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grossoftimage
02-06-2007, 08:07 PM
what attribute controles the stifness of the ncloth pressure (volume tracking model) . for example the bouncing of a character belly but without inflating the surface? I tried with the start presure but this inflates the surface .


thanks and bye
note: sorry for my english

Duncan
02-07-2007, 07:38 PM
There are many different ways to go about it, depending on the desired behavior. The pressure models an internal gas, which does not have stiffness directly. However you can add things like damp or deform resistance to keep the material from jiggling very much. (beware that damp, unlike deform resistance, will resist overall rotation of the mesh) There is also a pressure damping attribute that you may find useful.

Also one could parent or bind skin the original input mesh to the character's skeleton, then use "inputMeshAttract" to attract to this base position (one can also paint the inputMeshAttract values to only allow some parts to jiggle ).

One could also select the cvs on the belly and constraint them in different ways. The simplest is a transform constraint, with the transform parented to the base character( this is similar to using input mesh attract ). One can use slide on surface constraints to model a type of fat layer.. the friction and various strength attributes on the constraint can be edited to create a wide range of behaviors.

Bend/stretch/Compression stiffness can be combined with the volume conservation to stiffen the overall motion. Another way to stiffen the mesh would be to create a component to component constraint for the cvs of the mesh and use the max distance setting on the constraint to create internal cross links. These links can be like springs, but you could also use the motion drag attribute on the constraint, lowering the strength attribute, so that the links tend more to drag the points around rather than preserve a specific distance. This in a sense would model internal "guts" that can deform over time but resist changing shape. However I'm guessing the effect would not be too different from simply using deform resistance on the cloth.

Duncan

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