[Experience] Add exp mod to npc types to let a server op change the exp modifier (#1252)

* Add exp mod to npc types to let a server op change the exp modifier a npc gives (useful for custom content)

* Updated version.h

common/version.h

@@ -34,7 +34,7 @@
  * Manifest: https://github.com/EQEmu/Server/blob/master/utils/sql/db_update_manifest.txt
  */
 
-#define CURRENT_BINARY_DATABASE_VERSION 9159
+#define CURRENT_BINARY_DATABASE_VERSION 9160
 
 #ifdef BOTS
 	#define CURRENT_BINARY_BOTS_DATABASE_VERSION 9027

utils/sql/db_update_manifest.txt

@@ -413,6 +413,7 @@
 9157|2020_09_02_pet_taunting.sql|SHOW COLUMNS from `character_pet_info` LIKE 'taunting'|empty|
 9158|2020_12_09_underworld.sql|SHOW COLUMNS from `zone` LIKE 'underworld_teleport_index'|empty|
 9159|2020_12_22_expedition_system.sql|SELECT * FROM db_version WHERE version >= 9159|empty|
+9160|2021_02_14_npc_exp_mod.sql|SHOW COLUMNS from `npc_types` LIKE 'exp_mod'|empty|
 
 # Upgrade conditions:
 # 	This won't be needed after this system is implemented, but it is used database that are not

utils/sql/git/required/2021_02_14_npc_exp_mod.sql

@@ -0,0 +1 @@
+ALTER TABLE `npc_types` ADD COLUMN `exp_mod` INT NOT NULL DEFAULT '100' AFTER `always_aggro`;

zone/exp.cpp

@@ -215,7 +215,15 @@ uint32 Client::GetExperienceForKill(Mob *against)
 
 	if (against && against->IsNPC()) {
 		uint32 level = (uint32)against->GetLevel();
-		return EXP_FORMULA;
+		uint32 ret = EXP_FORMULA;
+
+		auto mod = against->GetKillExpMod();
+		if(mod >= 0) {
+			ret *= mod;
+			ret /= 100;
+		}
+
+		return ret;
 	}
 
 	return 0;

zone/mob.h

@@ -695,6 +695,7 @@ public:
 	bool PlotPositionOnArcInFrontOfTarget(Mob *target, float &x_dest, float &y_dest, float &z_dest, float distance, float min_deg = 5.0f, float max_deg = 150.0f);
 	bool PlotPositionOnArcBehindTarget(Mob *target, float &x_dest, float &y_dest, float &z_dest, float distance);
 	bool PlotPositionBehindMeFacingTarget(Mob *target, float &x_dest, float &y_dest, float &z_dest, float min_dist = 1.0f, float max_dist = 5.0f);
+	virtual int GetKillExpMod() const { return 100; }
 
 	// aura functions
 	void MakeAura(uint16 spell_id);

zone/npc.h

@@ -422,10 +422,12 @@ public:
 	void SetCombatEvent(bool b) { combat_event = b; }
 
 	/* Only allows players that killed corpse to loot */
-	const bool HasPrivateCorpse() const { return NPCTypedata->private_corpse; }
+	const bool HasPrivateCorpse() const { return NPCTypedata_ours ? NPCTypedata_ours->private_corpse : NPCTypedata->private_corpse; }
 
-	virtual const bool IsUnderwaterOnly() const { return NPCTypedata->underwater; }
+	virtual const bool IsUnderwaterOnly() const { return NPCTypedata_ours ? NPCTypedata_ours->underwater : NPCTypedata->underwater; }
-	const char* GetRawNPCTypeName() const { return NPCTypedata->name; }
+	const char* GetRawNPCTypeName() const { return NPCTypedata_ours ? NPCTypedata_ours->name : NPCTypedata->name; }
+
+	virtual int GetKillExpMod() const { return NPCTypedata_ours ? NPCTypedata_ours->exp_mod : NPCTypedata->exp_mod; }
 
 	void ChangeLastName(const char* in_lastname);
 	void ClearLastName();

zone/zonedb.cpp

@@ -2525,7 +2525,8 @@ const NPCType *ZoneDatabase::LoadNPCTypesData(uint32 npc_type_id, bool bulk_load
 		"npc_types.stuck_behavior, "
 		"npc_types.model, "
 		"npc_types.flymode, "
-		"npc_types.always_aggro "
+		"npc_types.always_aggro, "
+		"npc_types.exp_mod "
 		"FROM npc_types %s",
 		where_condition.c_str()
 	);
@@ -2728,6 +2729,7 @@ const NPCType *ZoneDatabase::LoadNPCTypesData(uint32 npc_type_id, bool bulk_load
 		temp_npctype_data->use_model        	= atoi(row[110]);
 		temp_npctype_data->flymode          	= atoi(row[111]);
 		temp_npctype_data->always_aggro	        = atoi(row[112]);
+		temp_npctype_data->exp_mod              = atoi(row[113]);
 
 		temp_npctype_data->skip_auto_scale = false; // hardcoded here for now
 

zone/zonedump.h

@@ -148,6 +148,7 @@ struct NPCType
 	uint16	use_model;
 	int8	flymode;
 	bool	always_aggro;
+	int     exp_mod;
 };
 
 namespace player_lootitem {