vellum

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vellum

vellum cloth:

• breaking and tearing
• paneling and draping
• cloth simulation
• low res and high res cloth
• quick moving cloth

vellum softbodies

• balloon, strut, tetrahedral, fiber

friction

• Vellum Solver SOP: static threshold -> @friction, dynamic scale -> @dynamicfriction

plasticity

• objects return to rest shape unless plasticity enabled eg. for hair or grass which gets pressed down
• enable plasticity in Vellum Constraints node

collisions

• POP Collision Ignore or SOP Attribute Wrangle to enable / disable collisions

dynamic constraints

• Vellum Constraints with Vellum Solver, wired up to force_output for dynamic constraints

sliding constraints

• eg. constrain to nearest point on primitive (not same point across time) for stitching

64-bit solve setup

• change precision with Attribute Cast SOP before Vellum Configure Cloth

tips

• santity-check pscale by showing thickness using Vellum Solver SOP's visualize tab
• spead vs quality: substeps, constraint iterations, collision passes, post collision passes
• too stretchy and not converging? increase constraint iterations (cheaper than substeps)
• protrusion problems? (sharp point colliding with high res cloth only deforms local) increase collision passes or substeps
• failed collision? 1. make cloth thicker (but NOT thicker than edge lengths!) 2. increase substeps for high res cloth 3. increase post collision passes 4. layer numbers for stacked cloth (higher layers act lighter)
• asymmetric solve? increase smoothing iterations
• unruly object? possibly self-intersections if pscales to large - can use plasticity to set final configuration to initial rest pos. If not converging (especially pressure and struct constraints), increase smoothing iterations, damping and sort contraints randomly
• unstable pins? (strong bend constraints and hard pins) use soft constraints and more smoothing iterations
• restarting sims? (using output of a previous sim as a starting point) be careful to properly setup attributes - see docs
• collisions not working? check docs for what is used as a collider for each geometry type
• crinkled cloth? restage closer to origin or use 64-bit solve

attributes

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attributes

@attr1

@attr2

@attr3

@attr4

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dop_nodes

Vellum Constraint Property Modifies common Vellum Constraint properties during a Vellum solve.

Vellum Constraints Microsolver to create Vellum constraints during a simulation.

Vellum Object Creates a DOP Object for use with the Vellum Solver.

Vellum Rest Blend Blends the current rest values of constraints with a rest state calculated from the current simulation or external geometry.

Vellum Solver Sets and configures a Vellum solver.

Vellum Source A Vellum node that creates Vellum patches.

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shelf_nodes

Surface Collider Create a Static Object from SOP Geometry pre-configured for interaction with cloth.

Vellum Cloth Configures vellum cloth from geometry and adds to current vellum simulation.

Vellum Hair Configures vellum hair from geometry and adds to current vellum simulation.

Vellum Strut Softbody Configures Vellum strut softbody from geometry and adds to current Vellum simulation.

Vellum Tetrahedral Softbody Tetrahedralizes input geometry, configures it as a Vellum softbody, and adds it to current Vellum simulation.

Vellum Balloon Configures vellum balloon from geometry and adds to current vellum simulation.

Vellum Grains Configures vellum grains from geometry and adds to current vellum simulation.

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sop_nodes

Vellum Configure Grain Configures geometry for Vellum Grain constraints.

Vellum Configure Hair ?

Vellum Configure Strut Softbody ?

Vellum Configure Tetrahedral Softbody ?

Vellum Constraints Configure constraints on geometry for the Vellum solvers.

Vellum Drape Vellum solver setup to pre-roll fabric to drape over characters.

Vellum I/O Packs Vellum simulations, saves them to disk, and loads them back again.

Vellum Pack Packs Vellum geometry and constraints into a single geometry.

Vellum Post-Process Applies common post-processing effects to the result of Vellum solves.

Vellum Reference Frame Ties vellum points to a reference frame defined by moving geometry.

Vellum Rest Blend Blends the current rest values of constraints with a rest state calculated from external geometry.

Vellum Solver Runs a dynamic Vellum simulation.

Vellum Stitch Points ?

Vellum Struts ?

Vellum Unpack Unpacks a Vellum simulation into two outputs.

Vellum Weld Points ?

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