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<Half-Life><Half-Life 2> func_train is a point entity available in the Half-Life series. It is a used leftover from Quake that ping-pongs between the start and end of its path. In GoldSrc, it is primarily used for looping auto-scrolling backgrounds. In Source, it has been superseded in usability with the introduction of parenting, rendering it obsolete but still functional.

Entity Description

FGD Code

@SolidClass base(Targetname, Origin, RenderFields) = func_train
	spawnflags(flags) =
		8 : "Non-solid" : 0
	texframeindex(integer) : "Initial Brush Frame Index" : : "Use this to set the initial frame of materials with multiple frames in the brush"
	target(target_destination) : "First path_corner"
	noise1(sound) : "Movement Sound" : : "The sound to play when the train moves."
	noise2(sound) : "Stop Sound" : : "The sound to play when the train stops moving."
	speed(float) : "Speed" : "50.000000" : "Speed at which the brush moves."
	volume(float) : "Sound volume [0.0, 10.0]" : "0.000000"
	dmg(float) : "Crush Damage" : "0.000000"
	input Toggle(void) : "Toggle movement"
	input Start(void) : "Start movement"
	input Stop(void) : "Stop movement"
	input Use(void) : "Toggle movement - has a different functionality than Toggle"


  • Targetname:

Name (targetname) <string>
The targetname that other entities refer to this entity by.
Entity Scripts (vscripts) <scriptlist> (New with 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> (New with 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:Try to avoid expensive operations in this function, as it may cause performance problems.
  • Origin:

Origin (X Y Z) (origin) <origin>
The position of this entity's center in the world. Rotating entities typically rotate around their origin.
  • RenderFields:
Render Mode (rendermode) <choices>
Set a non-standard rendering mode on this entity.
Render FX / Transparency (0 - 255) (renderamt) <integer>
Transparency amount, requires a Render Mode other than Normal. 0 is invisible, 255 is fully visible.
Render Color (R G B) (rendercolor) <color255>
Color tint.
Disable Receiving Shadows (disablereceiveshadows) <boolean>
Prevent the entity from receiving shadows on itself.


Render FX (renderfx) <choices>
Preset pattern of appearance effects.
To do: 18-21, 25
  • texframeindex
<integer> Use this to set the initial frame of materials with multiple frames in the brush
  • target
<target_destination> First path_corner
  • noise1
<sound> The sound to play when the train moves.
  • noise2
<sound> The sound to play when the train stops moving.
  • speed
<float> Speed at which the brush moves.
  • volume
<float> Sound volume 0.0 to 10.0
  • dmg
<float> Crush Damage


  • 8 : Non-solid


  • Targetname:

Removes this entity and any entities parented to it from the world.
Functions the same as Kill, although this entity and any entities parented to it are killed on the same frame, being marginally faster than Kill.
AddOutput <string>
Evaluates a keyvalue/output on this entity. It can be potentially very dangerous, use with care.
Format: <key> <value>
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. Can also be invoked by creating an output that does not specify an input.
This input is not included in Valve's FGDs.
RunScriptFile <script> (New with 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> (New with 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: 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: 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> (New with Left 4 Dead 2) !FGD
Execute a VScript function in the scope of the receiving entity.
SetLocalOrigin <coordinates> (New with 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> (New with Alien Swarm) !FGD
Set this entity's angles.


Alpha <integer>
Sets the entity's transparency to a number from 0 (invisible) to 255 (fully visible). Requires the entity to have its Render Mode (rendermode) set to a number other than 0.
Color <color255>
Sets an RGB color for the entity.
  • Toggle
Toggle movement between start and stop
  • Start
Start movement
  • Stop
Stop movement
  • Use
Toggle movement - the train will move only when the input is triggered.


  • Targetname:

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