TRUE;
-    }
+    result |= check_equipment_flags(creature_ptr, TR_RES_CONF);
+    return result;
 }
 
-void have_resist_sound(player_type *creature_ptr)
+BIT_FLAGS has_resist_sound(player_type *creature_ptr)
 {
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
-    creature_ptr->resist_sound = FALSE;
+    BIT_FLAGS result = 0L;
 
     if (creature_ptr->pclass == CLASS_BARD) {
-        creature_ptr->resist_sound = TRUE;
+        result |= 0x01U << FLAG_CAUSE_CLASS;
     }
 
     if (!creature_ptr->mimic_form && (creature_ptr->prace == RACE_CYCLOPS || creature_ptr->prace == RACE_BEASTMAN)) {
-        creature_ptr->resist_sound = TRUE;
+        result |= 0x01U << FLAG_CAUSE_RACE;
     }
 
-    if (creature_ptr->ult_res || (creature_ptr->special_defense & KATA_MUSOU)) {
-        creature_ptr->resist_sound = TRUE;
+    if (creature_ptr->special_defense & KATA_MUSOU) {
+        result |= 0x01U << FLAG_CAUSE_BATTLE_FORM;
     }
 
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
-
-        object_flags(creature_ptr, o_ptr, flgs);
-
-        if (have_flag(flgs, TR_RES_SOUND))
-            creature_ptr->resist_sound = TRUE;
+    if (creature_ptr->ult_res) {
+        result |= 0x01U << FLAG_CAUSE_MAGIC_TIME_EFFECT;
     }
+
+    result |= check_equipment_flags(creature_ptr, TR_RES_SOUND);
+    return result;
 }
 
-void have_resist_lite(player_type *creature_ptr)
+BIT_FLAGS has_resist_lite(player_type *creature_ptr)
 {
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
-    creature_ptr->resist_lite = FALSE;
+    BIT_FLAGS result = 0L;
 
     if (!creature_ptr->mimic_form && (creature_ptr->prace == RACE_ELF || creature_ptr->prace == RACE_HIGH_ELF || creature_ptr->prace == RACE_SPRITE)) {
-        creature_ptr->resist_lite = TRUE;
+        result |= 0x01U << FLAG_CAUSE_RACE;
     }
 
-    if (creature_ptr->ult_res || (creature_ptr->special_defense & KATA_MUSOU)) {
-        creature_ptr->resist_lite = TRUE;
+    if (creature_ptr->special_defense & KATA_MUSOU) {
+        result |= 0x01U << FLAG_CAUSE_BATTLE_FORM;
     }
 
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
+    if (creature_ptr->ult_res) {
+        result |= 0x01U << FLAG_CAUSE_MAGIC_TIME_EFFECT;
+    }
 
-        object_flags(creature_ptr, o_ptr, flgs);
+    result |= check_equipment_flags(creature_ptr, TR_RES_LITE);
+    return result;
+}
+
+BIT_FLAGS has_vuln_lite(player_type *creature_ptr)
+{
+    BIT_FLAGS result = 0L;
+    if (is_specific_player_race(creature_ptr, RACE_S_FAIRY) || is_specific_player_race(creature_ptr, RACE_VAMPIRE)
+        || (creature_ptr->mimic_form == MIMIC_VAMPIRE)) {
+        result |= 0x01U << FLAG_CAUSE_RACE;
+    }
 
-        if (have_flag(flgs, TR_RES_LITE))
-            creature_ptr->resist_lite = TRUE;
+    if (creature_ptr->wraith_form) {
+        result |= 0x01U << FLAG_CAUSE_MAGIC_TIME_EFFECT;
     }
+
+    return result;
 }
 
-void have_resist_dark(player_type *creature_ptr)
+BIT_FLAGS has_resist_dark(player_type *creature_ptr)
 {
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
-    creature_ptr->resist_dark = FALSE;
+    BIT_FLAGS result = 0L;
 
     if (creature_ptr->mimic_form == MIMIC_VAMPIRE) {
-        creature_ptr->resist_dark = TRUE;
+        result |= 0x01U << FLAG_CAUSE_RACE;
     }
 
     if (!creature_ptr->mimic_form
         && (creature_ptr->prace == RACE_HALF_ORC || creature_ptr->prace == RACE_HALF_OGRE || creature_ptr->prace == RACE_NIBELUNG
             || creature_ptr->prace == RACE_DARK_ELF || creature_ptr->prace == RACE_VAMPIRE)) {
-        creature_ptr->resist_lite = TRUE;
+        result |= 0x01U << FLAG_CAUSE_RACE;
     }
 
-    if (creature_ptr->ult_res || (creature_ptr->special_defense & KATA_MUSOU)) {
-        creature_ptr->resist_dark = TRUE;
+    if (creature_ptr->special_defense & KATA_MUSOU) {
+        result |= 0x01U << FLAG_CAUSE_BATTLE_FORM;
     }
 
