Children

Reference

Panel:Particle System ‣ Children

Children are Hair and Keyed particles assigned subparticles. They make it possible to work primarily with a relatively low amount of Parent particles, for whom the physics are calculated. The children are then aligned to their parents. Without recalculating the physics the number and visualization of the children can be changed.

Children can be emitted from particles or from faces (with some different options). Emission from Faces has some advantages, especially the distribution is more even on each face (which makes it better suitable for fur and the like). However, children from particles follow their parents better, e.g. if you have a soft body animation and do not want the hair to penetrate the emitting mesh. But see also our manual page about Hair.

If you turn on children the parents are no longer rendered (which makes sense because the shape of the children may be quite different from that of their parents). If you want to see the parents additionally turn on the Parents button in the Visualization panel.

Children carry the same material as their parents and are colored according to the exact place from where they are emitted (so all children may have different color or other attributes).

The possible options depend from the type of particle system, and if you work with Children from faces or Children from particles. We do not show every possible combination, only the settings for a Hair particle system.

Options

Child Type

None

No Children are generated.

Simple

Children are emitted from the parent position.

Size
Only for Emitter. A multiplier for children size.
Random
Random variation to the size of child particles.

Interpolated

Children are emitted between the Parent particles on the faces of a mesh. They interpolate between adjacent parents. This is especially useful for fur, because you can achieve an even distribution. Some of the children can become virtual parents, which are influencing other particles nearby.

Seed
Offset the random number table for child particles, to get a different result.
Virtual
Relative amount of virtual parents.
Long Hair
Calculate children that suit long hair well.

Common Options

Display
The number of children in the 3D View.
Render
The number of children to be rendered.

Effects

../../../_images/physics_particles_emitter_children_round-clump.png

From left to right: Round: 0.0, Round: 1.0, Clump: 1.0, Clump: -1.0, Shape: -0.99.

Length
Length of child paths.
Threshold
Amount of particles left untouched by child path length.
Size
The radius in which the children are distributed around their parents. This is 3D, so children may be emitted higher or lower than their parents.
Roundness
The roundness of the children around their parents. Either in a sphere (1.0) or in-plane (0.0).
Seed
Offset in the random number table for child particles, to get a different randomized result.

Clumping

Reference

Panel:Particle System ‣ Children ‣ Clumping
Use Clump Curve
Use 曲线部件 instead of parameters.
Clump
Clumping amount along child strands. The children may meet at their tip (1.0) or start together at their root (-1.0).
Shape
Form of Clump. Either inverse parabolic (0.99) or exponentially (-0.99).
Use Clump Noise

Creates random clumps around the parent hair.

Clump Noise Size
The size of the clumps.

Roughness

Reference

Panel:Particle System ‣ Children ‣ Roughness
Use Roughness Curve
Use 曲线部件 instead of parameters.
Uniform, Size
It is based on children location so it varies the paths in a similar way when the children are near.
Endpoint, Shape
"Rough End" randomizes path ends (a bit like random negative clumping). Shape may be varied from <1 (parabolic) to 10.0 (hyperbolic).
Random, Size, Threshold
It is based on a random vector so it is not the same for nearby children. The threshold can be specified to apply this to only a part of children. This is useful for creating a few stray children that will not do what others do.

Kink

Reference

Panel:Particle System ‣ Children ‣ Kink
../../../_images/physics_particles_emitter_children_kink.png

Child particles with Kink.

From left to right: Curl, Radial, Wave, Braid, Spiral.

With Kink you can rotate the children around the parent. See Fig. Child particles with Kink. above picture for the different types of Kink.

Kink Type
Nothing
Deactivated.
Curl
Children grow in a spiral around the parent hairs.
Radial
Children form around the parent a wave shape that passes through the parent hair.
Wave
Children form a wave, all in the same direction.
Braid
Children braid themselves around the parent hair.
Spiral

Generates a spiral at the end of each hair.

Radius, Resolution
Define the overall size.
Shape
Makes a the spiral grow in- or outward.

Note

Alignment Limitations

When hair is pointing straight up (along the chosen spiral axis, default Z), spirals may not show up! This is a limitation of the projection method used. Giving a slight tilt or random orientation to hairs fixes this.

Amplitude
The amplitude of the offset.
Clump
How much clump effects kink amplitude.
Flatness
How flat the hairs are.
Frequency
The frequency of the offset (1/total length). The higher the frequency the more rotations are done.
Shape
Where the rotation starts (offset of rotation).