Clump Hair Curves¶
The Clump Hair Curves node gathers nearby hair curves together around designated guide curves, creating clump formations commonly seen in real hair, fur, and grass. It is a key step in grooming workflows for adding realism and structure by simulating how strands naturally group due to moisture, product, or physical interaction.
Inputs¶
- Geometry
The input geometry containing the hair curves to be clumped.
- Factor
Controls the overall strength of the clumping effect. A value of 0.0 applies no clumping, while 1.0 fully pulls curves toward their guides.
- Shape
Defines how the clumping influence changes along the length of each curve. A value of 0.0 applies a constant strength, while 0.5 results in a linear falloff from root to tip.
- Tip Spread
Adds random variation to the positions of curve tips, preventing perfect convergence and helping clumps look more natural.
- Clump Offset
Applies a random directional offset to entire clumps, introducing subtle variation between groups.
- Distance Falloff
Defines how the influence of each guide curve decreases with distance. A value of 0.0 disables distance-based falloff, making all nearby curves equally affected.
- Distance Threshold
Sets the maximum distance from a guide at which clumping has an effect. Curves farther than this threshold will not be influenced by that guide.
- Seed
Controls the randomization used for offsets and variation. Changing this value alters the random distribution of clumping while keeping the same parameters.
- Preserve Length
When enabled, maintains the original length of each curve during deformation. When disabled, curves may stretch or shrink slightly as they are pulled toward guides.
Guide Map¶
- Guide Index
A map that specifies which guide curve acts as the center for each clump. If provided, this takes priority over any existing
guide_curve_indexattribute, and the Guide Distance and Guide Mask inputs are ignored.- Guide Distance
The minimum distance between selected guide curves when generating a new guide map. Larger values produce fewer, larger clumps.
- Guide Mask
Defines which curves can be used as guides during automatic guide map creation.
- Existing Guide Map
When enabled, uses the existing guide map attribute if it is already available. If disabled and Guide Index is not provided, a new guide map is generated using Guide Distance and Guide Mask. Creating the guide map separately allows for finer control over guide placement and grouping.
Outputs¶
- Geometry
The resulting geometry with clumped hair curves.
Guide Map¶
- Guide Index
The guide index map used for this operation. If a new guide map was generated by this node, it is stored and provided through this output for reuse in subsequent operations.