TF2's player damage process

note: documentation is released as-is and reports of any inaccuracies will be ignored

Call tree:

• CTFPlayer::ModifyDamageInfo
• CTFPlayer::OnTakeDamage
  • If attacker is carrying RUNE_STRENGTH, scale damage by 2.0f.
  • CTFGameRules::ApplyOnDamageModifyRules
    • CTFWeaponBase::ApplyOnHitAttributes
  • If phasing: CTFPlayer::ApplyPushFromDamage
  • Otherwise: CBaseCombatCharacter::OnTakeDamage (bypasses override on CBasePlayer)
    • If lifestate is alive: CTFPlayer::OnTakeDamage_Alive
      • CTFGameRules::ApplyOnDamageAliveModifyRules
      • CTFPlayer::ApplyPushFromDamage
  • CTFWeaponBase::ApplyOnInjuredAttributes on victim's weapon
  • CTFWeaponBase::ApplyPostHitEffects on attacker's weapon
  • CTFPlayer::OnDealtDamage on attacker

Function information

CTFPlayer::ModifyDamageInfo

• Called before damage is applied.
• Only used for scaling damage against sentry targets (8185700)

CTFGameRules::ApplyOnDamageModifyRules

• Applies minicrit / critical alterations.
• Applies distance rampup / falloff modifiers.
• Applies (mini)crit damage modifiers.

CTFGameRules::ApplyOnDamageAliveModifyRules

• The return value controls the actual damage taken. This allows for modifying the result independently of any damage forces.
• However, Mad Milk effects still perform healing based on the original damage.
  • It sounds like you should be able to preserve the damage force by using m_flDamageForForce, but it doesn't appear to work in practice.
• A return value of -1.0f indicates a "hard out", which bypasses additional damage effects in CTFPlayer::OnTakeDamage_Alive.

CTFWeaponBase::ApplyOnHitAttributes

• This does not get called if the target is invulnerable. Target may be a non-player entity.
• Attribute classes that are applied here:
  • add_onhit_addammo
  • extra_damage_on_hit
  • (Attributes past this point are only applied to player enemies and halloween bosses.)
  • reveal_cloaked_victim_on_hit
  • reveal_disguised_victim_on_hit
  • (Attributes past this point are not applied if the target is disguised or from burn damage.)
  • add_onhit_addhealth
  • charge_meter_on_hit
  • speed_boost_on_hit
  • add_onhit_ubercharge
  • rage_on_hit
  • boost_on_damage
  • aoe_heal_chance
  • crits_on_damage
  • stun_on_damage
  • aoe_blast_on_damage
  • generate_rage_on_dmg
  • mult_onhit_enemyspeed
  • mult_onhit_enemyspeed_major
  • mark_for_death
  • stun_waist_high_airborne

CTFWeaponBase::ApplyOnInjuredAttributes

• Called on a victim's active weapon; damage must be applied by a player.
• Currently used for the following attribute classes:
  • melts_in_fire (only applicable to Knife-based items)
  • become_fireproof_on_hit_by_fire (applicable to all weapons)

CTFWeaponBase::ApplyPostHitEffects

• Called on an attacker's weapon when damage has been applied to another player.
• Used for the following attribute classes:
  • scattergun_knockback_mult (only applicable to Scatterguns with the ability to inflict knockback)
  • For all weapons:
    • subtract_victim_medigun_charge_onhit
    • subtract_victim_cloak_on_hit

CTFPlayer::OnDealtDamage

• Called on the attacker when damage was applied. Victim can be any entity; not just players.
• This is only used for DPS statistics tracking.