Carbon Cloth¶
Description¶
This object node defines a cloth simulation object, its import geometry, and the cloth parameters.
Inputs¶
Input #1 - Start Geometry
Start mesh.
Note
While the Start Mesh input geometry may be animated, the Carbon Cloth will only read the geometry at the Simulation Start Frame.
Input #2 - Reference Geometry
Optional Reference Mesh.
The reference metrics allow the cloth to simulate based on physically correct metrics, no matter what the metrics in the start mesh might be.
Note
When no reference mesh is specified, the start pose geometry is also used as the reference pose.
Input #3 - Goal Geometry
Optional Goal Mesh.
The goal pose allows the cloth to match the specified pose during the simulation.
The goal pose geometry is usually used animated, or enabled for a short period of time through the Skin strength parameters.
If no Goal Mesh is set, all Goal Skin parameters are grayed out and cannot be edited.
Note
The goal pose geometry needs to respect the same topology as the one found on the reference pose.
See also
Parameters¶
Carbon Node Name carbonNodeName
The name of the Carbon node that will be spawned internally. This name can be different from the UI node, and will be used for constraints or filters.
Activation activation
Enable this object. Use 0 to disable, any other value to enable.
Stasis stasis
Tick to place this object into stasis mode. Can be animated.
Stasis Mode triggers a dynamics integration that ignores all action forces and wipes out all kinetic energy, reducing motion and deformation to only result from the reaction forces generated by constraints, such as collision, joints, or soft body primitives.
Note
If the Carbon Simulation’s Lead Simulation parameter Stasis Mode is toggled on, this node will also be in Stasis mode during the Lead Simulation, even if this node’s Stasis parameter is toggled off.
Cloth Model clothModel
There are 3 pre-set material models available:
Face-Segment-Crease: Has angular, edge and area preservation constraints.
Tailored: An extension of Face-Segment-Crease, introducing anisotropy through the support of different parameter settings for Weft, Warp, and Bias.
Note
Tailored cloth model only works with triangle geometry!
Segment-Crease: Faster as it only has edge and angular controls.
Note
Choose the material model that translates best into how you want your mesh to physically behave. Choosing the model defines how and where the cloth will bend and deform.
Cloth Material
Material material
Select a Carbon Cloth Material. This Material will be used to apply cloth attribute values to and read from.
From Material
Click to apply cloth attribute values from the selected Carbon Cloth Material onto this Cloth node.
To Material
Click to apply cloth attribute values from the this Cloth node onto the selected Carbon Cloth Material.
Status status
Status messages.
Use Material useMaterial
Tick to directly use the selected Material for this Cloth. All parameters that are controlled by the Material are hidden when enabled.
Collision
Activated collisionActivated
Untick this box to remove all collision between this Cloth and itself and all other Carbon nodes in the same simulation.
If unticked, all other Collision parameters will be disabled, as well as all Collision Material and Aerodynamics parameters.
Note
- A Cloth without collision activated cannot act as parent node in a Carbon Binding constraint.
- A Cloth without collision activated cannot interact with any Carbon Flow nodes.
Edge Collision edgeCollision
Tick this box to change the cloth collision model from primitives to edges.
Primitive Group groupA
Selection of primitives that are used for collision.
Note
- Collision can only be set to Primitive Group, or Edge Group, not a combination of both.
- This parameter is optional.
- If left empty or set to *, all primitives of the Start Mesh will be used.
- This parameter is only available if collision is activated. See Activated.
- This parameter is only available if Edge Collision is unticked.
Edge Group groupA
Selection of edges that are used for collision.
Note
- Collision can only be set to Edge Group, or Primitive Group, not a combination of both.
- Cannot be empty.
- If set to *, all edges of the Start Mesh will be used.
- This parameter is only available if collision is activated. See Activated.
- This parameter is only available if Edge Collision is ticked.
Thickness thickness
Thickness of the cloth. In scene units.
See also
Note
This parameter is only available if collision is activated. See Activated.
Self Collide selfCollide
Enable self-collision for this cloth against itself.
Note
This parameter is only available if collision is activated. See Activated.
Use Self Thickness useSelfThickness
Tick to use a Self Thickness for self-collision for this cloth. If left unticked, the Thickness value will be used for Self Thickness. In scene units.
See also
Note
This parameter is only available if collision is activated. See Activated.
Self Thickness selfThickness
Self Thickness of the cloth. In scene units.
See also
Note
This parameter is only available if collision is activated. See Activated.
Reference
Animated Metrics metricsAnimated
Enable animated reference geometry metrics by evaluating and updating the reference lengths at every frame.
