High Performance, Art Directable, Hero Cloth Simulation
Carbon Cloth is production proven for simulation of clothing, ropes, nets, chains and deformable skin. When DreamWorks Animation was looking for a new solution to replace their existing Cloth simulation, after extensive internal and market testing they selected Carbon Cloth and first tested it in production on "How to Train Your Dragon 2" where it passed with flying colors. Their experience is reported in this Siggraph 2014 talk Download Here.
Carbon Cloth uses an advanced cloth model to deliver high quality cloth simulation which when combined with robust collision and techniques such as pinch mitigation, supports the very highest quality Hero cloth simulation.
Carbon Cloth was benchmarked by DreamWorks (see Siggraph Talk Download Here), as being upto 60x faster than the competition for Hero Cloth simulation. Highly optimized data and code combined with a multi-threaded design from the ground up, ensures that Carbon Cloth extracts the maximum from your workstation and servers.
Robust Collision handling
Carbon Cloth provides very advanced collision and can handle collision between fast moving objects with ease.
The Carbon Cloth collision supports action AND reaction between:
- Cloth and Character
- Cloth and Cloth as layers
- Cloth and Cloth as self collision within one cloth
- Cloth and Rigid Bodies like buttons
- Cloth and Character skin (where character skin is also a Carbon Morph)
- Cloth and Tetras
- Cloth and Feathers
and also reaction between
- Cloth / Rigid Bodies / Tetras and Velocity Fields (Wind)
By default everything collides with everything else and Carbon Cloth's collision rapidly culls invalid collision objects from the calculation. But its also possible to define who collides with whom, if required.
Various Cloth models
In addition to the Hero Cloth model there is also a faster simpler cloth model for background characters.
Custom models can also be created, for example Chain Mail.
A Tailored Cloth model supports panel based garments and allows anisotropic properties in the warp and weft directions to be defined. More information here.
A cornerstone of Carbon Cloth is its art directability, giving the artist the features and tools they need to create great cloth simulations. Almost all attributes can be animated and most attributes support paint map control.
The Carbon Cloth collision is also very robust, but sometimes you want it to be more forgiving, so there is also the option to relax the collision for specified colliders. This is allows for interpenetration of body parts with the cloth (for example when they are out of shot) or when you are just not going to render the body part anyway (for example knees poking through a pair of trousers).
Some creases are meant to be permanent. Typical cases for this include curtains, dress shirts with collars, skirts with pleats or pants with pleats. Carbon allows to paint areas where such a behavior is wanted and overwrites all start and reference angular information to ensure permanent creasing.
Creating permanent creases for pants.
Goal shape control
The Goal Skin is an attribute that describes the strength of the skinning constraint between the Goal Pose and the current cloth pose.
The Goal Skin can also be used to describe the nature of each individual node, from fully dynamic to dynamic and constrained and finally kinematic and constrained (pure animation). Kinematic nodes do not generate collision with other kinematic objects.
An advanced use of Carbon Cloth is the use of the Carbon Morph node to create a deformable skin for a character. This has been used in many situations from pinch mitigation under the armpits and between the legs, to deforming the points on a dinasour head while the hand strokes over them to deforming the belly of a creature when pressed by the arms and legs to squash and stretch of the body to deforming the ground when something lands on it. Read more about Carbon Morph here.
A selection of analysis tools are provided to allow inspection of the character to identify an areas of pinching, and inspection of the cloth to identify any geometry corruption.
Carbon Cloth can accept tri-mesh, quad-mesh and even non-manifold geometry.
Garments can be simulated from their import rest state or they can be simulated from the panels that were used to create them using the Tailored model). This allows the easy import garments from garment creation packages such as Marvelous Designer. Wrinkles from the imported rest shape can be maintained, limited in angle or removed.
Volume based cloths using Tetrahedrons are also supported with the additional Carbon Tetra node.
Carbon provides the interface for Drag, Skin Drag and Lift aerodynamics parameters on all relevant scene nodes. The Houdini plug-in supports the following wind / flow sources:
- Uniform field
- Houdini vector field
- OpenVDB velocity fields
- Crease hysterisis
- Garment construction support