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Hydros

Hydros are beams whose length can be varied on demand.

They’re used for many things, including steering racks, hydraulic cylinders, and actuators for doors.

Their length is defined using electrics .

With a factor of 1, sending a command of 1 to a beam will cause it to double in length, while a command of -0.5 will cause the beam to half in length. Smaller factors will result in a smaller length variation.

 Required arguments

id1:
name
string
type
Name of the first node
id2:
name
string
type
Name of the second node

 Optional arguments

Some optional arguments are supposed to be used together, and overwrite other arguments. Others are free to be used with any other arguments. It depends how the hydro is controlled by the input.

 Common optional arguments

These can be used with any other arguments.

inputSource
name
number
type
steering
default
Defines the electrics that will be used to actuate this hydro
inputCenter
name
number
type
0
default
Offset the hydro’s center.
Changes the electric value that will arrive at the hydro’s center. Used to offset the hydro’s center value. Has no effect on the hydro’s limits.
inputInLimit
name
number
type
-1
default
The electric value at which the hydro will be fully in.
All values of the electric below this will result in the hydro staying at full lock.
inputOutLimit
name
number
type
1
default
The electric value at which the hydro will be fully out.
All values of the electric above this will result in the hydro staying at full lock.
inRate
name
number
type
2
default
How fast the hydro contracts
outRate
name
number
type
inRate
default
How fast the hydro expands
autoCenterRate
name
number
type
inRate
default
How fast the hydro contracts towards the center
steeringWheelLock
name
number
type
Defines how much steering wheel angle this hydro will match to

This is center to lock angle. Standard steering will be around 450~500, with older cars and trucks having slightly more angle, and racing cars having less angle.

This drives the “steering” electric used for steering wheel props.

 Proportional asymmetrical control

Use these together when you want to change the minimum and maximum length of the hydro proportionally to the spawn length, but with different proportion for extension and retraction. These get overwritten by “inExtent”, “outExtent”, “factor” and “extentFactor” from the next groups.

inLimit
name
number
type
0
default
Defines the shortest the hydro can become.
Defined as a portion of the initial length, with 0.5 meaning the hydro can become half its initial length, and 1.0 meaning it cannot become shorter than its initial length.
outLimit
name
number
type
2
default
Defines the longest the hydro can become.
Defined as a portion of the initial length, with 2.0 meaning the hydro can become twice its initial length, and 1.0 meaning it cannot become longer than its initial length.
inputFactor
name
number
type
1
default
Multiplier of the input value.

A value of 0.5 will result in the hydro extending by half the outLimit value proportional to its length when the input is 1, and compressing by half the inLimit value proportional to its length when the input is -1.

Negative values will cause the hydro to contract instead of expanding with positive input values and vice versa.

 Absolute asymmetrical control

Use these together when you want to change the minimum and maximum length of the hydro by direct values in meters, but with different values for extension and retraction. These get overwritten by “factor” and “extentFactor” from the next groups.

outLimit
name
number
type
Defines how much longer the hydro can become in meters.
Defined as absolute length, with 1.0 meaning the hydro can become 1m longer than its initial length, and 0.0 meaning it cannot become longer than its initial length.
inLimit
name
number
type
Defines how much shorter the hydro can become in meters.
Defined as absolute length, with 1.0 meaning the hydro can become 1m shorter than its initial length, and 0.0 meaning it cannot become shorter than its initial length.
inputFactor
name
number
type
1
default
Multiplier of the input value.

A value of 0.5 will result in the hydro extending by half the outLimit value when the input is 1, and compressing by half the inLimit value when the input is -1.

Negative values will cause the hydro to contract instead of expanding with positive input values and vice versa.

 Proportional symmetrical control

Use this when you want to change the minimum and maximum length of the hydro proportionally to the spawn length, with the sane proportion for extension and retraction. Gets overwritten by “extentFactor” from the next group.

factor
name
number
type
Extension/compression limit as a proportion of the hydro’s length.

A value of 0.5 will result in the hydro halving in length at when the input is -1, and an extension to 1.5 times the hydro’s initial length when the input is 1.

Negative values will cause the hydro to contract instead of expanding with positive input values and vice versa.

 Absolute symmetrical control

Use this when you want to change the minimum and maximum length of the hydro by direct values in meters, with the same values for extension and retraction.

extentFactor
name
number
type
Extension/compression limit in meters.

A value of 0.5 will result in the hydro reducing its length by 0.5m at when the input is -1, and increasing it by 0.5m when the input is 1.

Negative values will cause the hydro to contract instead of expanding with positive input values and vice versa.

 Other arguments

As they are for the most part a special type of beam , hydros can use a most of the arguments related to standard beams like beamSpring, beamDamp, beamPrecompression, etc.

 Examples 

    "hydros": [
        ["id1:","id2:"],
        {"beamPrecompression":1.0, "beamType":"|NORMAL", "beamLongBound":1, "beamShortBound":1},
        {"beamSpring":8001000,"beamDamp":50,"beamDeform":"FLT_MAX","beamStrength":125000},
        ["fh6r","fx5l", {"factor": 0.14,"steeringWheelLock":510,"inRate":1.25,"outRate":1.25}],
        ["fh6l","fx5r", {"factor":-0.14,"steeringWheelLock":510,"inRate":1.25,"outRate":1.25}],
        {"beamPrecompression":1.0, "beamType":"|NORMAL", "beamLongBound":1, "beamShortBound":1},
    ],

    "hydros": [
        ["id1:","id2:"],
        {"beamDeform":175000,"beamStrength":"FLT_MAX"},
        {"beamSpring":20001000,"beamDamp":5000},
        {"beamPrecompression":1.0},
        {"breakGroupType":1},
        {"breakGroup":"dump_hydros"},
        ["tfr2r","tfr1r", {"inputSource":"tilt","inLimit":0,"outLimit":1.9,"inRate":0.2,"outRate":0.2,"inputFactor":1.0}],
        ["tfr2l","tfr1l", {"inputSource":"tilt","inLimit":0,"outLimit":1.9,"inRate":0.2,"outRate":0.2,"inputFactor":1.0}],
        {"beamPrecompression":1.0},
        {"breakGroupType":0},
        {"breakGroup":""},
    ],
Last modified: October 19, 2026

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