fix: party shared experience (#3133)

This fixes the party shared experience that was not providing the correct amount of experience giving the unique vocations count and party size.

data/events/scripts/party.lua

@@ -66,25 +66,14 @@ function Party:onDisband()
 end
 
 function Party:onShareExperience(exp)
-	local sharedExperienceMultiplier = 1.20 --20%
-	local vocationsIds = {}
+	local uniqueVocationsCount = self:getUniqueVocationsCount()
+	local partySize = self:getMemberCount() + 1
 
-	local vocationId = self:getLeader():getVocation():getBase():getId()
-	if vocationId ~= VOCATION_NONE then
-		table.insert(vocationsIds, vocationId)
-	end
-
-	for _, member in ipairs(self:getMembers()) do
-		vocationId = member:getVocation():getBase():getId()
-		if not table.contains(vocationsIds, vocationId) and vocationId ~= VOCATION_NONE then
-			table.insert(vocationsIds, vocationId)
-		end
-	end
-
-	local size = #vocationsIds
-	if size > 1 then
-		sharedExperienceMultiplier = 1.0 + ((size * (5 * (size - 1) + 10)) / 100)
-	end
+	-- Formula to calculate the % based on the vocations amount
+	local sharedExperienceMultiplier = ((0.1 * (uniqueVocationsCount ^ 2)) - (0.2 * uniqueVocationsCount) + 1.3)
+	-- Since the formula its non linear, we need to subtract 0.1 if all vocations are present,
+	-- because on all vocations the multiplier is 2.1 and it should be 2.0
+	sharedExperienceMultiplier = partySize < 4 and sharedExperienceMultiplier or sharedExperienceMultiplier - 0.1
 
-	return math.ceil((exp * sharedExperienceMultiplier) / (#self:getMembers() + 1))
+	return math.ceil((exp * sharedExperienceMultiplier) / partySize)
 end

src/creatures/players/grouping/party.cpp

@@ -12,6 +12,7 @@
 #include "config/configmanager.hpp"
 #include "creatures/creature.hpp"
 #include "creatures/players/player.hpp"
+#include "creatures/players/vocations/vocation.hpp"
 #include "game/game.hpp"
 #include "game/movement/position.hpp"
 #include "lua/callbacks/event_callback.hpp"
@@ -61,6 +62,25 @@ size_t Party::getInvitationCount() const {
 	return inviteList.size();
 }
 
+uint8_t Party::getUniqueVocationsCount() const {
+	std::unordered_set<uint8_t> uniqueVocations;
+
+	for (const auto &player : getPlayers()) {
+		if (uniqueVocations.size() >= 4) {
+			break;
+		}
+
+		const auto &vocation = player->getVocation();
+		if (!vocation) {
+			continue;
+		}
+
+		uniqueVocations.insert(vocation->getBaseId());
+	}
+
+	return uniqueVocations.size();
+}
+
 void Party::disband() {
 	if (!g_events().eventPartyOnDisband(getParty())) {
 		return;
@@ -504,9 +524,11 @@ void Party::shareExperience(uint64_t experience, const std::shared_ptr<Creature>
 	g_callbacks().executeCallback(EventCallback_t::partyOnShareExperience, &EventCallback::partyOnShareExperience, getParty(), std::ref(shareExperience));
 
 	for (const auto &member : getMembers()) {
-		member->onGainSharedExperience(shareExperience, target);
+		const auto memberStaminaBoost = static_cast<float>(member->getStaminaXpBoost()) / 100;
+		member->onGainSharedExperience(shareExperience * memberStaminaBoost, target);
 	}
-	leader->onGainSharedExperience(shareExperience, target);
+	const auto leaderStaminaBoost = static_cast<float>(leader->getStaminaXpBoost()) / 100;
+	leader->onGainSharedExperience(shareExperience * leaderStaminaBoost, target);
 }
 
 bool Party::canUseSharedExperience(const std::shared_ptr<Player> &player) {

src/creatures/players/grouping/party.hpp

@@ -40,6 +40,7 @@ class Party final : public SharedObject {
 	std::vector<std::shared_ptr<Player>> getInvitees();
 	size_t getMemberCount() const;
 	size_t getInvitationCount() const;
+	uint8_t getUniqueVocationsCount() const;
 
 	void disband();
 	bool invitePlayer(const std::shared_ptr<Player> &player);

src/lua/functions/creatures/player/party_functions.cpp

@@ -24,6 +24,7 @@ void PartyFunctions::init(lua_State* L) {
 	Lua::registerMethod(L, "Party", "getMemberCount", PartyFunctions::luaPartyGetMemberCount);
 	Lua::registerMethod(L, "Party", "getInvitees", PartyFunctions::luaPartyGetInvitees);
 	Lua::registerMethod(L, "Party", "getInviteeCount", PartyFunctions::luaPartyGetInviteeCount);
+	Lua::registerMethod(L, "Party", "getUniqueVocationsCount", PartyFunctions::luaPartyGetUniqueVocationsCount);
 	Lua::registerMethod(L, "Party", "addInvite", PartyFunctions::luaPartyAddInvite);
 	Lua::registerMethod(L, "Party", "removeInvite", PartyFunctions::luaPartyRemoveInvite);
 	Lua::registerMethod(L, "Party", "addMember", PartyFunctions::luaPartyAddMember);
@@ -162,6 +163,17 @@ int PartyFunctions::luaPartyGetInviteeCount(lua_State* L) {
 	return 1;
 }
 
+int PartyFunctions::luaPartyGetUniqueVocationsCount(lua_State* L) {
+	// party:getUniqueVocationsCount()
+	const auto &party = Lua::getUserdataShared<Party>(L, 1);
+	if (party) {
+		lua_pushnumber(L, party->getUniqueVocationsCount());
+	} else {
+		lua_pushnil(L);
+	}
+	return 1;
+}
+
 int PartyFunctions::luaPartyAddInvite(lua_State* L) {
 	// party:addInvite(player)
 	const auto &player = Lua::getPlayer(L, 2);

src/lua/functions/creatures/player/party_functions.hpp

@@ -22,6 +22,7 @@ class PartyFunctions {
 	static int luaPartyGetMemberCount(lua_State* L);
 	static int luaPartyGetInvitees(lua_State* L);
 	static int luaPartyGetInviteeCount(lua_State* L);
+	static int luaPartyGetUniqueVocationsCount(lua_State* L);
 	static int luaPartyAddInvite(lua_State* L);
 	static int luaPartyRemoveInvite(lua_State* L);
 	static int luaPartyAddMember(lua_State* L);