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
-
-        object_flags(creature_ptr, o_ptr, flgs);
-
-        if (have_flag(flgs, TR_RES_DARK))
-            creature_ptr->resist_dark = TRUE;
+    if (creature_ptr->ult_res) {
+        result |= 0x01U << FLAG_CAUSE_MAGIC_TIME_EFFECT;
     }
+
+    result |= check_equipment_flags(creature_ptr, TR_RES_DARK);
+    return result;
 }
 
-void have_resist_chaos(player_type *creature_ptr)
+BIT_FLAGS has_resist_chaos(player_type *creature_ptr)
 {
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
-    creature_ptr->resist_chaos = FALSE;
+    BIT_FLAGS result = 0L;
 
     if (creature_ptr->pclass == CLASS_CHAOS_WARRIOR && creature_ptr->lev > 29)
-        creature_ptr->resist_chaos = TRUE;
+        result |= 0x01U << FLAG_CAUSE_CLASS;
 
     if (creature_ptr->mimic_form == MIMIC_DEMON || creature_ptr->mimic_form == MIMIC_DEMON_LORD) {
-        creature_ptr->resist_chaos = TRUE;
+        result |= 0x01U << FLAG_CAUSE_RACE;
     }
 
     if (!creature_ptr->mimic_form && creature_ptr->prace == RACE_HALF_TITAN)
-        creature_ptr->resist_chaos = TRUE;
+        result |= 0x01U << FLAG_CAUSE_RACE;
 
-    if (creature_ptr->ult_res || (creature_ptr->special_defense & KATA_MUSOU)) {
-        creature_ptr->resist_chaos = TRUE;
+    if (creature_ptr->special_defense & KATA_MUSOU) {
+        result |= 0x01U << FLAG_CAUSE_BATTLE_FORM;
     }
 
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
-
-        object_flags(creature_ptr, o_ptr, flgs);
-
-        if (have_flag(flgs, TR_RES_CHAOS))
-            creature_ptr->resist_chaos = TRUE;
+    if (creature_ptr->ult_res) {
+        result |= 0x01U << FLAG_CAUSE_MAGIC_TIME_EFFECT;
     }
+
+    result |= check_equipment_flags(creature_ptr, TR_RES_CHAOS);
+    return result;
 }
 
-void have_resist_disen(player_type *creature_ptr)
+BIT_FLAGS has_resist_disen(player_type *creature_ptr)
 {
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
-    creature_ptr->resist_disen = FALSE;
+    BIT_FLAGS result = 0L;
 
     if (creature_ptr->mimic_form == MIMIC_DEMON_LORD) {
-        creature_ptr->resist_disen = TRUE;
+        result |= 0x01U << FLAG_CAUSE_RACE;
     }
 
     if (!creature_ptr->mimic_form && creature_ptr->prace == RACE_NIBELUNG)
-        creature_ptr->resist_disen = TRUE;
+        result |= 0x01U << FLAG_CAUSE_RACE;
 
-    if (creature_ptr->ult_res || (creature_ptr->special_defense & KATA_MUSOU)) {
-        creature_ptr->resist_disen = TRUE;
+    if (creature_ptr->special_defense & KATA_MUSOU) {
+        result |= 0x01U << FLAG_CAUSE_BATTLE_FORM;
     }
 
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
-
-        object_flags(creature_ptr, o_ptr, flgs);
-
-        if (have_flag(flgs, TR_RES_DISEN))
-            creature_ptr->resist_disen = TRUE;
+    if (creature_ptr->ult_res) {
+        result |= 0x01U << FLAG_CAUSE_MAGIC_TIME_EFFECT;
     }
+
+    result |= check_equipment_flags(creature_ptr, TR_RES_DISEN);
+    return result;
 }
 
-void have_resist_shard(player_type *creature_ptr)
+BIT_FLAGS has_resist_shard(player_type *creature_ptr)
 {
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
-    creature_ptr->resist_shard = FALSE;
+    BIT_FLAGS result = 0L;
 
-    if (!creature_ptr->mimic_form && (creature_ptr->prace == RACE_HALF_TITAN || creature_ptr->prace == RACE_SKELETON))
-        creature_ptr->resist_shard = TRUE;
+    if (!creature_ptr->mimic_form && (creature_ptr->prace == RACE_HALF_GIANT || creature_ptr->prace == RACE_SKELETON))
+        result |= 0x01U << FLAG_CAUSE_RACE;
 
-    if (creature_ptr->ult_res || (creature_ptr->special_defense & KATA_MUSOU)) {
-        creature_ptr->resist_shard = TRUE;
+    if (creature_ptr->special_defense & KATA_MUSOU) {
+        result |= 0x01U << FLAG_CAUSE_BATTLE_FORM;
     }
 
