Tuesday, July 8, 2014

Tip: add eye lashes to face rig in Maya


Today, i was trying to add eye lashes to a face i was working on.  first i tried wrapping the entire eye lash to the head but found when eyelid opened that the part of eyelash away from head wasn't moving with the inner part of brow.  So i used Michael Bazhutkin's (rivet.mel) to get some locators following the eye lash and i skinned these to eye lash.  The result was the wrapped inner eye lashes followed eyelid opening precisely and the outer eyelash followed eye lids roughly via the skinning.  Here are a couple of images of the process i used (there may be many better other approaches different rivet methods, custom nodes ...).

First i needed to make an eye lash.  Because i wanted eye lash to follow head exactly i actually started from an edge of the head then extruded it out:

Then i went about the technical stuff first picking a couple edges of the head to create rivets for outer eye lashes:

Finally i wrapped the eye lash to the head but made sure to exclude the outer eyelash from the wrap deformer via the paint set membership tool with remove (a script may be helpful to remove or add vertices to a wrap set) (also an advantage of modeling eye lash from head, we can use a small max distance to get inner eye lash following head):

(for skinning eye lash to rivet, i weighted all eye lash to root, then used add influence of all rivets with default settings and max 2 influence per vert ( weighting to a duplicate joint following rivet would be more helpful if wanted to allow shaping of eye lash)
finally some future tool ideas i was thinking of:
-- mirror creases across mesh
-- mirror selected material across mesh
-- add or removal of selected vertices from a wrap set
--- go from a corrective shape to a model we can edit and back and forth

Hope this was helpful,

Inspired by,
Michael Bazhutkin (his rivet online tool worked really well for making the outer eye-lash follow head)

i ended up not using the rivet for the outer vertices of eyelash because of flipping of vertices causing the rivets to flip and hence the outer eye lash.  so i ended up duplicating the upper eyelid joint and skinning that to just the outer vertices of eye lash.  Then i used a constraint to get this joint following the eyelid joint.  and with a little weight painting tweaking, the eye lash was opening in a more stable way.