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Revision as of 14:55, 30 April 2016 by Henke37 (talk | contribs) (missing inputs)
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func_smokevolume is a brush entity available in all Source games.

Entity description

A brush entity that spawns smoke particles within its volume, commonly used for large, localised areas of fog. Use the trigger texture or the fog texture.

Warning.png Warning: Smoke volumes should be used sparingly as they can decrease performance in heavily detailed scenes, or scenes with high amounts of action. Particle systems may be cheaper to use, depending on CPU usage restraints.
Warning.png Warning: Smoke volumes shouldn't be placed in the same volume as func_precipitation is. Otherwise engine may freeze at the end of loading the level. It is probably caused by some particle coding that do not accept this two types of sprites to render at once (in the same volume).
Note.png Note: The default material is particle/smoke_grenade1, which does not exist. However, particle/particle_smokegrenade does.


Particle Color1 (R G B) <color255>
Particle color 1
Particle Color2 (R G B) <color255>
Particle color 2
Material <material>
The material to use for the particles
Particle Draw Width (units) <float>
The size of the particles, in units/inches. (Typical Values: 128,175,200,500,512)
Particle Spacing Distance (units) <float>
The distance between the particles inside the volume. The lower the number, the denser the particles, and the more overdraw there will be. It is best to keep it as high as you can without it looking bad. (Typical Values: 125,150,200 and sometimes 80 or 480)
Density Ramp Speed (seconds) <float>
Time to go from density 0 to density 1, in seconds.
Rotation Speed (degrees/sec) <float>
The speed that the particles should rotate, in degrees per second. (Typical Values: 3,10)
Movement Speed (units/sec) <float>
The speed that the particles should move around, in units/inches per second.
Density [0..1] <float>
Particle density, from 0 to 1. (Typical Values: .1-.5)


Name (targetname) <string>
The targetname that other entities refer to this entity by.
Entity Scripts (vscripts) <scriptlist> (in all games since Left 4 Dead 2)
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 Left 4 Dead 2)
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.
Note.png Note: Try to avoid expensive operations in this function, as it may cause performance problems.


  • 1 : Emissive
Changes how the smoke particles are drawn. Emissive is 4 times more expensive to render.


Bug.png Bug: All inputs are missing in Team Fortress 2
SetRotationSpeed <float>
Set the particle rotation speed (in degrees per second).
SetMovementSpeed <float>
Set the particle movement speed (in inches per second).
SetDensity <float>
Set the particle density. It should be a range from 0 to 1.


Removes this entity from the world.
Removes this entity and its children from the world.
Note.png Note: Entities already remove orphaned children upon being removed, but this input removes all children on the same frame, being marginally faster than Kill.
AddOutput <string>
Adds a keyvalue/output to this entity. It can be potentially very dangerous, use with care.
KV Format: <key> <value>
I/O Format: <output name> <targetname>:<inputname>:<parameter>:<delay>:<max times to fire, -1 means infinite>
FireUser1 to FireUser4
Fire the OnUser outputs; see User Inputs and Outputs.
Use  !FGD
Same as a player invoking +use; may not do anything depending on the entity. Can also be invoked by firing an output that does not specify an input.
RunScriptFile <script> (in all games since Left 4 Dead 2)
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 Left 4 Dead 2)
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.png Bug: In Left 4 Dead 2, the code is executed in the script scope of the entity that fires the output, not the one receiving the input.
Warning.png Warning: Never try to pass string parameters to a script function with this input. It will corrupt the VMF structure because of the nested quotation marks, which then must be removed manually with a text editor.
CallScriptFunction <string> (in all games since Left 4 Dead 2) !FGD
Execute a VScript function in the scope of the receiving entity.
SetLocalOrigin <coordinates> (in all games since Alien Swarm) !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 Alien Swarm) !FGD
Set this entity's angles.



Fired when an entity stops touching this trigger. Only entities that passed this trigger's filters will cause this output to fire. (activator is the exiting entity)
Warning.png Warning: This includes entities which are deleted while inside the trigger. In this case activator will be invalid.
Fires when the last entity in the entity's area exits this trigger or when this entity is disabled. Only entities that passed this trigger's filters are considered. (activator is the last exiting entity)
OnTouching  (in all games since Half-Life 2: Episode TwoHalf-Life 2: Episode Two)
OnNotTouching  (in all games since Half-Life 2: Episode TwoHalf-Life 2: Episode Two)
Fired when the TouchTest input is called.


Fired when an entity starts touching this trigger. The touching entity must pass this trigger's filters to cause this output to fire. (activator is the toucher)
Fired repeatedly with a delay when an entity is in this trigger's volume. Delay is defined by Delay Before Reset key.


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 Left 4 Dead Left 4 Dead 2)
This output fires when the entity is killed and removed from the game.