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
-
-        object_flags(creature_ptr, o_ptr, flgs);
-
-        if (have_flag(flgs, TR_RES_DISEN))
-            creature_ptr->resist_shard = TRUE;
+    if (creature_ptr->ult_res) {
+        result |= 0x01U << FLAG_CAUSE_MAGIC_TIME_EFFECT;
     }
+
+    result |= check_equipment_flags(creature_ptr, TR_RES_SHARDS);
+    return result;
 }
 
-void have_resist_nexus(player_type *creature_ptr)
+BIT_FLAGS has_resist_nexus(player_type *creature_ptr)
 {
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
-    creature_ptr->resist_nexus = FALSE;
+    BIT_FLAGS result = 0L;
 
     if (creature_ptr->mimic_form == MIMIC_DEMON_LORD) {
-        creature_ptr->resist_nexus = TRUE;
+        result |= 0x01U << FLAG_CAUSE_RACE;
     }
 
-    if (creature_ptr->ult_res || (creature_ptr->special_defense & KATA_MUSOU)) {
-        creature_ptr->resist_nexus = TRUE;
+    if (creature_ptr->special_defense & KATA_MUSOU) {
+        result |= 0x01U << FLAG_CAUSE_BATTLE_FORM;
     }
 
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
-
-        object_flags(creature_ptr, o_ptr, flgs);
-
-        if (have_flag(flgs, TR_RES_NEXUS))
-            creature_ptr->resist_nexus = TRUE;
+    if (creature_ptr->ult_res) {
+        result |= 0x01U << FLAG_CAUSE_MAGIC_TIME_EFFECT;
     }
+
+    result |= check_equipment_flags(creature_ptr, TR_RES_NEXUS);
+    return result;
 }
 
-void have_resist_blind(player_type *creature_ptr)
+BIT_FLAGS has_resist_blind(player_type *creature_ptr)
 {
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
-    creature_ptr->resist_blind = FALSE;
+    BIT_FLAGS result = 0L;
 
     if (creature_ptr->pseikaku == PERSONALITY_MUNCHKIN) {
-        creature_ptr->resist_blind = TRUE;
+        result |= 0x01U << FLAG_CAUSE_PERSONALITY;
     }
 
     if (!creature_ptr->mimic_form && creature_ptr->prace == RACE_DWARF)
-        creature_ptr->resist_blind = TRUE;
+        result |= 0x01U << FLAG_CAUSE_RACE;
 
-    if (creature_ptr->ult_res || (creature_ptr->special_defense & KATA_MUSOU)) {
-        creature_ptr->resist_blind = TRUE;
+    if (creature_ptr->special_defense & KATA_MUSOU) {
+        result |= 0x01U << FLAG_CAUSE_BATTLE_FORM;
     }
 
-    if (creature_ptr->magicdef) {
-        creature_ptr->resist_blind = TRUE;
+    if (creature_ptr->ult_res || creature_ptr->magicdef) {
+        result |= 0x01U << FLAG_CAUSE_MAGIC_TIME_EFFECT;
     }
 
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
-
-        object_flags(creature_ptr, o_ptr, flgs);
-
-        if (have_flag(flgs, TR_RES_BLIND))
-            creature_ptr->resist_blind = TRUE;
-    }
+    result |= check_equipment_flags(creature_ptr, TR_RES_BLIND);
+    return result;
 }
 
-void have_resist_neth(player_type *creature_ptr)
+BIT_FLAGS has_resist_neth(player_type *creature_ptr)
 {
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
+    BIT_FLAGS result = 0L;
 
     if (creature_ptr->mimic_form == MIMIC_DEMON_LORD || creature_ptr->mimic_form == MIMIC_DEMON || creature_ptr->mimic_form == MIMIC_VAMPIRE) {
-        creature_ptr->resist_neth = TRUE;
+        result |= 0x01U << FLAG_CAUSE_RACE;
     }
 
     if (!creature_ptr->mimic_form
         && (creature_ptr->prace == RACE_ZOMBIE || creature_ptr->prace == RACE_VAMPIRE || creature_ptr->prace == RACE_SPECTRE
             || creature_ptr->prace == RACE_BALROG))
-        creature_ptr->resist_neth = TRUE;
+        result |= 0x01U << FLAG_CAUSE_RACE;
 
-    if (creature_ptr->ult_res || (creature_ptr->special_defense & KATA_MUSOU)) {
-        creature_ptr->resist_neth = TRUE;
+    if (creature_ptr->special_defense & KATA_MUSOU) {
+        result |= 0x01U << FLAG_CAUSE_BATTLE_FORM;
     }
 
-    if (creature_ptr->tim_res_nether) {
-        creature_ptr->resist_neth = TRUE;
+    if (creature_ptr->ult_res || creature_ptr->tim_res_nether) {
+        result |= 0x01U << FLAG_CAUSE_MAGIC_TIME_EFFECT;
     }
 
