Been doing a few fur tests lately with the pig head. My usual process is to grow guides, set direction to -Z, grow hairs. Works for a quick setup, but if you display the skin and hairs, you can see a lot of the hair has been pushed under the skin surface.



From browsingthe fur shelf it looks like a guide process ‘lift’ should fix this, and for the most part it does if you set lift to about 0.3:



However taking a closer look at the bottom of the ears its pretty messy, there's quite a lot of hair under the surface still:



Found the ‘guide collide with vdb’ sop, its good, but a bit heavy handed; if I raise the values high enough to fix the ingrown hairs, the rest of the groom goes too puffy, losing the slicked down groom feel:



Going back to the original set direction, if I do a bit of prep work and use a measure sop to get the x-gradient, and use that as fur direction for the ears, everything behaves much better:



But the nose still has issues, clearly regions that point in the opposite direction to the overall fur direction of -Z has problems. More to the point, zooming in on the corner of the nose you can see the hairs don't conform well to the surface of the skin, and neither the lift sop nor guide_collide_with_vdb sop do much to help:



So apart from hand grooming, is there a better way to effectively slick down the hairs to the skin?

My test pig groom is attached…. (last entry in the attachments list below)



-matt

Attachments:
set_direction_goes_under_surface.PNG (79.3 KB)
lift_0_3.PNG (36.5 KB)
hair_under_ear.gif (802.0 KB)
guide_collide_vdb.gif (610.0 KB)
furdirection.gif (37.6 KB)
nose.gif (350.3 KB)
fur_slick.hip (509.9 KB)

Its rather straight forward using the Curve Advect tool and drawing the curves the guides should align to. There is a Surface Lift parm on the Volume Velocity from Curves that defaults to 0.5 or something. Might want to set that to 0. The Voxel Scale parm can also be lowered to get the guide closer.

Attachments:
bryl.hip (585.3 KB)

Attachments:
fur_slick_02.hip (790.2 KB)

Attachments:
fur_slick_02.hip (581.7 KB)
fur_slick_v02.gif (148.0 KB)

Here is an alternative way to set the initial guide direction with two sets of guides. One set (guide guides if you like) with low density that sets the direction for the advection of the main guides.
Guide guides:
Main guides advected by the guide guides:

Not sure why you do all the peak in/out stuff at the end there. Isnt a singel minpos() sufficient to get all the guides glued to the skin? Might be missing something though.

-b

Attachments:
fur_slick_03.hiplc (630.3 KB)

Attachments:
sleak_hair_clean.hiplc (440.3 KB)
piggy.png (725.6 KB)