Core/Misc: Add functionality to allow low level quests/kills/discoveries to grant experience

Port From (https://github.com/TrinityCore/TrinityCore/commit/502f77fe8cb082843f7eb385159dd5038a059443)

Source/Framework/Constants/SharedConst.cs

@@ -1497,11 +1497,14 @@ namespace Framework.Constants
         MaxResultsLookupCommands,
         MaxWho,
         MinCharterName,
+        MinCreatureScaledXpRatio,
+        MinDiscoveredScaledXpRatio,
         MinDualspecLevel,
         MinLevelStatSave,
         MinPetName,
         MinPetitionSigns,
         MinPlayerName,
+        MinQuestScaledXpRatio,
         NoGrayAggroAbove,
         NoGrayAggroBelow,
         NoResetTalentCost,

Source/Game/Entities/Player/Player.cs

@@ -5007,7 +5007,7 @@ namespace Game.Entities
             uint k_grey = Formulas.GetGrayLevel(GetLevel());
 
             // Victim level less gray level
-            if (v_level < k_grey)
+            if (v_level < k_grey && WorldConfig.GetIntValue(WorldCfg.MinCreatureScaledXpRatio) == 0)
                 return false;
 
             Creature creature = victim.ToCreature();
@@ -6172,6 +6172,12 @@ namespace Game.Entities
                             XP = (uint)(Global.ObjectMgr.GetBaseXP(areaLevel) * WorldConfig.GetFloatValue(WorldCfg.RateXpExplore));
                         }
 
+                        if (WorldConfig.GetIntValue(WorldCfg.MinDiscoveredScaledXpRatio) != 0)
+                        {
+                            uint minScaledXP = (uint)(Global.ObjectMgr.GetBaseXP(areaLevel) * WorldConfig.GetFloatValue(WorldCfg.RateXpExplore)) * WorldConfig.GetUIntValue(WorldCfg.MinDiscoveredScaledXpRatio) / 100;
+                            XP = Math.Max(minScaledXP, XP);
+                        }
+
                         GiveXP(XP, null);
                         SendExplorationExperience(areaId, XP);
                     }

Source/Game/Miscellaneous/Formulas.cs

@@ -136,6 +136,13 @@ namespace Game
                     baseGain = 0;
             }
 
+            if (WorldConfig.GetIntValue(WorldCfg.MinCreatureScaledXpRatio) != 0 && pl_level != mob_level)
+            {
+                // Use mob level instead of player level to avoid overscaling on gain in a min is enforced
+                uint baseGainMin = BaseGain(pl_level, pl_level) * WorldConfig.GetUIntValue(WorldCfg.MinCreatureScaledXpRatio) / 100;
+                baseGain = Math.Max(baseGainMin, baseGain);
+            }
+
             Global.ScriptMgr.OnBaseGainCalculation(baseGain, pl_level, mob_level);
             return baseGain;
         }

Source/Game/Quest/Quest.cs

@@ -294,14 +294,13 @@ namespace Game
                 if (player.GetLevel() >= Global.ObjectMgr.GetMaxLevelForExpansion(PlayerConst.CurrentExpansion - 1) && player.GetSession().GetExpansion() == PlayerConst.CurrentExpansion && Expansion < (int)PlayerConst.CurrentExpansion)
                     xp = (uint)(xp / 9.0f);
 
-                if (xp <= 100)
-                    xp = 5 * ((xp + 2) / 5);
-                else if (xp <= 500)
-                    xp = 10 * ((xp + 5) / 10);
-                else if (xp <= 1000)
-                    xp = 25 * ((xp + 12) / 25);
-                else
-                    xp = 50 * ((xp + 25) / 50);
+                xp = RoundXPValue(xp);
+
+                if (WorldConfig.GetUIntValue(WorldCfg.MinQuestScaledXpRatio) != 0)
+                {
+                    uint minScaledXP = RoundXPValue((uint)(questXp.Difficulty[RewardXPDifficulty] * RewardXPMultiplier)) * WorldConfig.GetUIntValue(WorldCfg.MinQuestScaledXpRatio) / 100;
+                    xp = Math.Max(minScaledXP, xp);
+                }
 
                 return xp;
             }
@@ -558,6 +557,18 @@ namespace Game
             QueryData.Info.TimeAllowed = LimitTime;
         }
 