Animated Angles anglesAnimated
Enable animated reference geometry angles by evaluating and updating the reference angles at every frame.
Angle Threshold flatAngle
The angle is measured in degrees; therefore, the range of this value is 0-180.
When using the Face-Segment-Crease, or the Segment-Crease model: Angular threshold to override the reference geometry crease angles with flat angles. Reference crease angles found below this threshold value will be replaced by flat angles. At a value of 0, none of the existing angles will be overwritten, whereas a value of 180 will force the use of flat angles for the complete cloth.
When using the Tailored model: Angular threshold to set the tailored seaming angles to flat angles. Seaming angles found above this threshold value on the start pose geometry will be set to their respective start pose angles. At a value of 0, none of the existing start pose angles will be overwritten, whereas a value of 180 will force the use of flat angles for the complete cloth.
Wrinkles Limit wrinklesLimit
Painted point attribute name: wrinkles
Wrinkle angular limit applied to the wrinkle painted attribute map. The default value is 180 degrees. Using a negative value will reverse the map.
Reference Blend
Blended Reference blendedReference
Tick to enable blended reference between start and reference pose.
Base Parameters
Reference Blend referenceBlendBase
Reference blend.
Allows for blended reference between start and reference pose.
Range Parameters
Reference Blend referenceBlendRange
Painted point attribute name: referenceBlend
The multiplier of the painted point attribute values that add up to the base parameter.
Density
Animated densityAnimated
Enable animated parameters for this section by evaluating and updating the values at every frame.
Note
It’s good practice to leave this toggled off
when not using
animated parameters because it impacts performance.
Base Parameters
Density densityBase
Cloth density.
Unit in \(kg/m\) when using Segment-Crease model.
Unit in \(kg/m^2\) when using Face-Segment-Crease or the Tailored model.
Range Parameters
Density densityRange
Painted point attribute name: density
The multiplier of the painted point attribute values that add up to the base parameter.
Stretch
Animated stretchAnimated
Enable animated parameters for this section by evaluating and updating the values at every frame.
Note
It’s good practice to leave this toggled off
when not using
animated parameters because it impacts performance.
Base Parameters
Stiffness stretchStiffnessBase
Cloth stretch stiffness (\(mass/time^2\)).
See also
Viscosity stretchViscosityBase
Cloth stretch viscosity (dimensionless).
See also
Compression stretchCompressionBase
Cloth stretch compression, must be strictly greater than 0 and always be smaller than or equal to extension.
See also
Extension stretchExtensionBase
Cloth stretch extension, must be strictly greater than 0 and always greater than or equal to compression.
See also
Equilibrium stretchEquilibriumBase
Cloth stretch resting length (equilibrium) as a ratio of the reference length.
Use 1 for the default resting length.
See also
Range Parameters
Stiffness stretchStiffnessRange
Painted point attribute name: stretchStiffness
The multiplier of the painted point attribute values that add up to the base parameter.
Viscosity stretchViscosityRange
Painted point attribute name: stretchViscosity
The multiplier of the painted point attribute values that add up to the base parameter.
Compression stretchCompressionRange
Painted point attribute name: stretchCompression
The multiplier of the painted point attribute values that add up to the base parameter.
Extension stretchExtensionRange
Painted point attribute name: stretchExtension
The multiplier of the painted point attribute values that add up to the base parameter.
Equilibrium stretchEquilibriumRange
Painted point attribute name: stretchEquilibrium
The multiplier of the painted point attribute values that add up to the base parameter.
Weft Warp Bias Factors
Stiffness stretchStiffnessWeft
stretchStiffnessWarp
stretchStiffnessBias
The weft and warp and bias factors that allow for anisotropy when set to unequal values.
Note
This parameter is only accessible when using the Tailored model.
Equilibrium stretchEquilibriumWeft
stretchEquilibriumWarp
stretchEquilibriumBias
The weft and warp and bias factors that allow for anisotropy when set to unequal values.
Note
This parameter is only accessible when using the Tailored model.
Bend
Animated bendAnimated
Enable animated parameters for this section by evaluating and updating the values at every frame.
Note
It’s good practice to leave this toggled off
when not using
animated parameters because it impacts performance.
Base Parameters
Stiffness bendStiffnessBase
Cloth angular stiffness (\(mass * length^2 / time^2 / degree\)).
See also
Yield bendYieldBase
Cloth angular yield (\(degree\)), between 0 and 180.
See also
Plasticity bendPlasticityBase
Cloth angular plasticity, between 0 and 1.
See also
Limit bendLimitBase
Cloth crease angular limit (\(degree\)), between 0 and 180.
