path_track
... 
| path_track | |
|---|---|
 | |
| Type | Point entity |
| Engine |  Source |
| Availability | In all games |
path_track is a point entity available in all Source games. It is used to build paths for other entities to follow. Each path_track is a node in the path, each holding the name of the next path_track in the path.
Contents
Automated track creation
Cloning (Shift-drag) this entity will activate a feature used to automatically and quickly create a track. This feature will alter both the Name keyvalue, and the Next Stop Target keyvalue, so that a track is created between the source and the clone. More specifically, Hammer will add a counter after the Name keyvalue of the clone, or increment this counter if it already exists, creating a unique name in a series. If a name is completely omitted, it will simply name the clone "path".
If a Next Stop Target keyvalue has been specified, it will also alter this keyvalue of the source, to the name of the clone, resulting in a track being drawn between them.
Reversing over a path_track
Bug: Normally, when given a StartBackward or Reverse input, a func_tracktrain will begin moving in reverse direction at its normal speed. However, due to coding glitches, if some of the path_tracks involved in the course have their "New Train Speed" property value set to 0, the train may stop moving, or may move in the wrong direction. This issue can be solved by setting the "New Train Speed" property in the involved tracktrains to a number other than zero.Parenting
A set of tracks can be parented. However, all tracks and the train running on them must be parented to the same object for movement to behave correctly. Failure to do so will lead to an intentional crash.
Keyvalues
- Next Stop Target (target) <targetname>
- The next path_track in the path. Bug: If this is not set and a func_tanktrain starts here, using the StartForward output on the func_tanktrain will cause the map to not load.
- Branch Path (altpath) <targetname>
- An alternative path_track to be the next node in the path. Useful for making branching paths. Use the
ToggleAlternatePath/EnableAlternatePathinputs to make the alternative path active. Bug: If this value is set to anything that isn't a path_track, the game will crash without notice upon loading the level.
- New Train Speed (speed) <float>
- When the train reaches this path_track, it will set its speed to this speed. Speeds higher than the max speed of the train are clamped.
- Path radius (radius) <float>
- Used by NPCs who follow track paths (attack chopper/gunship). This tells them the maximum distance they're allowed to be from the path at this node.
- Orientation Type (orientationtype) <choices>
- The way that the path follower faces as it moves through this path track.
- 0 : No change
- 1 : Face direction of motion
- 2 : Face this path_track's angles
Bug: "Face this path_track's angles" doesn't work unless the train has "change angles" set to linear blend or ease in/out.Targetname:
- Name
(targetname)<string> - The targetname that other entities refer to this entity by.
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.
Angles:
- Pitch Yaw Roll (Y Z X)
(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.
Flags
- [
1] : Disabled
- [
2] : Fire once
- [
4] : Branch Reverse (Alternative path is for going backwards, not forwards)
- [
8] : Disable train
- [
16] : Teleport to THIS path track
- [
32] : TF2 payload uphill zone
- [
64] : TF2 payload downhill zone
Inputs
ToggleAlternatePath- Cause the track to toggle to/from its alternate path.
EnableAlternatePath- Enable the alternate path of the track.
DisableAlternatePath- Disable the alternate path of the track.
TogglePath- Cause the track to toggle on/off
EnablePath- Enable the track.
DisablePath- Disable the track.
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,AddOutput,OnUser1:SetParent:!activator:0.0:-1"
// Arguments can be left blank, but the empty blank should still be contained.
//// Raw text:
"OnUser1" "!self,AddOutput,OnUser1: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.
FireUser1toFireUser4- Fires the respective
OnUseroutputs; 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.
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
) (also in 
)- 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) (also in )- 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.Note: Backtick characters ` are replaced with quotation marks at runtime, allowing quotation marks to be used when normally not possible.
CallScriptFunction<string> (in all games since) (also in ) !FGD- Calls a VScript function defined in the scope of the receiving entity.
TerminateScriptScope(only in) !FGD- Destroys the script scope of the receving 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.
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
OnPass- Fired when any entity following this path passes this path_track node.
OnTeleport- Fired when any entity following this path teleports directly to this path_track node.
Targetname:
OnUser1toOnUser4- These outputs each fire in response to the firing of the like-numbered
FireUser1toFireUser4Input; see User Inputs and Outputs.
OnKilled(only in)- This output fires when the entity is killed and removed from the game.
See also
- func_tracktrain - The entity that moves between these paths, and Trains.
