2022-11-24 Procedural Hair for Blender 3.5

Procedural Hair

November 24, 2022

As a follow up of the last module meeting Daniel Bystedt organized a meeting to find the priorities (nodes and node groups) for procedural hair for Blender 3.5.

Present:

  • Andy Goralczyk
  • Dalai Felinto
  • Daniel Bystedt
  • Jacques Lucke
  • Lukas Tonne

The topics are in order of priority (from higher to lower):

  • Distribute child splines on faces
  • Hair info
  • Clump splines
  • Hair frizz
  • Curl hair
  • Smooth hair
  • Braids
  • Push hair outside surface
  • Rotate hair
  • Bend hair
  • Straighten hair
  • Shrinkwrap hair
  • Interpolate shape

Feedback:

  • Distribute child curves on faces
    • This is the basic interpolation needed for working with parent/child hair workflow.
  • Hair info
    • Should be a node group if possible, before becoming a built-in node
  • Clump splines
    • Parting should be doable via attributes within a data-set.
    • The clump criteria (e.g., distance) should be an option for the node.
    • Geodesic distance node would help, ahtough slow
  • Hair frizz
    • Keeping the distance between segments is needed regardless.
      • It can be one of the building blocks for the hair frizz group.
  • Curl hair
    • The frequency, amplitude and length should be inputs that can be mapped.
    • The total length of the curly hair is important in some cases (to preserve the hair length).
  • Smooth hair
    • It doesn’t try to align the hair tip with the surface.
    • Preserve the overall length or;
    • Lock the being/end of the curves.
    • Use case/example:
      • If you have a lot of frizz, Daniel would randomly select hair and smooth them out, so it gets a less uniform look.
      • It helps for final tweaks without having to do changes on the begin of a node-tree (before the frizz is applied).
  • Braids
    • Braids and corn rows can use the same system.
  • Push hair outside surface
    • This is one of the most complicated and important topics.
    • This can be computational expensive.
    • A generic solution may be tricky, but a simple system may be possible for some use cases.
  • Rotate hair
    • Spin the hair around the root around the surface normal.
    • Useful to get random overlaps.
  • Bend hair
    • The simple case is to bend long hair tips.
    • Nice for moustaches (not french mustaches).
    • For long hair the root point is not relevant.
    • It may be better to pick a few of the last control points, but it is also dependent of the control point density.
  • Shrinkwrap hair
    • Useful for some animals, where the hair gets really close to the legs.
  • Interpolate shape
    • Useful for animating art-directed hair poses.
  • Straighten hair
    • Same as the puff brush.
32 Likes

excited to see the development on this, can’t wait to see what else is cooking for grooming!

See @DanielBystedt posts on Twitter. He did some interesting node groups / proof of concept :slight_smile:

https://twitter.com/3DBystedt/status/1612235936334581761?s=20&t=_LIyMEq9l0TjNT9_5RfHcQ