See also
Range Parameters
Stiffness bendStiffnessRange
Painted point attribute name: bendStiffness
The multiplier of the painted point attribute values that add up to the base parameter.
Viscosity bendViscosityRange
Painted point attribute name: bendViscosity
The multiplier of the painted point attribute values that add up to the base parameter.
Yield bendYieldRange
Painted point attribute name: bendYield
The multiplier of the painted point attribute values that add up to the base parameter.
Plasticity bendPlasticityRange
Painted point attribute name: bendPlasticity
The multiplier of the painted point attribute values that add up to the base parameter.
Limit bendLimitRange
Painted point attribute name: bendLimit
The multiplier of the painted point attribute values that add up to the base parameter.
Weft Warp Bias Factors
Stiffness bendStiffnessWeft
bendStiffnessWarp
bendStiffnessBias
The weft and warp and bias factors that allow for anisotropy when set to unequal values.
Note
This parameter is only accessible when using the Tailored model.
Surface
Animated surfaceAnimated
Enable animated parameters for this section by evaluating and updating the values at every frame.
Note
- It’s good practice to leave this toggled
off
when not using animated parameters because it impacts performance. - This parameter is only accessible when using the Face-Segment-Crease or the Tailored model.
Base Parameters
Compression surfaceCompressionBase
Cloth surface compression, must be strictly greater than 0 and smaller than or equal to extension.
Note
This parameter is only accessible when using the Face-Segment-Crease or the Tailored model.
See also
Extension surfaceExtensionBase
Cloth surface extension, must be strictly greater than 0 and greater than or equal to compression.
Note
This parameter is only accessible when using the Face-Segment-Crease or the Tailored model.
See also
Pressure surfacePressureBase
Unit in \(mass/length/time^2\).
Describes the force per area over a surface exercised by a virtual fluid.
Warning
Explicit force, so high values can produce instability.
Note
This parameter is only accessible when using the Face-Segment-Crease or the Tailored model.
See also
Range Parameters
Compression surfaceCompressionRange
Painted point attribute name: surfaceCompression
The multiplier of the painted point attribute values that add up to the base parameter.
Note
This parameter is only accessible when using the Face-Segment-Crease or the Tailored model.
Extension surfaceExtensionRange
Painted point attribute name: surfaceExtension
The multiplier of the painted point attribute values that add up to the base parameter.
Note
This parameter is only accessible when using the Face-Segment-Crease or the Tailored model.
Pressure surfacePressureRange
Painted point attribute name: surfacePressure
The multiplier of the painted point attribute values that add up to the base parameter.
Note
This parameter is only accessible when using the Face-Segment-Crease or the Tailored model.
Viscous Damping
Animated viscousDampingAnimated
Enable animated parameters for this section by evaluating and updating the values at every frame.
Note
It’s good practice to leave this toggled off
when not using
animated parameters because it impacts performance.
Base Parameters
Viscous Damping viscousDampingBase
Cloth viscous damping (\(1/time\)), damping control over the nodes’ group cohesion. While the viscous damping does not affect the kinetic energy of the cloth, it globally constrains all the nodes to have velocities aligning with the barycentric velocity of the cloth. This term is extremely powerful considering that it is capable of dissipating local vibrations and error terms.
See also
Range Parameters
Viscous Damping viscousDampingRange
Painted point attribute name: viscousDamping
The multiplier of the painted point attribute values that add up to the base parameter.
Velocity Reducer
Animated reducerAnimated
Enable animated parameters for this section by evaluating and updating the values at every frame.
Note
It’s good practice to leave this toggled off
when not using
animated parameters because it impacts performance.
Base Parameters
Reducer reducerBase
Cloth velocity reducer. Ranges from 0 to 1, where a value of 0 has no effect and 1 removes 100% of the vertex velocity.
Range Parameters
Reducer reducerRange
Painted point attribute name: reducer
The multiplier of the painted point attribute values that add up to the base parameter.
Forces
Animated forcesAnimated
Enable animated parameters for this section by evaluating and updating the values at every frame.
Note
It’s good practice to leave this toggled off
when not using
animated parameters because it impacts performance.
Base Parameters
Forces forcesBase
Cloth forces.
Unit in \(Newton\).
Warning
- Continually applying forces produces infinite acceleration.
- The effect of forces is proportional to the mass of the objects / nodes they are applied to.
Range Parameters
Forces forcesRange
Painted point attribute name: force
The multiplier of the painted point attribute values that add up to the base parameter.
Collision Material
Note
This section is only available if collision is activated. See Activated.
Animated materialAnimated
Enable animated parameters for this section by evaluating and updating the values at every frame.
