Digital Tutors: nCloth Techniques for Characters in Maya
nCloth has been a really sleek way to simulate cloth effects in CG. Here are some tips worth checking out from Digital Tutors.
1) Check the animation to see if there are already inner penetration occuring, and fix those first.
2) Set “Space Scale” in nucleus attribute to 0.01 to match the cm default unit.
3) We can always let the ncloth simulation play a little to set the initial state so we get the shape and weight of cloth to what we want.
4) Tweak dynamic properties of ncloth, especially stretch and compression resistance to simulate something less stretchy than the default.
5) Thickness (under collisions) is useful for solving penetration problems, both for the rigid body and cloth.
6) Presets are good ways to start!
7) Use nCache to preview simulations, and use playblasts for more accurate previews. Delete cache when you need a new one.
8) Friction and stickiness prevents sliding, while damp makes it lose energy faster (sometimes we need to decrease this if it comes to rest too slow).
9) In quality settings, Push Out may help to solve crunching of cloth (use sparingly). Increase max self collide iterations (to something like 40) makes the simulation really nice.
10) In nucleus, we can also up the substeps and iterations to 40 20 respectively (for example) for better quality.
11) For point to surface constraint, select the vertices of the cloth object, then the mesh to constraint to. Constraint method is also essential.
12) For things like jeans, we might want to consider duplicating it, skin it, copy weights from body mesh to the jeans, then do a point to surface constrain on this duplicate instead of directly constraining to the body. Make sure the duplicate is not set to collide.
13) Sometimes we can use blend shapes on the body to correct inner penetration problems seen by the camera. Duplicate the body, shift it out to one side. Add the blend shape deformer to the body and make sure the deform order is right before skin. Set the deformer value to 1 and start animating the vertices by sculpting (soft select).
From what I know, feature film VFX companies does the simulation on super dense meshes to get really nice folds, even though the cloth mesh rendered may not be that high.