Clump Operator
The Clump operator gathers groups of hairs together into distinct clumps, the way real hair forms tufts. You control how clumps are generated, where they sit, and how strongly hairs are drawn toward them. Each clump is defined by a central stem, and when the operator is first added it generates a few clumps automatically so you can see the effect immediately.
How clumping works
Clumping is computed on the hair currently visible in the viewport. Hairs added later - if you raise the hair count, or at render time - are assigned to clumps by following the hairs that were present when the clumps were generated, which act as clump guides. The closest clump guides decide which clump each final hair belongs to.
A practical consequence: the more hairs are visible while you generate and edit clumps, the more precise the clump borders will be. Changing the viewport hair count after clumping does not disturb existing clumps; it only changes the hair used to update the internal clump guides.
Controlling clumps
You can add, remove, and reposition clumps, and adjust how tightly hairs are attracted toward their stems and how that attraction varies along the strand length. Drive the amount with a strand channel or map for natural variation, and limit the operator to part of a groom with a strand group.
Generating clumps
The Clump Creation Method decides where clumps are placed:
- Even - clump centers are spread evenly across the surface, so clumps come out at a consistent size with no bunching and no bare patches. This is the default.
- Random - clump centers are drawn at random from the existing hairs. Clumps vary in size, and some will sit close together while other areas are left without one.
- Guides - one clump per guide, so the guides decide both where clumps sit and what shape their stems take.
- Strand Groups - one clump per strand group of the incoming hair.
- External Clump Strands - clump stems come from a separate set of strands which you can edit on their own.
Clump Count sets how many clumps the Even and Random methods generate; the other methods take their count from whatever they are generated from. Random Seed rearranges the clumps without changing how many there are.
With the Even method, a Distribution Map controls where clumps are allowed: they concentrate in the light areas of the map and are left out of the black ones. The requested clump count is still reached, so masking off part of the surface packs the clumps more densely into what is left rather than producing fewer of them overall.
Braided clumps
The shape of a clump can follow a pattern rather than a simple cone. Combined with the Clump operator, braid patterns turn clumps into procedural braids. See Braid Patterns.
Related
- Braid Patterns - procedural braid shapes for clumps.
- Frizz Operator and Curl Operator - add variation within and around clumps.