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
-
-        object_flags(creature_ptr, o_ptr, flgs);
-
-        if (have_flag(flgs, TR_RES_NETHER))
-            creature_ptr->resist_neth = TRUE;
-    }
+    result |= check_equipment_flags(creature_ptr, TR_RES_NETHER);
+    return result;
 }
 
-void have_resist_time(player_type *creature_ptr)
+BIT_FLAGS has_resist_time(player_type *creature_ptr)
 {
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
-    creature_ptr->resist_time = FALSE;
+    BIT_FLAGS result = 0L;
 
     if (creature_ptr->tim_res_time) {
-        creature_ptr->resist_time = TRUE;
+        result |= 0x01U << FLAG_CAUSE_MAGIC_TIME_EFFECT;
     }
 
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
-
-        object_flags(creature_ptr, o_ptr, flgs);
-        if (o_ptr->name2 == EGO_RING_RES_TIME)
-            creature_ptr->resist_time = TRUE;
-    }
+    result |= check_equipment_flags(creature_ptr, TR_RES_TIME);
+    return result;
 }
 
-void have_resist_water(player_type *creature_ptr)
+BIT_FLAGS has_resist_water(player_type *creature_ptr)
 {
-    creature_ptr->resist_water = FALSE;
+    BIT_FLAGS result = 0L;
 
     if (!creature_ptr->mimic_form && creature_ptr->prace == RACE_MERFOLK)
-        creature_ptr->resist_water = TRUE;
+        result |= 0x01U << FLAG_CAUSE_RACE;
+
+    result |= check_equipment_flags(creature_ptr, TR_RES_WATER);
+    return result;
 }
 
-void have_resist_fear(player_type *creature_ptr)
+BIT_FLAGS has_resist_fear(player_type *creature_ptr)
 {
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
-    creature_ptr->resist_fear = FALSE;
+    BIT_FLAGS result = 0L;
 
     if (creature_ptr->muta3 & MUT3_FEARLESS)
-        creature_ptr->resist_fear = TRUE;
+        result |= 0x01U << FLAG_CAUSE_MUTATION;
 
     switch (creature_ptr->pclass) {
     case CLASS_WARRIOR:
+    case CLASS_SAMURAI:
         if (creature_ptr->lev > 29)
-            creature_ptr->resist_fear = TRUE;
+            result |= 0x01U << FLAG_CAUSE_CLASS;
         break;
     case CLASS_PALADIN:
-        if (creature_ptr->lev > 39)
-            creature_ptr->resist_fear = TRUE;
-        break;
     case CLASS_CHAOS_WARRIOR:
         if (creature_ptr->lev > 39)
-            creature_ptr->resist_fear = TRUE;
+            result |= 0x01U << FLAG_CAUSE_CLASS;
         break;
     case CLASS_MINDCRAFTER:
         if (creature_ptr->lev > 9)
-            creature_ptr->resist_fear = TRUE;
-        break;
-    case CLASS_SAMURAI:
-        if (creature_ptr->lev > 29)
-            creature_ptr->resist_fear = TRUE;
+            result |= 0x01U << FLAG_CAUSE_CLASS;
         break;
     case CLASS_NINJA:
-        creature_ptr->resist_fear = TRUE;
+        result |= 0x01U << FLAG_CAUSE_CLASS;
         break;
     }
 
     if (creature_ptr->mimic_form == MIMIC_DEMON_LORD) {
-        creature_ptr->resist_fear = TRUE;
+        result |= 0x01U << FLAG_CAUSE_RACE;
     }
 
     if (!creature_ptr->mimic_form && creature_ptr->prace == RACE_BARBARIAN)
-        creature_ptr->resist_fear = TRUE;
+        result |= 0x01U << FLAG_CAUSE_RACE;
 
-    if (creature_ptr->ult_res || (creature_ptr->special_defense & KATA_MUSOU)) {
-        creature_ptr->resist_fear = TRUE;
+    if ((creature_ptr->special_defense & KATA_MUSOU)) {
+        result |= 0x01U << FLAG_CAUSE_BATTLE_FORM;
     }
 
-    if (is_hero(creature_ptr) || creature_ptr->shero) {
-        creature_ptr->resist_fear = TRUE;
+    if (is_hero(creature_ptr) || is_shero(creature_ptr) || creature_ptr->ult_res) {
+        result |= 0x01U << FLAG_CAUSE_MAGIC_TIME_EFFECT;
     }
 
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
-
-        object_flags(creature_ptr, o_ptr, flgs);
-        if (have_flag(flgs, TR_RES_FEAR))
-            creature_ptr->resist_fear = TRUE;
-    }
+    result |= check_equipment_flags(creature_ptr, TR_RES_FEAR);
+    return result;
 }
 
