npc_turret_ground

Combine ground turret

npc_turret_ground is a point entity available in Half-Life 2, Half-Life 2: Episode One, Half-Life 2: Episode Two, and Half-Life 2: Deathmatch. It creates a Combine ground turret.

Note:In the Nexus building (the d3_c17_10b map) these were seen entrenched within the floor, and could only be killed by blast damage, like lobbing a hand grenade inside its lift. That lift, and the ability to destroy the turret, is not part of this entity. (The lift was a func_door brush rig, and the player really killed an invisible npc_bullseye, filtered to be killed by blast damage only by a filter_damage_type, that signalled the turret to descend and lock.

Note:This entity may be neutral to the player by default! In such cases, an ai_relationship will be required.

Important:This entity operates in a very particular way. On spawn, it remembers its origin position as the "closed" position. It considers itself "closed" unless its Z coordinate is more than 1 unit away from that remembered position. If it is "closed", it will not produce the scanning beam effect and sounds (but will still attack things it hates).
As such, to make it work the same way as in Half-Life 2, it must be parented to another entity that can move up and down, and thus be moved up or down for more than 1 unit of distance. Once it moves, it'll start scanning. The Enable input will then make the turret fully active.

Bug:Rotating the turret after it activated causes the laser effect to dislocate from the gun.

Note:Some keyvalues, spawnflags, effect flags, inputs, or outputs might not affect an NPC, based on the functionality and coding of the NPC.

Keyvalues

BaseNPC keyvalues Expand

CBaseCombatCharacter: Relationship (Relationship) <string> !FGD <string|targetname or classname> <string|disposition> <int|rank> Changes whether this entity likes or dislikes certain other things. Used like the ai_relationship entity, with this entity as the subject. Values for disposition are: D_HT: Hate D_FR: Fear D_LI: Like D_NU: Neutral Physics Impact Damage Scale (physdamagescale) <float> Multiplier for damage amount when this entity is hit by a physics object. With a value of 0 the entity will take no damage from physics. CAI_BaseNPC: Target Path Corner (target) <targetname> The path_corner that this NPC will move to after spawning. Squad Name (squadname) <string> NPCs that are in the same squad (i.e., have matching squad names) will share information about enemies and will take turns attacking and covering each other. Hint Group (hintgroup) <string> Hint groups are used by NPCs to restrict their hint-node searching to a subset of the map's hint nodes. Only hint nodes with matching hint group names will be considered by this NPC. Hint Limit Nav (hintlimiting) <boolean> Limits NPC to using specified hint group for navigation requests. Does not limit local navigation. Sleep State (sleepstate) <choices> Holds the NPC in stasis until specified condition. See also Wake Radius and Wake Squad. 0: None 1: Waiting for threat 2: Waiting for PVS 3: Waiting for input, ignore PVS 4: Auto PVS 5: Auto PVS after PVS Wake Radius (wakeradius) <float> Auto-wake if player comes within this distance. Wake Squad (wakesquad) <boolean> Wake all of the NPCs squadmates if the NPC is woken. Enemy Filter (enemyfilter) <targetname> Filter entity to test targets against. Ignore unseen enemies (ignoreunseenenemies) <boolean> Prefers visible enemies, regardless of distance or relationship priority. DamageFilter: Damage Filter (damagefilter) <targetname> Name of the filter_damage_type entity that controls which entities can damage us.

Parentname:

Parent (parentname) <targetname>

Specifies a movement parent. An entity will maintain its initial offset from its parent. An attachment point can be added to the end of the name, separated by a comma.

Flags

ExpandBaseNPC flags 

Wait Till Seen : [1]

Prevents this NPC from seeing (or being seen) until it enters a player's viewcone.

Gag : [2]

Won't make IDLE sounds until it's angry.

Fall to ground (unchecked means teleport to ground) : [4]

Drop Healthkit : [8]

Causes this NPC to drop an item_healthvial upon dying.

Efficient : [16]

Don't acquire enemies or avoid obstacles

Wait For Script : [128]

Forces this NPC to "wait" in an idle state until it finishes playing a scripted_sequence.

Long Visibility/Shoot : [256]

By default, increases a NPC's sight range to 6,000 units and allows it to attack from anywhere within that distance.

Fade Corpse : [512]

Think outside PVS : [1024]

Allows this NPC to run its regular AI outside of any player's PVS.

Template NPC : [2048]

Marks this NPC as a template for entities like npc_template_maker. The NPC will not spawn on its own. This is not needed for point_template.

Do Alternate collision for this NPC (player avoidance) : [4096]

Note:This flag is disabled in episodic for player companions, because the StartScripting input does this.

Don't drop weapons : [8192]

Ignore player push : [16384] (in all games since )

Entity won't give way to player.

Inputs

ExpandBaseNPC inputs 

CAI_BaseNPC:

ActivateSpeedModifier  !FGD

DisableSpeedModifier  !FGD

Break

Smash into pieces. If this is not possible, disappear.

BecomeRagdoll  (in all games since )

Remove itself and instantly become a ragdoll with zero force (just go limp). OnDeath, etc. outputs will NOT be fired.

ForceInteractionWithNPC <string> <string>  (in all games since )

Force the NPC to use a dynamic interaction with another NPC. Syntax is <targetname> <dynamic interaction>.

ForgetEntity <targetname>

Clears out the NPC's knowledge of a named entity.

UpdateEnemyMemory  (in all games since )

Update (or create) this NPC's memory of of the given entity.

GagEnable

GagDisable

Gagged NPCs won't speak (or moan, caw, etc.) unless made to be a choreographed scene.

HolsterWeapon  (in all games since )

UnholsterWeapon  (in all games since )

Force the NPC to holster or unholster their weapon. Ignored if the NPC is scripting or if the NPC doesn't use weapons.

HolsterAndDestroyWeapon  (in all games since )

Same as HolsterWeapon, except the weapon is destroyed once it has been concealed.

IgnoreDangerSounds <float>

Ignore danger sounds for the specified number of seconds.

InsideTransition  !FGD

OutsideTransition  !FGD

SetBodyGroup <integer>

HACK: Sets this NPC's body group (from 0–n).

SetEnemyFilter <string>

SetHealth <integer>

Set the NPC's health.

SetMaxLookDistance <float> (only in )

Sets the maximum look distance for the NPC. Defaults are 2048 and 6000 for long range NPCs.

SetRelationship <string|targetname or classname> <string|disposition> <int|rank>

Changes whether this NPC likes or dislikes certain others. Used like the ai_relationship entity, with this NPC as the subject.

Values for disposition are:

• D_HT: Hate
• D_FR: Fear
• D_LI: Like
• D_NU: Neutral

SetSquad <string>

Change the name of this NPC's squad. Leaving the parameter blank will remove the NPC from any existing squad.

StartScripting

StopScripting

Enter/exit scripting state, where NPCs ignore a variety of stimulus that would make them break out of their scripts. They ignore danger sounds, ignore +Use, don't idle speak or respond to other NPCs' idle speech, and so on.

Wake

Wakes up the NPC if it is sleeping.

CBaseCombatCharacter:

KilledNPC  !FGD

Tells the entity it killed something. Despite the name, this can include a player. This input will be automatically sent by the victim when they die.

physdamagescale <float>

Scales damage energy when this character is hit by a physics object. With a value of 0 the NPC will take no damage from physics.

DamageFilter:

SetDamageFilter <string>

Sets the entity to use as damage filter. Pass in an empty string (no parameter) to clear the damage filter.

Parentname:

SetParent <string>

Move with this entity. See Entity Hierarchy (parenting).

SetParentAttachment <string>

Change this entity to attach to a specific attachment point on its parent. The entity will teleport so that the position of its root bone matches that of the attachment. Entities must be parented before being sent this input.

SetParentAttachmentMaintainOffset <string>

As above, but without teleporting. The entity retains its position relative to the attachment at the time of the input being received.

ClearParent

Removes this entity from the the movement hierarchy, leaving it free to move independently.

Outputs

BaseNPC Outputs Expand

OnDamaged Fired when this NPC takes damage (!activator is the damage inflictor). OnDamagedByPlayer Fired when this NPC is hurt by a player (!activator is the attacker or vehicle driver [if friendly fire]). OnDamagedByPlayerSquad Fired when this NPC is hurt by a player OR by one of the player's squadmates (!activator is the attacker or vehicle driver [if friendly fire]). OnDeath Fired when this NPC is killed (!activator is the killer). OnDenyCommanderUse Fired when this NPC has refused to join the player's squad. OnForcedInteractionAborted Fired when the NPC aborts a forced interaction for some reason (target NPC died, couldn't be pathed to, etc.). OnForcedInteractionStarted Fired when the NPC starts a forced interaction. OnForcedInteractionFinished "NPCs in actbusies can no longer perform dynamic interactions." Todo: What does this mean? OnHalfHealth Fired when this NPC reaches half of its maximum health. OnHearCombat Fired when this NPC hears combat sounds. OnHearPlayer Fired when this NPC hears the player. OnHearWorld Fired when this NPC hears a sound (other than combat or the player). OnFoundEnemy <targetname> Fired when this NPC establishes line of sight to its enemy. OnLostEnemy Fired when this NPC loses its enemy. Usually due to the enemy being killed/removed, or because this NPC has selected a newer, more dangerous enemy. OnLostEnemyLOS Fired when this NPC loses line of sight to its enemy. OnFoundPlayer <targetname> Fired when this NPC establishes line of sight to its enemy, and that enemy is a player. OnLostPlayer Fired when this NPC loses its enemy, and that enemy was a player. Usually due to the enemy being killed/removed, or because this NPC has selected a newer, more dangerous enemy. OnLostPlayerLOS Fired when this NPC loses line of sight to its enemy, and that enemy is a player. OnSleep Fired when this NPC enters a sleep state. OnWake Fired when this NPC comes out of a sleep state.

See also

• npc_turret_floor
• npc_turret_ceiling