nHair Displacement attributes

This section contains attributes to control the displacement properties of the hair.

Curl

This is the amount of curl displacement applied to each hair. The amount of displacement is relative to the hair width. The Clump Curl creates large scale curls about the clump center, while this attribute creates curls about the direction of individual hairs.

Curl Frequency

This is the rate of curl. Larger values result in more curls. The amount of displacement is relative to the hair width.

Noise Method

Random is good for fuzzy, kinky hair, while the other, smoother noise methods can provide natural shaping and substructure to hair clumps.

Random

Defines the noise as a wiggle for each hair with no relation to neighboring hairs.

Surface UV

Defines the noise displacement volumetrically and is relative to the UV distribution of the hairs across the surface. The noise is a 3D volume with a scale in U and V across the surface with the third dimension (W) mapped down the length of the hairs.

Clump UV

Defines the noise relative to the clump, and while neighboring clumps have completely independent noises, the frequency of the noise is not affected by the surface parametric density.

Noise

This is the amount of perlin noise displacement of the hair. The amount of displacement is relative to the hair width. This can create a knotted, kinky look to the hair.

Detail Noise

The amount of secondary high frequency noise added when the smooth (Surface UV, Clump UV) Noise Methods are used. It can add subtle detail on top of smooth undulations from the base noise. If non-zero, a second noise offset calculation is performed, so this can make evaluation of the hair slightly slower than the smooth noise with no detail noise.

Noise Frequency

This is the spacial scale of the noise offset along hair. Increasing this value results in finer kinks in the hairs.

Noise Frequency U

When the smooth (Surface UV, Clump UV) Noise Methods are used, this attribute scales the noise frequency in the U parameter direction relative to the surface the hair is attached to.

Noise Frequency V

When the smooth (Surface UV, Clump UV) Noise Methods are used, this attribute scales the noise frequency in the V parameter direction relative to the surface the hair is attached to.

Noise Frequency W

When the smooth (Surface UV, Clump UV) Noise Methods are used, this attribute scales the noise frequency along the length of the hair.

Sub Clump Method

Determines how sub-clumps are defined in UV.

Surface UV

The sub-clumps are laid out relative to the overall surface UV space. Some follicles may therefore share a clump with a neighboring follicle. The density of sub-clumps will be affected by the parametric density of the surface the hair system is attached to. The total number of clumps across a surface will be the Num UClumps multiplied by the Num VClumps.

Clump UV

The number of sub-clumps for each clump will be the Num UClumps multiplied by the Num VClumps. All follicles, regardless of clump width, will have the same number of sub-clumps and the width of the sub-clumps will be related to the clump width. With Surface UV the smaller clumps will have fewer sub-clumps and the clump width will be relative to the parametric density of the surface.

Sub Clumping

The amount that secondary clumps pull together. Sub Clumping is useful for a wet look. The clumps are defined in a grid relative to the UV space of the surface the hair is attached to.

Sub Clump Rand

Randomizes the sub-clumps with a noise function. The clumps will get smeared into irregular shapes with higher values.

Num UClumps

The number of sub-clumps in the U dimension of the surface the hair system is attached to.

Num VClumps

The number of sub-clumps in the V dimension of the surface the hair system is attached to.

Displacement Scale

Using a ramp (graph) you can vary the amount of displacement applied from root to tip of the hair clump, affecting Curl, Noise and Sub Clumping.

The left of the graph is the root and the right is the tip. If the left side is zero then the effect will be added gradually—the root position of the hair will not be changed.