-void have_immune_acid(player_type *creature_ptr)
+BIT_FLAGS has_immune_acid(player_type *creature_ptr)
 {
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
-    creature_ptr->immune_acid = FALSE;
-
+    BIT_FLAGS result = 0L;
     if (!creature_ptr->mimic_form && creature_ptr->prace == RACE_YEEK && creature_ptr->lev > 19)
-        creature_ptr->immune_acid = TRUE;
+        result |= 0x01U << FLAG_CAUSE_RACE;
 
     if (creature_ptr->ele_immune) {
         if (creature_ptr->special_defense & DEFENSE_ACID)
-            creature_ptr->immune_acid = TRUE;
+            result |= 0x01U << FLAG_CAUSE_MAGIC_TIME_EFFECT;
     }
 
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
-
-        object_flags(creature_ptr, o_ptr, flgs);
-        if (have_flag(flgs, TR_IM_ACID))
-            creature_ptr->immune_acid = TRUE;
-    }
+    result |= check_equipment_flags(creature_ptr, TR_IM_ACID);
+    return result;
 }
 
-void have_immune_elec(player_type *creature_ptr)
+BIT_FLAGS has_immune_elec(player_type *creature_ptr)
 {
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
-    creature_ptr->immune_elec = FALSE;
+    BIT_FLAGS result = 0L;
+
     if (creature_ptr->ele_immune) {
         if (creature_ptr->special_defense & DEFENSE_ELEC)
-            creature_ptr->immune_elec = TRUE;
+            result |= 0x01U << FLAG_CAUSE_MAGIC_TIME_EFFECT;
     }
 
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
-
-        object_flags(creature_ptr, o_ptr, flgs);
-        if (have_flag(flgs, TR_IM_ELEC))
-            creature_ptr->immune_elec = TRUE;
-    }
+    result |= check_equipment_flags(creature_ptr, TR_IM_ELEC);
+    return result;
 }
 
-void have_immune_fire(player_type *creature_ptr)
+BIT_FLAGS has_immune_fire(player_type *creature_ptr)
 {
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
-    creature_ptr->immune_fire = FALSE;
+    BIT_FLAGS result = 0L;
+
     if (creature_ptr->ele_immune) {
         if (creature_ptr->special_defense & DEFENSE_FIRE)
-            creature_ptr->immune_fire = TRUE;
+            result |= 0x01U << FLAG_CAUSE_MAGIC_TIME_EFFECT;
     }
 
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
-
-        object_flags(creature_ptr, o_ptr, flgs);
-        if (have_flag(flgs, TR_IM_FIRE))
-            creature_ptr->immune_fire = TRUE;
-    }
+    result |= check_equipment_flags(creature_ptr, TR_IM_FIRE);
+    return result;
 }
 
-void have_immune_cold(player_type *creature_ptr)
+BIT_FLAGS has_immune_cold(player_type *creature_ptr)
 {
-    object_type *o_ptr;
-    BIT_FLAGS flgs[TR_FLAG_SIZE];
-    creature_ptr->immune_cold = FALSE;
+    BIT_FLAGS result = 0L;
+
     if (creature_ptr->ele_immune) {
         if (creature_ptr->special_defense & DEFENSE_COLD)
-            creature_ptr->immune_cold = TRUE;
+            result |= 0x01U << FLAG_CAUSE_MAGIC_TIME_EFFECT;
     }
 
-    for (inventory_slot_type i = INVEN_RARM; i < INVEN_TOTAL; i++) {
-        o_ptr = &creature_ptr->inventory_list[i];
-        if (!o_ptr->k_idx)
-            continue;
+    result |= check_equipment_flags(creature_ptr, TR_IM_COLD);
+    return result;
+}
 
-        object_flags(creature_ptr, o_ptr, flgs);
-        if (have_flag(flgs, TR_IM_COLD))
-            creature_ptr->immune_cold = TRUE;
+BIT_FLAGS has_immune_dark(player_type *creature_ptr)
+{
+    BIT_FLAGS result = 0L;
+
+    if (is_specific_player_race(creature_ptr, RACE_VAMPIRE) || (creature_ptr->mimic_form == MIMIC_VAMPIRE)) {
+        result |= 0x01U << FLAG_CAUSE_RACE;
+    }
+
+    if (creature_ptr->wraith_form) {
+        result |= 0x01U << FLAG_CAUSE_MAGIC_TIME_EFFECT;
     }
+
+    return result;
 }
 
-bool have_right_hand_weapon(player_type *creature_ptr)
+melee_type player_melee_type(player_type *creature_ptr)
 {
-    if (has_melee_weapon(creature_ptr, INVEN_RARM))
-        return TRUE;
+    if (has_two_handed_weapons(creature_ptr))
+        return MELEE_TYPE_WEAPON_TWOHAND;
 