Note
It’s good practice to leave this toggled off
when not using
animated parameters because it impacts performance.
Static Friction staticFriction
Cloth’s static friction, greater than or equal to 0 and greater than or equal to dynamic friction.
See also
Dynamic Friction dynamicFriction
Cloth’s dynamic friction, greater than or equal to 0 and smaller than or equal to static friction.
See also
Aerodynamics
Note
This section is only available if collision is activated. See Activated.
Warning
Aerodynamics / Carbon Flow does not currently work properly with Carbon Simulation Simulation Space. When using Aerodynamics in a Carbon Simulation that has a non-default Simulation Space, it will neither take the Simulation Space’s transform, nor its local velocity from the animation into account.
Animated aerodynamicsAnimated
Enable animated parameters for this section by evaluating and updating the values at every frame.
Note
It’s good practice to leave this toggled off
when not using
animated parameters because it impacts performance.
Base Parameters
Form Drag formDragBase
Aerodynamics form drag. Shapes with a large apparent cross section exposed to the air flow and with a high form drag coefficient will receive more drag than thinner ones.
Warning
Explicit force, so high values can produce instability.
See also
Skin Drag skinDragBase
Aerodynamics skin drag. Friction of the skin against the air flow. Usually much smaller, and never bigger than form drag.
Warning
Explicit force, so high values can produce instability.
See also
Lift liftBase
Aerodynamics lift. Lift force coefficient.Aerodynamic force that is perpendicular to the direction of the oncoming air flow.
Warning
Explicit force, so high values can produce instability.
See also
Range Parameters
Form Drag formDragRange
Painted point attribute name: formDrag
The multiplier of the painted point attribute values that add up to the base parameter.
Skin Drag skinDragRange
Painted point attribute name: skinDrag
The multiplier of the painted point attribute values that add up to the base parameter.
Lift liftRange
Painted point attribute name: lift
The multiplier of the painted point attribute values that add up to the base parameter.
Goal Skin
If no Goal Pose is set, all Goal Skin parameters are grayed out and cannot be edited.
Enable Goal Pose enableGoalPose
Enable/disable the goal posing without having to remove the connection to Goal Mesh. If disabled, all Goal Skin parameters are grayed out and cannot be edited.
Animated Goal Pose goalPoseAnimated
Enable animated goal pose geometry by evaluating and updating the position targets at every frame.
Animated Goal Skin goalSkinAnimated
Enable animated parameters for this section by evaluating and updating the values at every frame.
Note
It’s good practice to leave this toggled off
when not using
animated parameters because it impacts performance.
Velocity Limit goalSkinVelocityLimit
The maximum relative velocity between a simulated and animated node.
Base Parameters
Viscosity goalSkinViscosityBase
The goal skin viscosity to cope with fast moving motions.
Viscous behavior between a node and its animation.
Range Parameters
Strength goalSkinStrengthRange
Painted point attribute name: goalSkinStrength
The multiplier of the painted point attribute values that add up to the base parameter.
Viscosity goalSkinViscosityRange
Painted point attribute name: goalSkinViscosity
The multiplier of the painted point attribute values that add up to the base parameter.
Lower Threshold
Strength goalSkinLowerThreshold
The strength threshold below which a node is not skin constrained. The value for this attribute ranges from 0 to 1, interpolating between the lowest and the highest possible goal skin strength (taking both the base and the painted parameter into account).
See also
Upper Threshold
Strength goalSkinUpperThreshold
The strength threshold above which a skinned node becomes kinematic and animated. The value for this attribute ranges from 0 to 1, interpolating between the lowest and the highest possible goal skin strength (taking both the base and the painted parameter into account).
See also
Physics Draw¶
Physics Draw physicsDraw
This dropdown menu provides different drawing options.
See also
Use Color useColor
Tick to enable custom color for the Physics Draw.
Color colorr
colorg
colorb
Custom color for the Physics Draw.
Draw Goal drawGoal
Tick to enable drawing of the goal pose Physics Draw.
Note
This parameter is only available if Enable Goal Pose is ticked.
Import & Export¶
Import Velocity importVelocity
Tick this box to enable reading initial velocities for this cloth from the
Start Mesh velocity
vector array
attribute, if there is one.
Export Velocity exportVelocity
Tick this box to enable exporting the velocities for this cloth to the
output mesh as velocity
vector array attribute.
These can then be used as input for another cloth simulation, when enabling
Velocity Import for that cloth.
Bend Stress bendStress
Tick this box to export the cloth Bend Stress.
Stretch Stress stretchStress
Tick this box to export the cloth Stretch Stress.
Surface Stress surfaceStress
Tick this box to export the cloth Surface Stress.