phys_pulleyconstraint

phys_pulleyconstraint is a point entity available in all Source games. It is a constraint that is essentially two length constraints and two points. Imagine it as a virtual rope connected to two pulleyed objects, specified in the Entity 1 (attach1) and Entity 2 (attach2) keyvalues, each suspended from a pulley above them.

Pulley point 1 - the pulley from which Entity 1 is always suspended from - is the origin of this constraint entity.

Pulley point 2 - the pulley from which Entity 2 is always suspended from - is the position of the "blue ball", set by altering the Pulley Position 2 (position2) keyvalue directly, or by using the Helper Tool.

The constraint keeps the sum of the distances between the pulley points and their suspended objects constant.

Keyvalues

Additional Length (addlength) <float>

Add (or subtract) this amount to the rest length of the pulley rope.

Pulley Gear Ratio (gearratio) <float>

Add (or subtract) this amount to the rest length of the pulley rope.

Pulley Position 2 (position2) <vector>

The position of the pulley for Entity 2. The pulley for Entity 1 is the origin of this constraint entity. Entity 1 is always suspended from pulley point 1, and Entity 2 is always suspended from pulley point 2.

TwoObjectPhysics:

Entity 1 (attach1) <targetname>

Entity 2 (attach2) <targetname>

The entities to constrain. Leave one or the other field blank to constrain to the world.

Note:Only one entity will be constrained, even if several share the given targetname.

Constraint System Manager (constraintsystem) <targetname>

A phys_constraintsystem that this constraint should be a part of. This avoids the "jiggling" caused by constraints applied to the same set of entities fighting with each other.

Force Limit to Break (forcelimit) <float>

Impact force required to break the constraint, in pounds. 0 means infinite. A way of calculating this is to set it to the weight of an object that would break the constraint if it were resting on its objects.

Torque Limit to Break (torquelimit) <float>

Torque required to break the constraint, in pounds*inches. 0 means infinite. A way of calculating this is to multiply any reference mass by the resting distance (from the center of mass of the object) needed to break the constraint.

Play Sound on Break (breaksound) <string>

A sound played when the constraint is broken.

Follow teleport distance (teleportfollowdistance) <float>

If one constrained object teleports more than this many units away, the other will teleport with it.

Name (targetname) <string>

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

Flags

• 1 : No Collision until break
• 2 : Keep Rigid

No Collision until break : [1]
Start inactive : [4]
Change mass to keep stable attachment to world : [8]
Do not connect entities until turned on : [16]

Inputs

TwoObjectPhysics:

Break

Force the constraint to break.

TurnOn

Enable the constraint; do this if the constrained objects don't exist when it spawns. Note that broken constraints cannot be turned back on as they have been deleted.

TurnOff

Disable the constraint.

Outputs

TwoObjectPhysics:

OnBreak

Fired when the constraint breaks.

See also

• A Counter-weighted Door.