Prop tractor beam

An excursion funnel in Portal 2.

Template:Portal2 point It is an emitter for a tractor beam.

Excursion funnels are a puzzle element of Portal 2 that work like tractor beams. Objects (like turrets and cubes) and players that touch blue funnels slowly drift away from the emitter, unaffected by gravity. Players can remove objects and themselves from the funnel but can not move against the flow.

Some funnels are connected to buttons. When activated, these funnels reverse direction and turn orange, drawing things towards their emitter instead of pushing things away.

Like bridges and lasers, funnels can be extended through portals.

Keyvalues

Linear Force ([todo internal name (i)]) <float>

Linear force to apply to objects in the beam. The color and direction of spin will automatically change when the value becomes negative. Most Valve created Excursion Funnels have a linear force of 250, so likewise the reverse funnel should be -250.

Disable Emitter Particles ([todo internal name (i)]) <boolean>

Disable the whirly particles on the emitter.

Use 128 model ([todo internal name (i)]) <boolean>

Use the tractor beam projector model that fits within a 128 unit square (the default model is 167 units wide)

Name (targetname) <string>[ Edit ]

The name that other entities refer to this entity by, via Inputs/Outputs or other keyvalues (e.g. parentname or target).
Also displayed in Hammer's 2D views and Entity Report.

See also:  Generic Keyvalues, Inputs and Outputs available to all entities

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.

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

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.

BaseProjector:

Start Enabled (StartEnabled) <boolean>

If the projector should start enabled.

Disable Placement Helper (DisableHelper) <boolean>

Disable the automatically-created placement helper to prevent it from fighting with a custom one.

Render in Fast Reflections (drawinfastreflection) <boolean> (in all games since )

If enabled, this entity will render in fast water reflections (i.e. when a water material specifies $reflectonlymarkedentities) and in the world impostor pass.

Inputs

SetLinearForce <floatRedirectInput/float>

Set the linear force applied to objects in the beam.

Parentname:

SetParent <stringRedirectInput/string>

Move with this entity. See Entity Hierarchy (parenting).

SetParentAttachment <stringRedirectInput/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 <stringRedirectInput/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.

BaseProjector:

Enable

Enables projection from this projector.

Disable

Disables projection from this projector.

Reflection:

DisableDrawInFastReflection  (in all games since )

Turns off rendering of this entity in reflections when using $reflectonlymarkedentities in water material.

EnableDrawInFastReflection  (in all games since )

Turn on rendering of this entity in reflections when using $reflectonlymarkedentities in water material.

Creation

Each funnel consists of a prop_tractor_beam and a player clip in front. Funnels often have a light in front of them for a soft blue glow (with an approximate brightness of 50 120 250 50). This is sometimes left out when the beam is reversible because it conflicts with the orange colour of the funnel; a simple workaround, however, is to place two lights - one blue, one orange - and have them be enabled/disabled by the same event as that which reverses the funnel.

In order to create a wall that will let the tractor beam to go through it but it will block player's or a prop_weighted_cube from passing through, three separate brushes/entities must be combined.

• func_brush brush entity with a Solidity property set to "Never Solid" (will be the only visible brush to the player)
• player clip brush will block player's movements
• func_clip_vphysics brush entity will block weighted cube movement

External links

• Example map using this tutorial. VMF included.