Group "immortal" also protects players from damage

Document new meaning of immortal=1 for players

Disable breathing if player is immortal

Hide builtin statbars if player immortal (delayed)

Co-authored-by: ClobberXD <ClobberXD@gmail.com>

builtin/game/statbars.lua

@@ -50,7 +50,8 @@ local function update_builtin_statbars(player)
 	end
 	local hud = hud_ids[name]
 
-	if flags.healthbar and enable_damage then
+	local immortal = player:get_armor_groups().immortal == 1
+	if flags.healthbar and enable_damage and not immortal then
 		local number = scaleToDefault(player, "hp")
  		if hud.id_healthbar == nil then
  			local hud_def = table.copy(health_bar_definition)
@@ -65,7 +66,7 @@ local function update_builtin_statbars(player)
 	end
 
 	local breath_max = player:get_properties().breath_max
-	if flags.breathbar and enable_damage and
+	if flags.breathbar and enable_damage and not immortal and
 			player:get_breath() < breath_max then
 		local number = 2 * scaleToDefault(player, "breath")
 		if hud.id_breathbar == nil then
@@ -116,7 +117,7 @@ local function player_event_handler(player,eventname)
 		end
 	end
 
-	if eventname == "hud_changed" then
+	if eventname == "hud_changed" or eventname == "properties_changed" then
 		update_builtin_statbars(player)
 		return true
 	end

doc/lua_api.txt

@@ -1533,7 +1533,9 @@ Another example: Make red wool from white wool and red dye:
 Special groups
 --------------
 
-* `immortal`: Disables the group damage system for an entity
+* `immortal`: Skips all damage and breath handling for an object. This group
+  will also hide the integrated HUD status bars for players, and is
+  automatically set to all players when damage is disabled on the server.
 * `punch_operable`: For entities; disables the regular damage mechanism for
   players punching it by hand or a non-tool item, so that it can do something
   else than take damage.

src/content_sao.cpp

@@ -134,7 +134,7 @@ void UnitSAO::setArmorGroups(const ItemGroupList &armor_groups)
 	m_armor_groups_sent = false;
 }
 
-const ItemGroupList &UnitSAO::getArmorGroups()
+const ItemGroupList &UnitSAO::getArmorGroups() const
 {
 	return m_armor_groups;
 }
@@ -1015,14 +1015,14 @@ void PlayerSAO::step(float dtime, bool send_recommended)
 		}
 	}
 
-	if (m_breathing_interval.step(dtime, 0.5f)) {
+	if (m_breathing_interval.step(dtime, 0.5f) && !isImmortal()) {
 		// Get nose/mouth position, approximate with eye position
 		v3s16 p = floatToInt(getEyePosition(), BS);
 		MapNode n = m_env->getMap().getNodeNoEx(p);
 		const ContentFeatures &c = m_env->getGameDef()->ndef()->get(n);
-		// If player is alive & no drowning & not in ignore, breathe
+		// If player is alive & not drowning & not in ignore & not immortal, breathe
-		if (m_breath < m_prop.breath_max &&
+		if (m_breath < m_prop.breath_max && c.drowning == 0 &&
-				c.drowning == 0 && n.getContent() != CONTENT_IGNORE && m_hp > 0)
+				n.getContent() != CONTENT_IGNORE && m_hp > 0)
 			setBreath(m_breath + 1);
 	}
 
@@ -1069,6 +1069,7 @@ void PlayerSAO::step(float dtime, bool send_recommended)
 		// create message and add to list
 		ActiveObjectMessage aom(getId(), true, str);
 		m_messages_out.push(aom);
+		m_env->getScriptIface()->player_event(this, "properties_changed");
 	}
 
 	// If attached, check that our parent is still there. If it isn't, detach.
@@ -1287,8 +1288,8 @@ int PlayerSAO::punch(v3f dir,
 
 	FATAL_ERROR_IF(!puncher, "Punch action called without SAO");
 
-	// No effect if PvP disabled
+	// No effect if PvP disabled or if immortal
-	if (!g_settings->getBool("enable_pvp")) {
+	if (isImmortal() || !g_settings->getBool("enable_pvp")) {
 		if (puncher->getType() == ACTIVEOBJECT_TYPE_PLAYER) {
 			std::string str = gob_cmd_punched(getHP());
 			// create message and add to list

src/content_sao.h

@@ -45,11 +45,12 @@ public:
 
 	inline bool isAttached() const
 	{ return getParent(); }
+
 	inline bool isImmortal() const
-	{ return itemgroup_get(m_armor_groups, "immortal"); }
+	{ return itemgroup_get(getArmorGroups(), "immortal"); }
 
 	void setArmorGroups(const ItemGroupList &armor_groups);
-	const ItemGroupList &getArmorGroups();
+	const ItemGroupList &getArmorGroups() const;
 	void setAnimation(v2f frame_range, float frame_speed, float frame_blend, bool frame_loop);
 	void getAnimation(v2f *frame_range, float *frame_speed, float *frame_blend, bool *frame_loop);
 	void setAnimationSpeed(float frame_speed);
@@ -107,7 +108,7 @@ class LuaEntitySAO : public UnitSAO
 {
 public:
 	LuaEntitySAO(ServerEnvironment *env, v3f pos,
-	             const std::string &name, const std::string &state);
+		const std::string &name, const std::string &state);
 	~LuaEntitySAO();
 	ActiveObjectType getType() const
 	{ return ACTIVEOBJECT_TYPE_LUAENTITY; }
@@ -115,16 +116,16 @@ public:
 	{ return ACTIVEOBJECT_TYPE_GENERIC; }
 	virtual void addedToEnvironment(u32 dtime_s);
 	static ServerActiveObject* create(ServerEnvironment *env, v3f pos,
-			const std::string &data);
+		const std::string &data);
 	void step(float dtime, bool send_recommended);
 	std::string getClientInitializationData(u16 protocol_version);
 	bool isStaticAllowed() const
 	{ return m_prop.static_save; }
 	void getStaticData(std::string *result) const;
 	int punch(v3f dir,
-			const ToolCapabilities *toolcap=NULL,
+		const ToolCapabilities *toolcap = nullptr,
-			ServerActiveObject *puncher=NULL,
+		ServerActiveObject *puncher = nullptr,
-			float time_from_last_punch=1000000);
+		float time_from_last_punch = 1000000);
 	void rightClick(ServerActiveObject *clicker);
 	void setPos(const v3f &pos);
 	void moveTo(v3f pos, bool continuous);
@@ -132,6 +133,7 @@ public:
 	std::string getDescription();
 	void setHP(s32 hp, const PlayerHPChangeReason &reason);
 	u16 getHP() const;
+
 	/* LuaEntitySAO-specific */
 	void setVelocity(v3f velocity);
 	void addVelocity(v3f velocity)

src/server.cpp

@@ -1429,7 +1429,7 @@ void Server::SendPlayerHPOrDie(PlayerSAO *playersao, const PlayerHPChangeReason
 	if (playersao->isImmortal())
 		return;
 
-	session_t peer_id   = playersao->getPeerID();
+	session_t peer_id = playersao->getPeerID();
 	bool is_alive = playersao->getHP() > 0;
 
 	if (is_alive)