Synchronize Damage Feature (rathena#8305)

- Added a new monster stat "ClientAttackMotion" to mob_db.yml which is the time from when a monster attacks until which the damage shows on the client at 1x speed
- Added a new config synchronize_damage; when set to "yes", the client will display the damage of normal monster attacks at the exact time it is applied on the server, removing position lag (fixes rathena#259)

Special thanks to all people who worked together to make this possible.

Co-authored-by: aleos, Lemongrass3110, Atemo

conf/battle/battle.conf

@@ -130,10 +130,19 @@ equip_self_break_rate: 100
 // This affects the behaviour of skills like acid terror and meltdown
 equip_skill_break_rate: 100
 
-// Do weapon attacks have a attack speed delay before actual damage is applied? (Note 1)
-// NOTE: The official setting is yes, even thought it degrades performance a bit.
+// Should damage have a delay before it is applied? (Note 1)
+// Some skills might not have a delay by default regardless of this setting.
+// The official setting is yes, even thought it degrades performance a bit.
 delay_battle_damage: yes
 
+// Should the damage timing be synchronized between the client and server? (Note 1)
+// This is not official behavior, but it should remove the position lag after being hit by a monster.
+// This setting only affects normal monster attacks and takes priority over "delay_battle_damage".
+// Many skills show their damage immediately, so setting "delay_battle_damage" to "no" at the same
+// time might improve the experience further, but will not work for all skills.
+// Tired of Dark Illusion hitting you 5 seconds too late? Then turn this on.
+synchronize_damage: no
+
 // Are arrows/ammo consumed when used on a bow/gun?
 // 0 = No
 // 1 = Yes

db/import-tmpl/mob_db.yml

@@ -56,6 +56,7 @@
 #   WalkSpeed               Walk speed. (Default: DEFAULT_WALK_SPEED)
 #   AttackDelay             Attack speed. (Default: 0)
 #   AttackMotion            Attack animation speed. (Default: 0)
+#   ClientAttackMotion      Client attack speed. (Default: AttackMotion)
 #   DamageMotion            Damage animation speed. (Default: 0)
 #   DamageTaken             Rate at which the monster will receive incoming damage. (Default: 100)
 #   Ai                      Aegis monster type AI behavior. (Default: 06)
@@ -77,7 +78,7 @@
 
 Header:
   Type: MOB_DB
-  Version: 3
+  Version: 4
 
 #Body:
 # eAthena Dev Team

db/mob_db.yml

@@ -56,6 +56,7 @@
 #   WalkSpeed               Walk speed. (Default: DEFAULT_WALK_SPEED)
 #   AttackDelay             Attack speed. (Default: 0)
 #   AttackMotion            Attack animation speed. (Default: 0)
+#   ClientAttackMotion      Client attack speed. (Default: AttackMotion)
 #   DamageMotion            Damage animation speed. (Default: 0)
 #   DamageTaken             Rate at which the monster will receive incoming damage. (Default: 100)
 #   Ai                      Aegis monster type AI behavior. (Default: 06)
@@ -77,7 +78,7 @@
 
 Header:
   Type: MOB_DB
-  Version: 3
+  Version: 4
 
 Footer:
   Imports: