npc_strider

npc_strider is a point entity available in Half-Life 2.

Striders are the largest known creatures in the Combine arsenal. Simply parading a Strider down a street can be enough to give players a sense of unease, but they are unwieldy and should be used only after great care and consideration. A Strider on every street corner is a great way to destroy their effect!

A Strider has three forms of attack: its Pulse turret, which will slowly strafe across targets, its Warpspace cannon that will evaporate all dynamic entities it touches (but needs to be triggered by the mapper), and its legs, which in the right circumstances can stomp down on NPCs and 'impale' or skewer them.

Tip:Striders will only attack NPCs; to make them attack parts of their environment/other non-NPCs, use npc_bullseyes.

A Strider is a Flying NPC that uses info_node_air_hint of type "Strider Node" for navigation. It can only move in straight lines between these entities (though it can turn freely).

It is also very large, and requires plenty of space in order to move around. They need at least 300 units to fit on the ground and around 540 to stand upright. Striders do not require open terrain however: their long legs allow them to cross over nearly anything up to a certain height.

• Scanners can be used to extend a Strider's line of sight when properly flagged. Every time they take a photo, the location of the target NPC/player is transmitted to nearby Striders through an entity called bullseye_strider_focus, which they will then hate.
• In Episode One, Striders have a new attack. They're capable of firing much faster and accurately than they could in Half-Life 2. They are better at tracking the players movements as well.

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

Dedicated Console Variables

Dedicated Console Variables:

npc_strider_height_adj <int>

Adjust strider's z axis of its origin (Default: 0).

npc_strider_shake_ropes_magnitude <float>

Magnitude at which the strider's footsteps will shake ropes (Default: 150).

npc_strider_shake_ropes_radius <float>

Radius in which ropes will shake by the footsteps (Default: 1200).

sk_strider_health <int>

Strider spawn health (Default: 350).

sk_strider_num_missiles1 <float>

Rockets required to take down an easy strider (Default: 5).

sk_strider_num_missiles2 <float>

Rockets required to take down a medium strider (Default: 7).

sk_strider_num_missiles3 <float>

Rockets required to take down a hard strider (Default: 7).

strider_always_use_procedural_height <bool>

Uses calculated height if not set (Default: 0).

strider_ar2_altfire_dmg <float>

The amount of damage an AR2 grenade (combine ball) does to a strider. (Default: 25)

strider_distributed_fire <bool>

Switch targets once in a while. (Default: 1)

strider_eyepositions <bool>

Draw a 3D cross at the standing and crouched eye positions (Default: 0).

'strider_free_knowledge <float>

Todo: Add a description for this variable.

(Default: 0)

strider_free_pass_cover_dist <float>

Todo: Add a description for this variable.

(Default: 120)

strider_free_pass_duration <float>

Todo: Add a description for this variable.

(Default: 2)

strider_free_pass_move_tolerance <float>

Todo: Add a description for this variable.

(Default: 320)

strider_free_pass_refill_rate<float>

Todo: Add a description for this variable.

(Default: 0)

strider_free_pass_start_time<float>

Todo: Add a description for this variable.

(Default: 3)

strider_idle_test <bool>

Disables minigun and sets the schedule to standing idle (Default: 0).

strider_immolate <bool>

Unused: Strider immolation toggle(Default: 0).

strider_pct_height_no_crouch_move <float>

A percentage used while calculating ideal crouch height (Default: 90).

strider_peek_eye_dist<float>

Eye distance (Default: 1).

strider_peek_eye_dist_z<float>

Eye distance z (Default: 4).

strider_peek_time <float>

Gives players this much time before shooting at them (player in slot 1 only)(Default: 0).

strider_peek_time_after_damage <float>

Gives players this much time before shooting at them after being attacked (player in slot 1 only)(Default: 4).

strider_show_cannonlos <bool>

Draw cannon's line of sight (Default: 0).

strider_show_focus <bool>

Draw a 3d cross at the origin of the strider's target (Default: 0).

strider_show_weapon_los_condition <bool>

Draw weapon's line of sight (condition)(Default: 0).

strider_show_weapon_los_z <bool>

Draw weapon's line of sight (z)(Default: 0).

strider_test_height <float>

Sets the strider's ideal height to this if it's greater than .1 (Default: 0).

Only works with strider_always_use_procedural_height on.

Keyvalues

Disable physics (reduce CPU) (disablephysics) <boolean>

Model (model) <choices>

• Standard Strider: models/combine_strider.mdl
• The Strider that fights Dog: models/combine_strider_vsdog.mdl

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.

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.

• 65536 : Can Stomp Player
  Note:This doesn't mean the strider won't step on the player, it just means the strider will not try to stab the player.

Inputs

SetMinigunTime <float>

Time to shoot at any set minigun target.

SetMinigunTarget <targetname>

Strider will shoot minigun at this target.

SetCannonTarget <targetname>

Strider will shoot cannon at this target.

FlickRagdoll

Strider will flick anyone it's skewered.

StartPatrol

Start patrolling back and forth along the current track.

Bug: non-functional, FGD error  [todo tested in ?]

StopPatrol

Stop patrolling back and forth along the track. This will cause the helicopter to come to rest at the track which he's currently flying toward.

Bug: non-functional, FGD error  [todo tested in ?]

ChooseFarthestPathPoint

When tracking an enemy, choose the point on the path furthest from the enemy, but still in firing range.

Bug: non-functional, FGD error  [todo tested in ?]

ChooseNearestPathPoint

When tracking an enemy, choose the point on the path nearest from the enemy.

Bug: non-functional, FGD error  [todo tested in ?]

Crouch

Crouch down.

Stand

Stand up from crouch.

DisableCrouchWalk

Disables the ability of the Strider to Crouchwalk.

EnableCrouchWalk

Enables the ability of the Strider to Crouchwalk.

SetTargetPath <targetname>

Set a path for the Strider to move along. The Strider will first move to the closest point on the path.

Tip:Striders will not deviate from this path by default (even in combat). The only way to make them deviate is through scout scanners or inputs.

ClearTargetPath

Clear the Strider patrol path.

CrouchInstantly

Crouch instantly. This makes the Strider pop to a crouch. Do not do this where players can observe.

EnableAggressiveBehavior

Enables Striders' new minigun attack (New with HL2 Episode One!). The Strider will fire more rapidly and with greater precision.

DisableAggressiveBehavior

Stop using aggressive behavior. (Revert to normal)

StopShootingMinigunForSeconds <float>

Stop shooting the minigun for a period of time (specify seconds as parameter).

DisableCrouch

Prevents the Strider from crouching.

DisableMoveToLOS

Prevents the Strider from seeking Line of Sight to target. Essentially, this prevents the Strider from switching between standing and crouching on its own. Use Crouch/CrouchInstantly or Stand to manually change its state.

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.

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.

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