-    if (can_two_hands_wielding(creature_ptr)) {
-        switch (creature_ptr->pclass) {
-        case CLASS_MONK:
-        case CLASS_FORCETRAINER:
-        case CLASS_BERSERKER:
-            if (empty_hands(creature_ptr, FALSE) == (EMPTY_HAND_RARM | EMPTY_HAND_LARM)) {
-                return TRUE;
-            }
-            break;
+    if (has_melee_weapon(creature_ptr, INVEN_MAIN_HAND)) {
+        if (has_melee_weapon(creature_ptr, INVEN_SUB_HAND)) {
+            return MELEE_TYPE_WEAPON_DOUBLE;
         }
+        return MELEE_TYPE_WEAPON_MAIN;
     }
 
-       return FALSE;
+    if (has_melee_weapon(creature_ptr, INVEN_SUB_HAND))
+        return MELEE_TYPE_WEAPON_SUB;
+
+    if (empty_hands(creature_ptr, FALSE) == (EMPTY_HAND_MAIN | EMPTY_HAND_SUB))
+        return MELEE_TYPE_BAREHAND_TWO;
+
+    if (empty_hands(creature_ptr, FALSE) == EMPTY_HAND_MAIN)
+        return MELEE_TYPE_BAREHAND_MAIN;
+
+    if (empty_hands(creature_ptr, FALSE) == EMPTY_HAND_SUB)
+        return MELEE_TYPE_BAREHAND_SUB;
+
+    return MELEE_TYPE_SHIELD_DOUBLE;
 }
 
-bool have_left_hand_weapon(player_type *creature_ptr)
+/*
+ * @brief 利き手で攻撃可能かどうかを判定する
+ *        利き手で攻撃可能とは、利き手に武器を持っているか、
+ *        利き手が素手かつ左手も素手もしくは盾を装備している事を意味する。
+ * @detail Includes martial arts and hand combats as weapons.
+ */
+bool can_attack_with_main_hand(player_type *creature_ptr)
 {
-    return has_melee_weapon(creature_ptr, INVEN_LARM);
+    if (has_melee_weapon(creature_ptr, INVEN_MAIN_HAND))
+        return TRUE;
+
+    if ((empty_hands(creature_ptr, TRUE) & EMPTY_HAND_MAIN) && !can_attack_with_sub_hand(creature_ptr))
+        return TRUE;
+
+    return FALSE;
 }
 
-bool have_two_handed_weapons(player_type *creature_ptr)
+/*
+ * @brief 非利き手で攻撃可能かどうかを判定する
+ *        非利き手で攻撃可能とは、非利き手に武器を持っている事に等しい
+ * @detail Exclude martial arts and hand combats from weapons.
+ */
+bool can_attack_with_sub_hand(player_type *creature_ptr) { return has_melee_weapon(creature_ptr, INVEN_SUB_HAND); }
+
+/*
+ * @brief 両手持ち状態かどうかを判定する
+ */
+bool has_two_handed_weapons(player_type *creature_ptr)
 {
     if (can_two_hands_wielding(creature_ptr)) {
-        if (have_right_hand_weapon(creature_ptr) && (empty_hands(creature_ptr, FALSE) == EMPTY_HAND_LARM)
-            && object_allow_two_hands_wielding(&creature_ptr->inventory_list[INVEN_RARM])) {
+        if (can_attack_with_main_hand(creature_ptr) && (empty_hands(creature_ptr, FALSE) == EMPTY_HAND_SUB)
+            && object_allow_two_hands_wielding(&creature_ptr->inventory_list[INVEN_MAIN_HAND])) {
             return TRUE;
-        } else if (have_left_hand_weapon(creature_ptr) && (empty_hands(creature_ptr, FALSE) == EMPTY_HAND_RARM)
-            && object_allow_two_hands_wielding(&creature_ptr->inventory_list[INVEN_LARM])) {
+        } else if (can_attack_with_sub_hand(creature_ptr) && (empty_hands(creature_ptr, FALSE) == EMPTY_HAND_MAIN)
+            && object_allow_two_hands_wielding(&creature_ptr->inventory_list[INVEN_SUB_HAND])) {
             return TRUE;
         }
     }
     return FALSE;
 }
 
-void have_lite(player_type *creature_ptr)
+BIT_FLAGS has_lite(player_type *creature_ptr)
 {
-    creature_ptr->lite = FALSE;
+    BIT_FLAGS result = 0L;
     if (creature_ptr->pclass == CLASS_NINJA)
-        return;
+        return 0L;
 
     if (creature_ptr->pseikaku == PERSONALITY_MUNCHKIN) {
-        creature_ptr->lite = TRUE;
+        result |= 0x01U << FLAG_CAUSE_PERSONALITY;
     }
 
     if (creature_ptr->mimic_form == MIMIC_VAMPIRE) {
-        creature_ptr->lite = TRUE;
-    }
-
-    if (creature_ptr->muta3 & MUT3_FIRE_BODY) {
-        creature_ptr->lite = TRUE;
+        result |= 0x01U << FLAG_CAUSE_RACE;
     }
 
     if (!creature_ptr->mimic_form && creature_ptr->prace == RACE_VAMPIRE)
-        creature_ptr->lite = TRUE;
+        result |= 0x01U << FLAG_CAUSE_RACE;
 
