Constraint Property

Summary

The Constraint Property operator modifies the properties of constraints after they are generated. It allows you to adjust stiffness, rest length, damping, and other constraint parameters dynamically. The operator can read values from geometry attributes to modulate these properties, enabling attribute-driven control over constraint behavior.

The Geometry page allows transforming the geometry which affects the constraints by recomputing properties like rest length. This is useful for fine-tuning constraint simulations by editing constraint attributes post-generation. You can selectively modify constraints based on groups, apply scaling factors, or use attribute data to create spatially-varying constraint properties.

Parameters

Page: Geometry

Transform Order Xord – – Sets the overall transform order for the transformations.
Scale Rotate Translate srt
Scale Translate Rotate str
Rotate Scale Translate rst
Rotate Translate Scale rts
Translate Scale Rotate tsr
Translate Rotate Scale trs
Rotate Order Rord – – Sets the order of the rotations within the overall transform order.
Rx Ry Rz xyz
Rx Rz Ry xzy
Ry Rx Rz yxz
Ry Rz Rx yzx
Rz Rx Ry zxy
Rz Ry Rx zyx
Translate T – – Translate the points in the three axes.
Translate Tx
Translate Ty
Translate Tz
Rotate R – – Rotate the points around the corresponding X, Y and Z axes. Angles are given in degrees.
Rotate Rx
Rotate Ry
Rotate Rz
Scale S – – Scale factor for each axis.
Scale Sx
Scale Sy
Scale Sz
Pivot P – – The pivot point for the transform rotates and scales.
Pivot Px
Pivot Py
Pivot Pz
Uniform Scale Scale – Uniform scale multiplier applied to all axes.

Page: Constraints

Constraint Group Constraintgroup – Primitive group containing constraints to modify. Leave empty to modify all constraints.
Enable Enablestiff – Enable modification of stiffness values.
Stiffness Scale Stiffscale – – Scale factor for stiffness (powers of 10). Higher values create more rigid constraints.
1e+10 1e+10
1e+9 1e+9
1e+8 1e+8
1e+7 1e+7
1000000 1000000
100000 100000
10000 10000
1000 1000
100 100
10 10
1 1
0.1 0.1
0.01 0.01
0.001 0.001
0.0001 0.0001
0.00001 0.00001
0.000001 0.000001
1e-7 1e-7
1e-8 1e-8
1e-9 1e-9
1e-10 1e-10
Stiffness Stiffness – Multiplier for stiffness value.
Operation Stiffop – – How to apply the stiffness modification.
Set set
Scale scale
Enable Enabledampratio – Enable modification of damping ratio values.
Damping Ratio Dampingratio – Damping ratio value (0-1). Higher values reduce oscillation.
Operation Dampratioop – – How to apply the damping ratio modification.
Set set
Scale scale
Rest Length Scale Restlengthscale – Modify constraint rest length scale values.
Enable Enablerestscale – Enable modification of rest length scale values.
Rest Length Scale Restscale – Multiplier for rest length. Values above 1.0 create pre-stretched constraints.
Operation Restscaleop – – How to apply the rest length scale modification.
Set set
Scale scale
Enable Enableplasticthreshold – Enable modification of plastic threshold values.
Plastic Threshold Plasticthreshold – Strain threshold before plastic deformation begins.
Operation Plasticthresholdop – – How to apply the plastic threshold modification.
Set set
Scale scale
Enable Enableplasticrate – Enable modification of plastic rate values.
Plastic Rate Plasticrate – Rate of plastic deformation per frame once threshold is exceeded.
Operation Plasticrateop – – How to apply the plastic rate modification.
Set set
Scale scale
Enable Enableplastichardening – Enable modification of plastic hardening values.
Plastic Hardening Plastichardening – Increase in stiffness as plastic deformation accumulates.
Operation Plastichardeningop – – How to apply the plastic hardening modification.
Set set
Scale scale

Page: Map

Enable Enablestiffmap – Enable attribute-based stiffness mapping.
Stiffness Scale Stiffscalemap – – Scale factor for attribute-driven stiffness (powers of 10).
1e+10 1e+10
1e+9 1e+9
1e+8 1e+8
1e+7 1e+7
1000000 1000000
100000 100000
10000 10000
1000 1000
100 100
10 10
1 1
0.1 0.1
0.01 0.01
0.001 0.001
0.0001 0.0001
0.00001 0.00001
0.000001 0.000001
1e-7 1e-7
1e-8 1e-8
1e-9 1e-9
1e-10 1e-10
Attribute Stiffattr – Primitive attribute to modify stiffness with.
Operation Stiffopmap – – How to modify stiffness with the attribute values.
Set set
Scale scale
Enable Enabledampratiomap – Enable attribute-based damping ratio mapping.
Attribute Dampratioattr – Primitive attribute to modify damping ratio with.
Operation Dampratioopmap – – How to modify damping ratio with the attribute values.
Set set
Scale scale
Enable Enablerestscalemap – Enable attribute-based rest length scale mapping.
Attribute Restscaleattr – Primitive attribute to modify rest length scale with.
Operation Restscaleopmap – – How to modify rest length scale with the attribute values.
Set set
Scale scale
Enable Enableplasticthresholdmap – Enable attribute-based plastic threshold mapping.
Attribute Plasticthresholdattr – Primitive attribute to modify plastic threshold with.
Operation Plasticthresholdopmap – – How to modify plastic threshold with the attribute values.
Set set
Scale scale
Enable Enableplasticratemap – Enable attribute-based plastic rate mapping.
Attribute Plasticrateattr – Primitive attribute to modify plastic rate with.
Operation Plasticrateopmap – – How to modify plastic rate with the attribute values.
Set set
Scale scale
Enable Enableplastichardeningmap – Enable attribute-based plastic hardening mapping.
Attribute Plastichardeningattr – Primitive attribute to modify plastic hardening with.
Operation Plastichardeningopmap – – How to modify plastic hardening with the attribute values.
Set set
Scale scale

Inputs

Input 0 POP – Geometry
Input 1 POP – Constraints
Input 2 POP – Collision Geometry

Outputs

Output 0 POP – Geometry
Output 1 POP – Constraints
Output 2 POP – Collision Geometry