add old trigger effect rule in rule<=4

field.cpp

@@ -3356,6 +3356,25 @@ int32 field::check_hand_trigger(chain& ch) {
 	}
 	return TRUE;
 }
+int32 field::check_trigger_effect(const chain& ch) const {
+	effect* peffect = ch.triggering_effect;
+	card* phandler = peffect->get_handler();
+	if(core.duel_rule >= 5)
+		return phandler->is_has_relation(ch);
+	else {
+		if(peffect->type & EFFECT_TYPE_FIELD)
+			return phandler->is_has_relation(ch);
+		else {
+			if((ch.triggering_location & (LOCATION_DECK | LOCATION_HAND | LOCATION_EXTRA))
+				&& (ch.triggering_position & POS_FACEDOWN))
+				return TRUE;
+			if(!(phandler->current.location & (LOCATION_DECK | LOCATION_HAND | LOCATION_EXTRA))
+				|| phandler->is_position(POS_FACEUP))
+				return TRUE;
+			return FALSE;
+		}
+	}
+}
 int32 field::check_spself_from_hand_trigger(const chain& ch) const {
 	effect* peffect = ch.triggering_effect;
 	uint8 tp = ch.triggering_player;

field.h

@@ -482,6 +482,7 @@ public:
 	int32 get_cteffect_evt(effect* feffect, int32 playerid, const tevent& e, int32 store);
 	int32 check_cteffect_hint(effect* peffect, uint8 playerid);
 	int32 check_hand_trigger(chain& ch);
+	int32 check_trigger_effect(const chain& ch) const;
 	int32 check_spself_from_hand_trigger(const chain& ch) const;
 	int32 is_able_to_enter_bp();
 

processor.cpp

@@ -1310,7 +1310,7 @@ int32 field::process_point_event(int16 step, int32 skip_trigger, int32 skip_free
 			if(phandler->is_has_relation(*clit)) //work around: position and control should be refreshed before raising event
 				clit->set_triggering_state(phandler);
 			uint8 tp = clit->triggering_player;
-			if(phandler->is_has_relation(*clit) && peffect->is_chainable(tp) && peffect->is_activateable(tp, clit->evt, TRUE)) {
+			if(check_trigger_effect(*clit) && peffect->is_chainable(tp) && peffect->is_activateable(tp, clit->evt, TRUE)) {
 				if(tp == core.current_player)
 					core.select_chains.push_back(*clit);
 			} else {
@@ -1367,7 +1367,7 @@ int32 field::process_point_event(int16 step, int32 skip_trigger, int32 skip_free
 				clit->set_triggering_state(phandler);
 			}
 			uint8 tp = clit->triggering_player;
-			if(check_hand_trigger(*clit) && phandler->is_has_relation(*clit)
+			if(check_hand_trigger(*clit) && check_trigger_effect(*clit)
 				&& peffect->is_chainable(tp) && peffect->is_activateable(tp, clit->evt, TRUE)
 				&& check_spself_from_hand_trigger(*clit)) {
 				if(tp == core.current_player)