Phys constraint

From Valve Developer Community

This point-based entity is available in all Source games.

Table of contents

1 Entity Description 2 Keyvalues 3 Flags 4 Inputs 5 Outputs

Entity Description

A constraint that keeps the relative position and orientation of two objects fixed. Can be used for 'gluing' several physics props together.

• See also phys_lengthconstraint to keep the distance fixed but not the orientation.

Keyvalues

• targetname <target_source>

Defines the name that other entities refer to this entity by.

• hammerid [Episode Two Update]

<integer readonly> This id is used for debugging purposes in Hammer.

• attach1 <target_destination>

One of the entities to constrain

• attach2 <target_destination>

The other entity to constrain

• constraintsystem <target_destination>

The name of a phys_constraintsystem that this constraint should be a part of. All constraints on a set of entities should be placed in the same system, or they will fight each other during simulation.

• forcelimit <float>

The amount of force an impact must apply to the constraint to break it. Measured in pounds. A way of calculating this is to set it to the mass of an object that would break this constraint if it were resting on the constrainted objects.

• torquelimit <float>

The amount of torque required to break the constraint. Measured in pounds*distance (pounds*inches). 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.

• breaksound <sound>

A sound played when the constraint is broken.

Flags

• 1: No Collision until break
• 2: not used
• 4: Start inactive
• 8: Change mass to keep stable attachment to world

Inputs

• Kill

Removes this entity from the world.

• KillHierarchy

Removes this entity and all its children from the world.

• 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 == infinite)>

• FireUser1-4

Causes this entity's OnUser1-4 outputs to be fired. See User Inputs and Outputs.

• Break

Force the constraint to break.

• TurnOn

Enable the constraint. Do this when the objects don't exist when the constraint spawns, or when you have deactivated the constraint. Broken constraints can not be turned on. They have been deleted.

• TurnOff

Disable this constraint.

Outputs

• OnUser1-4

Fired in response to FireUser1-4 inputs. See User Inputs and Outputs.

!activator = activator

• OnBreak

Fired when the constraint breaks.