-    if (creature_ptr->sh_fire)
-        creature_ptr->lite = TRUE;
+    if (creature_ptr->ult_res) {
+        result |= 0x01U << FLAG_CAUSE_MAGIC_TIME_EFFECT;
+    }
 
-    if (creature_ptr->ult_res || (creature_ptr->special_defense & KATA_MUSOU)) {
-        creature_ptr->lite = TRUE;
+    if (creature_ptr->special_defense & KATA_MUSOU) {
+        result |= 0x01U << FLAG_CAUSE_BATTLE_FORM;
     }
+
+    result |= has_sh_fire(creature_ptr);
+
+    return result;
 }
 
-bool is_disable_two_handed_bonus(player_type *creature_ptr, int i)
+/*
+ * @brief 両手持ちボーナスがもらえないかどうかを判定する。 / Does *not * get two hand wielding bonus.
+ * @detail
+ *  Only can get hit bonuses when wieids an enough light weapon which is lighter than 5 times of weight limit.
+ *  If its weight is 10 times heavier or more than weight limit, gets hit penalty in calc_to_hit().
+ */
+bool has_disable_two_handed_bonus(player_type *creature_ptr, int i)
 {
-    object_type *o_ptr;
-    o_ptr = &creature_ptr->inventory_list[INVEN_RARM + i];
-    if (has_melee_weapon(creature_ptr, INVEN_RARM + i)) {
-        if (calc_weapon_weight_limit(creature_ptr) * 2 >= o_ptr->weight / 10 && have_two_handed_weapons(creature_ptr) && (calc_weapon_weight_limit(creature_ptr) * 2 < o_ptr->weight / 5))
-            return TRUE;
+    if (has_melee_weapon(creature_ptr, INVEN_MAIN_HAND + i) && has_two_handed_weapons(creature_ptr)) {
+        object_type *o_ptr = &creature_ptr->inventory_list[INVEN_MAIN_HAND + i];
+        int limit = calc_weapon_weight_limit(creature_ptr) * 2;
+
+        /* Enable when two hand wields an enough light weapon */
+        if (limit >= o_ptr->weight / 5)
+            return FALSE;
     }
-    return FALSE;
+
+    /* Disable when empty hands, one hand wieldings and heavy weapons */
+    return TRUE;
 }
 
-bool is_icky_wield_weapon(player_type *creature_ptr, int i)
+/*
+ * todo 相応しい時にFALSEで相応しくない時にTRUEという負論理は良くない、後で修正する
+ */
+bool has_icky_wield_weapon(player_type *creature_ptr, int i)
 {
-    object_type *o_ptr;
     BIT_FLAGS flgs[TR_FLAG_SIZE];
-    o_ptr = &creature_ptr->inventory_list[INVEN_RARM + i];
+    object_type *o_ptr = &creature_ptr->inventory_list[INVEN_MAIN_HAND + i];
     object_flags(creature_ptr, o_ptr, flgs);
 
-    if ((creature_ptr->pclass == CLASS_PRIEST) && (!(have_flag(flgs, TR_BLESSED))) && ((o_ptr->tval == TV_SWORD) || (o_ptr->tval == TV_POLEARM))) {
-        return TRUE;
-    } else if (creature_ptr->pclass == CLASS_SORCERER) {
-        if (!((o_ptr->tval == TV_HAFTED) && ((o_ptr->sval == SV_WIZSTAFF) || (o_ptr->sval == SV_NAMAKE_HAMMER)))) {
-            return TRUE;
-        }
+    bool has_no_weapon = (o_ptr->tval == TV_NONE) || (o_ptr->tval == TV_SHIELD);
+    if (creature_ptr->pclass == CLASS_PRIEST) {
+        bool is_suitable_weapon = has_flag(flgs, TR_BLESSED);
+        is_suitable_weapon |= (o_ptr->tval != TV_SWORD) && (o_ptr->tval != TV_POLEARM);
+        return !has_no_weapon && !is_suitable_weapon;
     }
-    if (is_not_monk_weapon(creature_ptr, i) || is_not_ninja_weapon(creature_ptr, i)) {
-        return TRUE;
+
+    if (creature_ptr->pclass == CLASS_SORCERER) {
+        bool is_suitable_weapon = o_ptr->tval == TV_HAFTED;
+        is_suitable_weapon &= (o_ptr->sval == SV_WIZSTAFF) || (o_ptr->sval == SV_NAMAKE_HAMMER);
+        return !has_no_weapon && !is_suitable_weapon;
     }
+
+    if (has_not_monk_weapon(creature_ptr, i) || has_not_ninja_weapon(creature_ptr, i))
+        return TRUE;
+
     return FALSE;
 }
 
