Condition

Multiple conditions can be set on an NPC which help the NPC determine what schedule should be run (handled in SelectSchedule() or variants).

An example of a condition is COND_LIGHT_DAMAGE which may cause the NPC to go to an alert state and select a schedule appropriate to this condition.

NPC's can implement their own custom conditions to deal with things unique to that NPC, for instance, you could use a COND_ON_FIRE to determine if the NPC is on fire and select specific schedules on this condition such as SCHED_JUMP_IN_WATER.

An interesting method is the GatherConditions() , it can be overridden in child classes to implement the selection of custom conditions, the method sets the NPC's conditions appropriate at the time based on game state.

The following condition has been taken from the headcrabs GatherConditions() method.

 if( m_lifeState == LIFE_ALIVE && GetWaterLevel() > 1 ) 
{ 
          // Start Drowning! 
         SetCondition( COND_HEADCRAB_IN_WATER ); 
} 

This if block checks to see if the headcrab is alive but submerged in water, if so a condition COND_HEADCRAB_IN_WATER is set.

Also another interesting method is the BuildScheduleTestBits(), it can be overridden to set custom condition to interrupt schedules. This is useful because you want to see your NPC react to the fire(COND_ON_FIREexample),start drowing(headcrab example) right now, not wait until the current schedule ends.

Here is code from the headcrabs BuildScheduleTestBits()

	if ( !IsCurSchedule(SCHED_HEADCRAB_DROWN) )
	{
		// Interrupt any schedule unless already drowning.
		SetCustomInterruptCondition( COND_HEADCRAB_IN_WATER );
	}
	else
	{
		// Don't stop drowning just because you're in water!
		ClearCustomInterruptCondition( COND_HEADCRAB_IN_WATER );
	}

If the condition COND_HEADCRAB_IN_WATER is set, it interrupts the current schedule unless it is already drowning. Then this is handled in SelectSchedule() to choose the appropriate schedule(SCHED_HEADCRAB_DROWN) that will end up drowning the headcrab.

Default Condition List

COND_NONE: A way for a function to return no condition to get

COND_IN_PVS

COND_IDLE_INTERRUPT: The schedule in question is a low priority idle and therefore a candidate for translation into something else

COND_LOW_PRIMARY_AMMO

COND_NO_PRIMARY_AMMO

COND_NO_SECONDARY_AMMO

COND_NO_WEAPON

COND_SEE_HATE

COND_SEE_FEAR

COND_SEE_DISLIKE

COND_SEE_ENEMY

COND_LOST_ENEMY

COND_ENEMY_OCCLUDED: Can't see m_hEnemy

COND_TARGET_OCCLUDED: Can't see m_hTargetEnt

COND_HAVE_ENEMY_LOS

COND_HAVE_TARGET_LOS

COND_LIGHT_DAMAGE

COND_HEAVY_DAMAGE

COND_PHYSICS_DAMAGE

COND_REPEATED_DAMAGE: Damaged several times in a row

COND_CAN_RANGE_ATTACK1: Hitscan weapon only

COND_CAN_RANGE_ATTACK2: Grenade weapon only

COND_CAN_MELEE_ATTACK1

COND_CAN_MELEE_ATTACK2

COND_PROVOKED

COND_NEW_ENEMY

COND_ENEMY_TOO_FAR

COND_ENEMY_FACING_ME

COND_BEHIND_ENEMY

COND_ENEMY_DEAD

COND_ENEMY_UNREACHABLE: Not connected to me via node graph

COND_SEE_PLAYER

COND_SEE_NEMESIS

COND_TASK_FAILED

COND_SCHEDULE_DONE

COND_SMELL

COND_TOO_CLOSE_TO_ATTACK

COND_TOO_FAR_TO_ATTACK

COND_NOT_FACING_ATTACK

COND_WEAPON_HAS_LOS

COND_WEAPON_BLOCKED_BY_FRIEND: Friend between weapon and target

COND_WEAPON_PLAYER_IN_SPREAD: Player in shooting direction

COND_WEAPON_PLAYER_NEAR_TARGET: Player near shooting position

COND_WEAPON_SIGHT_OCCLUDED

COND_BETTER_WEAPON_AVAILABLE

COND_HEALTH_ITEM_AVAILABLE: There's a healthkit available.

COND_GIVE_WAY: Another npc requested that I give way

COND_WAY_CLEAR: I no longer have to give way

COND_HEAR_DANGER

COND_HEAR_THUMPER

COND_HEAR_BUGBAIT

COND_HEAR_COMBAT

COND_HEAR_WORLD

COND_HEAR_PLAYER

COND_HEAR_BULLET_IMPACT

COND_HEAR_PHYSICS_DANGER

COND_HEAR_MOVE_AWAY

COND_NO_HEAR_DANGER: Since we can't use CONDITION. Mutually exclusive with COND_HEAR_DANGER

COND_FLOATING_OFF_GROUND

COND_RECEIVED_ORDERS

COND_PLAYER_ADDED_TO_SQUAD

COND_PLAYER_REMOVED_FROM_SQUAD

COND_PLAYER_PUSHING

COND_NPC_FREEZE: We received an npc_freeze command while we were unfrozen

COND_NPC_UNFREEZE: We received an npc_freeze command while we were frozen

COND_TALKER_RESPOND_TO_QUESTION