func_nav_blocker

func_nav_blocker is a brush entity available in all Source games since Left 4 Dead . and also in . It blocks nav areas touching its AABB to restrict NPCs / Bots from crossing over it.

 Bug: In , Ifprop_door_rotatingorfunc_physboxresides on the same areas, send anUnblockNavinput along aBlockNavinput. Else the console reports "Area navsquare#[ID] already blocked by a different team ID.^[confirm]

 Note: The entity won't block nav areas automatically on spawn (except in ). It is best practice to have eitherBlockNavorUnblockNavinputs sent withOnMultiNewRound.

 Note: This entity blocks navigation areas using its bounding box! Complex brush models will not work.

Keyvalues

NavBlocker:

Team(s) to block (teamToBlock) <choices>

Team this entity should block.

• -1 : Everyone
• 2 : Red , Survivors , Terrorists
• 3 : Blue , Infected , Counter-Terrorists

 Warning:  teamToBlock non-functional, always blocks either for both teams or for no team.

Affects Flow? (affectsFlow) <boolean> (only in )

Does this Nav Blocker block flow in the level? Only Nav Blocker with this enabled will cause flow recomputation on blocking/unblocking.

 Warning:  This can cause a flow error if it blocks the only path to the level's goal.

Recheck Breakables <boolean> (only in ) 

Deprecated. Appears to respond to any changes to breakables, even though aBlockNav/UnblockNavinput is fired anyways from the breakable prop anyway.

Brush:

Minimum Bounding Box Size (mins) <vector> !FGD

Maximum Bounding Box Size (maxs) <vector> !FGD

Starting at the brush's origin, mark a bounding box's corner as this far away. Both are required at the same time so one side of the bounding box isn't empty.

 Note: To translate a brush's size in Hammer to these keys, first divide the size value shown in Hammer by 2. Apply the result to themaxskey, then apply the inverted variant (multiply / divide by -1) for theminskey.

 Note: If collisions is already set, it must be set back to Bounding Box (solid 2).

Collisions (solid) <choices>

Method of collision for this entity.

• 0: None
• 1: BSP (QPhysics) !FGD
   Bug: In , if an entity using QPhysics collisions is hit by Gel, the game will crash!
• 2: Bounding Box
• 3: Oriented Bounding Box (Use for runtime spawned brush entities meant to be rotated) !FGD
• 4: Oriented Bounding Box, constrained to Yaw only !FGD
• 5: Custom/Test (Usually no collision with anything) !FGD
• 6: VPhysics

Model Index (modelindex) <short> !FGD

Given the number index from dumping thecl_precacheinfo modelprecachetable, sets entity model to of the index.

 Warning: If an entity has animations that will be played, then the set model also must have its own sequences, else the game crashes.

Base:

Name (targetname) <string>

The name that other entities use to refer to this entity.

Parent (parentname) <targetname>

Maintain the same initial offset to this entity. An attachment point can also be used if separated by a comma at the end. (parentname [targetname],[attachment])

 Tip: Entities transition to the next map with their parents

 Tip: phys_constraintcan be used as a workaround if parenting fails.

Global Entity Name (globalname) <string>

When the player transitions to a new map, entities in the new map with matching globalnames will have their previous map's states copied over to it.

Origin (X Y Z) (origin) <coordinates>

The position of this entity's center in the world. Rotating entities typically rotate around their origin.

 Note: Hammer does not move the entities accordingly only in the editor.

Pitch Yaw Roll (X Y Z) (angles) <angle>

This entity's orientation in the world. Pitch is rotation around the Y axis, yaw is the rotation around the Z axis, roll is the rotation around the X axis.

 Note: This works on brush entities, although Hammer doesn't show the new angles.

Response Contexts (ResponseContext) <string>

Pre-defined response system contexts; Format is [key]:[value],[key]:[value],...and so on.

 Tip: Can also be filtered for or against!

Classname (classname) <string> !FGD

Determines the characteristics of the entity before it spawns.

 Tip: Changing classnames using theAddOutputinput can still influence the game's code, like making the classname match one element in the S_PreserveEnts list will make the entity persists on new rounds!

Flags (spawnflags) <integer> !FGD

Toggles exclusive features of an entity, its specific number is determined by the combination of flags added.

Effects (effects) <integer> !FGD

Combination of effect flags to use.

Hammer ID (hammerid) <integer> !FGD

The entity's unique Hammer ID that's auto-generated on map compiles. Mainly used by plugins or debugging commands (like theent_keyvaluecommand). Run-time spawned entities don't have a Hammer ID.