-bool is_riding_wield_weapon(player_type *creature_ptr, int i)
+bool has_riding_wield_weapon(player_type *creature_ptr, int i)
 {
     object_type *o_ptr;
     BIT_FLAGS flgs[TR_FLAG_SIZE];
-    o_ptr = &creature_ptr->inventory_list[INVEN_RARM + i];
+    o_ptr = &creature_ptr->inventory_list[INVEN_MAIN_HAND + i];
     object_flags(creature_ptr, o_ptr, flgs);
     if (creature_ptr->riding != 0 && !(o_ptr->tval == TV_POLEARM) && ((o_ptr->sval == SV_LANCE) || (o_ptr->sval == SV_HEAVY_LANCE))
-        && !have_flag(flgs, TR_RIDING)) {
+        && !has_flag(flgs, TR_RIDING)) {
         return TRUE;
     }
     return FALSE;
 }
 
-bool is_not_ninja_weapon(player_type *creature_ptr, int i)
+bool has_not_ninja_weapon(player_type *creature_ptr, int i)
 {
-    tval_type tval = creature_ptr->inventory_list[INVEN_RARM + i].tval - TV_WEAPON_BEGIN;
-    OBJECT_SUBTYPE_VALUE sval = creature_ptr->inventory_list[INVEN_RARM + i].sval;
+    if (!has_melee_weapon(creature_ptr, INVEN_MAIN_HAND + i)) {
+        return FALSE;
+    }
+    tval_type tval = creature_ptr->inventory_list[INVEN_MAIN_HAND + i].tval - TV_WEAPON_BEGIN;
+    OBJECT_SUBTYPE_VALUE sval = creature_ptr->inventory_list[INVEN_MAIN_HAND + i].sval;
     return creature_ptr->pclass == CLASS_NINJA
-        && !((s_info[CLASS_NINJA].w_max[tval][sval] > WEAPON_EXP_BEGINNER) && (creature_ptr->inventory_list[INVEN_LARM - i].tval != TV_SHIELD));
+        && !((s_info[CLASS_NINJA].w_max[tval][sval] > WEAPON_EXP_BEGINNER) && (creature_ptr->inventory_list[INVEN_SUB_HAND - i].tval != TV_SHIELD));
 }
 
-bool is_not_monk_weapon(player_type *creature_ptr, int i)
+bool has_not_monk_weapon(player_type *creature_ptr, int i)
 {
-    tval_type tval = creature_ptr->inventory_list[INVEN_RARM + i].tval - TV_WEAPON_BEGIN;
-    OBJECT_SUBTYPE_VALUE sval = creature_ptr->inventory_list[INVEN_RARM + i].sval;
-    return (creature_ptr->pclass == CLASS_MONK) || (creature_ptr->pclass == CLASS_FORCETRAINER) && (!s_info[creature_ptr->pclass].w_max[tval][sval]);
+    if (!has_melee_weapon(creature_ptr, INVEN_MAIN_HAND + i)) {
+        return FALSE;
+    }
+    tval_type tval = creature_ptr->inventory_list[INVEN_MAIN_HAND + i].tval - TV_WEAPON_BEGIN;
+    OBJECT_SUBTYPE_VALUE sval = creature_ptr->inventory_list[INVEN_MAIN_HAND + i].sval;
+    return ((creature_ptr->pclass == CLASS_MONK) || (creature_ptr->pclass == CLASS_FORCETRAINER)) && !(s_info[creature_ptr->pclass].w_max[tval][sval]);
+}
+
+bool has_good_luck(player_type *creature_ptr) { return (creature_ptr->pseikaku == PERSONALITY_LUCKY) || (creature_ptr->muta3 & MUT3_GOOD_LUCK); }
+
+BIT_FLAGS player_aggravate_state(player_type *creature_ptr)
+{
+    if (creature_ptr->cursed & TRC_AGGRAVATE) {
+        if ((is_specific_player_race(creature_ptr, RACE_S_FAIRY)) && (creature_ptr->pseikaku != PERSONALITY_SEXY)) {
+            return AGGRAVATE_S_FAIRY;
+        }
+        return AGGRAVATE_NORMAL;
+    }
+
+    return AGGRAVATE_NONE;
 }
 
-bool have_good_luck(player_type *creature_ptr) { return (creature_ptr->pseikaku == PERSONALITY_LUCKY) || (creature_ptr->muta3 |= MUT3_GOOD_LUCK); };
+bool has_aggravate(player_type *creature_ptr) { return player_aggravate_state(creature_ptr) == AGGRAVATE_NORMAL; }