[Bug Fix] Accuracy, Avoidance and Atk adjustments (#4336)

* [Bug Fix] Accuracy, Avoidance and Atk adjustments

- Applied Fix to Attack Power contributing too much to damage.
   Rule of thumb for era was 100 attack = 10% damage increase, but I was seeing closer to 15-25%.  Found that in the GetATK() function it seemed to be double counting attack power from items and spells, so I applied a /2 to remedy this.

* Update Tune

common/ruletypes.h

@@ -606,6 +606,8 @@ RULE_BOOL(Combat, BashTwoHanderUseShoulderAC, false, "Enable to use shoulder AC
 RULE_REAL(Combat, BashACBonusDivisor, 25.0, "this divides the AC value contribution to bash damage, lower to increase damage")
 RULE_BOOL(Combat, UseMobStaticOffenseSkill, false, "Toggle to enabled the use of a static offense skill for Mobs.  DEFAULT: false")
 RULE_BOOL(Combat, UseEnhancedMobStaticWeaponSkill, false, "Toggle to enabled the use of an enhanced (slightly higher hit rate) static weapon skill for Mobs.  DEFAULT: false")
+RULE_INT(Combat, PCAttackPowerScaling, 100, "Applies scaling to PC Attack Power (75 = 75%).  DEFAULT: 100 to not adjust existing Servers")
+RULE_INT(Combat, PCAccuracyAvoidanceMod2Scale, 100, "Scale Factor for PC Accuracy and Avoidance (Mod2, found on items).  Found a value of 100 to make both too strong (75 = x0.75).  DEFAULT: 100 to not adjust existing Servers")
 RULE_CATEGORY_END()
 
 RULE_CATEGORY(NPC)

zone/attack.cpp

@@ -194,8 +194,15 @@ int Mob::GetTotalToHit(EQ::skills::SkillType skill, int chance_mod)
 	// unsure on the stacking order of these effects, rather hard to parse
 	// item mod2 accuracy isn't applied to range? Theory crafting and parses back it up I guess
 	// mod2 accuracy -- flat bonus
-	if (skill != EQ::skills::SkillArchery && skill != EQ::skills::SkillThrowing)
+	if (skill != EQ::skills::SkillArchery && skill != EQ::skills::SkillThrowing) {
 		accuracy += itembonuses.HitChance;
+	} else {
+		// Applying a scale factor as sources suggest Accuracy should reduce number of missing by 0.1% per point, so 150 = 15% reduction in misses.
+		// Based on my calculator 150 Accuracy was reducing misses by too much (closer to 20%)
+		// NOTE: This doesn't mean if you have a 30% miss chance you now miss 15%.  It means if you have a 30% miss chance you now have a 30% * (100% - 15%) = 30% * 85% = 25.5% miss chance
+		// Using same scale factor for Avoidance and Accuracy since they impact the formula about the same.
+		accuracy += itembonuses.HitChance * RuleI(Combat, PCAccuracyAvoidanceMod2Scale) / 100;
+	}
 
 	//518 Increase ATK accuracy by percentage, stackable
 	auto atkhit_bonus = itembonuses.Attack_Accuracy_Max_Percent + aabonuses.Attack_Accuracy_Max_Percent + spellbonuses.Attack_Accuracy_Max_Percent;
@@ -987,10 +994,20 @@ int Mob::offense(EQ::skills::SkillType skill)
 			break;
 	}
 
-	if (stat_bonus >= 75)
+	if (stat_bonus >= 75) {
 		offense += (2 * stat_bonus - 150) / 3;
+	}
+
+	// GetATK() = ATK + itembonuses.ATK + spellbonuses.ATK.  However, ATK appears to already be itembonuses.ATK + spellbonuses.ATK for PCs, so as is, it is double counting attack
+	// This causes attack to be significantly more important than it should be based on era rule of thumbs.  I do not want to change the GetATK() function in case doing so breaks something,
+	// so instead I am just adding a /2 to remedy the double counting.  NPCs do not have this issue, so they are broken up.
+	// PCAttackPowerScaling is used to help bring attack power further in line with era estimates.
+	if (IsOfClientBotMerc()) {
+		offense += (GetATK() / 2 + GetPetATKBonusFromOwner()) * RuleI(Combat, PCAttackPowerScaling) / 100;
+	} else {
+		offense += GetATK();
+	}
 
-	offense += GetATK() + GetPetATKBonusFromOwner();
 	return offense;
 }
 

zone/tune.cpp

@@ -1124,17 +1124,28 @@ int64 Mob::Tuneoffense(EQ::skills::SkillType skill, int atk_override, int add_at
 		break;
 	}
 
-	if (stat_bonus >= 75)
+	if (stat_bonus >= 75) {
 		offense += (2 * stat_bonus - 150) / 3;
+	}
 
 	int32 tune_atk = GetATK();
+
+	// GetATK() = ATK + itembonuses.ATK + spellbonuses.ATK.  However, ATK appears to already be itembonuses.ATK + spellbonuses.ATK for PCs, so as is, it is double counting attack
+	// This causes attack to be significantly more important than it should be based on era rule of thumbs.  I do not want to change the GetATK() function in case doing so breaks something,
+	// so instead I am just adding a /2 to remedy the double counting.  NPCs do not have this issue, so they are broken up.
+	// PCAttackPowerScaling is used to help bring attack power further in line with era estimates.
+	if (IsOfClientBotMerc()) {
+		offense += (GetATK() / 2 + GetPetATKBonusFromOwner()) * RuleI(Combat, PCAttackPowerScaling) / 100;
+	} else {
+		offense += GetATK();
+	}
+
 	if (atk_override) {
 		tune_atk = atk_override;
 	}
 
 	tune_atk += add_atk;
 
-	offense += tune_atk + GetPetATKBonusFromOwner();
 	return offense;
 }
 
@@ -1267,8 +1278,15 @@ int64 Mob::TuneGetTotalToHit(EQ::skills::SkillType skill, int chance_mod, int ac
 	// unsure on the stacking order of these effects, rather hard to parse
 	// item mod2 accuracy isn't applied to range? Theory crafting and parses back it up I guess
 	// mod2 accuracy -- flat bonus
-	if (skill != EQ::skills::SkillArchery && skill != EQ::skills::SkillThrowing)
+	if (skill != EQ::skills::SkillArchery && skill != EQ::skills::SkillThrowing) {
 		accuracy += itembonuses.HitChance;
+	} else {
+		// Applying a scale factor as sources suggest Accuracy should reduce number of missing by 0.1% per point, so 150 = 15% reduction in misses.
+		// Based on my calculator 150 Accuracy was reducing misses by too much (closer to 20%)
+		// NOTE: This doesn't mean if you have a 30% miss chance you now miss 15%.  It means if you have a 30% miss chance you now have a 30% * (100% - 15%) = 30% * 85% = 25.5% miss chance
+		// Using same scale factor for Avoidance and Accuracy since they impact the formula about the same.
+		accuracy += itembonuses.HitChance * RuleI(Combat, PCAccuracyAvoidanceMod2Scale) / 100;
+	}
 
 	//518 Increase ATK accuracy by percentage, stackable
 	auto atkhit_bonus = itembonuses.Attack_Accuracy_Max_Percent + aabonuses.Attack_Accuracy_Max_Percent + spellbonuses.Attack_Accuracy_Max_Percent;