Entity Scripts (vscripts) <scriptlist> (in all games since )

Space delimited list of VScript files (without file extension) that are executed after all entities have spawned. The scripts are all executed in the same script scope, later ones overwriting any identical variables and functions.

Script think function (thinkfunction) <string> (in all games since )

Name of a function in this entity's script which will be called automatically every 100 milliseconds (ten times a second) for the duration of the script. It can be used to create timers or to simulate autonomous behavior. The return value (if present) will set the time until the next call. Try to avoid expensive operations in this function, as it may cause performance problems.

Lag Compensation (LagCompensate) <boolean> (in all games since ) !FGD

Set to Yes to lag compensate this entity. Should be used very sparingly!

Disable for Xbox 360 (disableX360) <boolean> (in all games since ) !FGD

If this entity should automatically be given the 'Disable' input on the Xbox 360 version of Source.

Is Automatic-Aim Target (is_autoaim_target) <boolean> (in all games since ) !FGD

If set to 1, this entity will slow down aiming movement for consoles and joystick controllers when the entity is under the crosshairs.

EnableDisable:

Start Disabled (StartDisabled) <boolean>

Stay dormant until activated (with theEnableinput).

 Warning: Enabled/Disabled state does not prevent blocking of nav areas.

Inputs

NavBlocker:

BlockNav

Starts blocking nav areas.

UnblockNav

Stops blocking nav areas.

 Warning: Nav areas stay blocked even after this is killed or disabled! UseBlockNav/UnblockNavfirst.

Base:

AddContext <string>

Adds to the entity's list of response contexts. Format is <key>:<value>.

AddOutput <string>

Assigns a new keyvalue/output on this entity. For keyvalues, some rely on extra necessary code to be ran and won't work if its simply just changed through this input. There is a strict format that must be followed:

Syntax: 

// Format of changing KeyValues: "AddOutput [key] [value]"
//// Raw text:
"OnUser1" "!self,AddOutput,targetname new_name"

// Format of adding an Output: "AddOutput {targetname}:{inputname}:{parameter}:{delay}:{max times to fire, -1 means infinite}"
//// Raw text:
"OnUser1" "!self:SetParent:!activator:0.0:-1"
// Arguments can be left blank, but the empty blank should still be contained.
//// Raw text:
"OnUser1" "!self:ClearParent::0.0:-1"

ClearContext

Removes all contexts from this entity's list.

ClearParent

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

FireUser1 to FireUser4

Fires the respectiveOnUseroutputs; see User Inputs and Outputs.

Kill

Removes this entity and any entities parented to it from the world.

KillHierarchy

Functions the same as Kill, although this entity and any entities parented to it are killed on the same frame, being marginally faster thanKillinput.

RemoveContext <string>

Remove a context from this entity's list. The name should match the key of an existing context.

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.

Use  !FGD

Same as a player invoking +use; no effect in most cases.

DispatchResponse <string> !FGD

Dispatches a response to the entity. See Response and Concept.

DispatchEffect <string> (removed since ) !FGD

Dispatches a special effect from the entity's origin; see also List of Client Effects. Replaced by the particle system since .

RunScriptFile <script> (in all games since )

Execute a VScript file from disk, without file extension. The script contents are merged with the script scope of the receiving entity.

RunScriptCode <string> (in all games since )

Execute a string of VScript source code in the scope of the entity receiving the input. String quotation may be needed when fired via console.

 Bug: In Hammer, using string arguments will corrupt the VMF file's structure, making the file unviewable for the next Hammer session.

Fix: Remove the string argument manually with a text editor.

CallScriptFunction <string> (in all games since ) !FGD

Execute a VScript function in the scope of the receiving entity.

SetLocalOrigin <coordinates> (in all games since ) !FGD

Send this entity to a spot in the map. If the entity is parented to something, it will be offset from the parent by this amount.

SetLocalAngles <angles> (in all games since ) !FGD

Set this entity's angles.

EnableDisable:

Enable

Disable

Enable/disable this entity from performing its task. It might also disappear from view.

Outputs

Base:

OnUser1 to OnUser4

These outputs each fire in response to the firing of the like-numbered FireUser1 to FireUser4 Input; see User Inputs and Outputs.

OnKilled  (only in )

This output fires when the entity is killed and removed from the game.

See Also

• script_nav_blocker - VScript catered version of func_nav_blocker.