+        public static uint RoundXPValue(uint xp)
+        {
+            if (xp <= 100)
+                return 5 * ((xp + 2) / 5);
+            else if (xp <= 500)
+                return 10 * ((xp + 5) / 10);
+            else if (xp <= 1000)
+                return 25 * ((xp + 12) / 25);
+            else
+                return 50 * ((xp + 25) / 50);
+        }
+
         public bool HasFlag(QuestFlags flag) { return (Flags & flag) != 0; }
         public bool HasFlagEx(QuestFlagsEx flag) { return (FlagsEx & flag) != 0; }
         public bool HasFlagEx(QuestFlagsEx2 flag) { return (FlagsEx2 & flag) != 0; }

Source/Game/Server/WorldConfig.cs

@@ -295,6 +295,28 @@ namespace Game
 
             Values[WorldCfg.GroupXpDistance] = GetDefaultValue("MaxGroupXPDistance", 74.0f);
             Values[WorldCfg.MaxRecruitAFriendDistance] = GetDefaultValue("MaxRecruitAFriendBonusDistance", 100.0f);
+            Values[WorldCfg.MinQuestScaledXpRatio] = GetDefaultValue("MinQuestScaledXPRatio", 0);
+            if ((int)Values[WorldCfg.MinQuestScaledXpRatio] > 100)
+            {
+                Log.outError(LogFilter.ServerLoading, $"MinQuestScaledXPRatio ({Values[WorldCfg.MinQuestScaledXpRatio]}) must be in range 0..100. Set to 0.");
+                Values[WorldCfg.MinQuestScaledXpRatio] = 0;
+            }
+
+            Values[WorldCfg.MinCreatureScaledXpRatio] = GetDefaultValue("MinCreatureScaledXPRatio", 0);
+            if ((int)Values[WorldCfg.MinCreatureScaledXpRatio] > 100)
+            {
+                Log.outError(LogFilter.ServerLoading, $"MinCreatureScaledXPRatio ({Values[WorldCfg.MinCreatureScaledXpRatio]}) must be in range 0..100. Set to 0.");
+                Values[WorldCfg.MinCreatureScaledXpRatio] = 0;
+            }
+
+            Values[WorldCfg.MinDiscoveredScaledXpRatio] = GetDefaultValue("MinDiscoveredScaledXPRatio", 0);
+            if ((int)Values[WorldCfg.MinDiscoveredScaledXpRatio] > 100)
+            {
+                Log.outError(LogFilter.ServerLoading, $"MinDiscoveredScaledXPRatio ({Values[WorldCfg.MinDiscoveredScaledXpRatio]}) must be in range 0..100. Set to 0.");
+                Values[WorldCfg.MinDiscoveredScaledXpRatio] = 0;
+            }
+
+            /// @todo Add MonsterSight (with meaning) in worldserver.conf or put them as define
             Values[WorldCfg.SightMonster] = GetDefaultValue("MonsterSight", 50.0f);
 
             if (reload)

Source/WorldServer/WorldServer.conf.dist

@@ -1104,6 +1104,34 @@ MaxGroupXPDistance = 74
 
 MaxRecruitAFriendBonusDistance = 100
 
+#
+#    MinQuestScaledXPRatio
+#        Description: Min ratio of experience that a quest can grant when player level scaling is factored.
+#        Example:     50 (No less than 50% experience granted from a lower leveled quests completion)
+#                     100 (Quests always grant full experience upon completion)
+#        Default:     0 - (Quests too low may grant no experience)
+
+MinQuestScaledXPRatio = 0
+
+#
+#    MinCreatureScaledXPRatio
+#        Description: Min ratio of experience that a creature kill can grant when player level scaling is factored.  This 
+#                     will also allow spell procs to trigger, such as Drain Soul, if > 0 and exp is grantable.
+#        Example:     50 (No less than 50% experience granted from a lower leveled creature kill)
+#                     100 (Creature kills always grant full experience upon kill)
+#        Default:     0 - (Creatures too low may grant no experience)
+
+MinCreatureScaledXPRatio = 0
+
+#
+#    MinDiscoveredScaledXPRatio
+#        Description: Min ratio of experience that an area discovery event will grant when player level scaling is factored.
+#        Example:     50 (No less than 50% experience granted from discovering a new section of map)
+#                     100 (Map exploration always grant full experience upon discovery)
+#        Default:     0 - (No experience granted when discovered area is too low level)
+
+MinDiscoveredScaledXPRatio = 0
+
 #
 #    MailDeliveryDelay
 #        Description: Time (in seconds) mail delivery is delayed when sending items.