Trigger once

GoldSrc

Source Engine

edit

Class hierarchy
CTriggerOnce ↳CTriggerMultiple ↳CBaseTrigger ↳CBaseToggle ↳CBaseEntity
triggers.cpp

trigger_once is a brush entity available in all Source games. It is a trigger volume that removes itself after it has been triggered (touched by a qualifying entity) once. A trigger uses outputs to activate an event in another entity.

Keyvalues

Name (targetname) <string>[ Edit ]

The name that other entities refer to this entity by, via Inputs/Outputs or other keyvalues (e.g. parentname or target).
Also displayed in Hammer's 2D views and Entity Report.

See also:  Generic Keyvalues, Inputs and Outputs available to all entities

BaseTrigger

Filter Name (filtername) <filter> A filter entity to test potential activators against. Start Disabled (StartDisabled) <boolean> Stay dormant until activated (with theEnableinput).

Flags

BaseTrigger

Everything (not including physics debris) : [64] Clients (Survivors, Special Infected, Tanks ) : [1] Only clients in vehicles : [32] Only clients *not* in vehicles : [512] Disallow Bots (removed since ) : [4096] NPCs (Common Infected, Witches ) : [2] Only player ally NPCs : [16] Only NPCs in vehicles (respects player ally flag) : [2048] Physics Objects (not including physics debris) : [8] Physics debris (include also physics debris) : [1024] Pushables (Passes entities with classname func_pushable) : [4]  Deprecated. Equivalent to using Everything + filter_activator_class that filters func_pushable.

Inputs

Toggle

Toggles this trigger between enabled and disabled states.

Enable

Enable trigger

Disable

Disable trigger

StartTouch  (in all games since ) !FGD

Behave as if the !caller entity had just entered the trigger volume. Accepts non-physical entities.

Note:Will trigger OnStartTouch output and the trigger won't be removed.

Warning:If !caller doesn't exist game will crash

Outputs

OnStartTouch

OnTrigger

!activator = entity that touched the trigger
!caller = this entity
Fired when an entity starts touching this trigger. The touching entity must pass this trigger's filters to cause this output to fire.

Important:If the trigger_once is enabled while multiple entities that can trigger it are touching it each output will have different outcomes. OnStartTouch will fire for each !activator. Meanwhile OnTrigger will only trigger once.

Note: The refire amount will decide how many times your OnStartTouch will fire.

See also

• trigger_multiple
• Inputs and Outputs