Houdini 16.5

Hair and Fur

How to create, style, and add dynamics to hair and fur.

The tools the Hair Utils shelf let you quickly set up hair and fur objects, jump between objects, as well as animate and simulate. The tools on the Guide Process and Guide Brush shelf tabs are used to style the fur.

The main difference is that tools on the Guide Process shelf let you influence the placement and orientation of guide hairs by painting skin attributes, whereas the tools on the Guide Brush shelf use actual stroking tools to create hair and style it artistically.

To create fur, start with a piece of geometry and use the Add Fur tool on the Hair Utils shelf. By default, two nodes are created: Guide Groom and Hair Generate.

The Guide Groom and Hair Generate networks have the exact same set up with the exact same workflow, except the hair generation network has less outputs. This makes it very simple to use, since everything is done in SOPs with curves. The Guide Process node lets you layer many different operations, and very easily control where the operation takes place along the curve using ramps or by painting attributes on the skin. This allows you to easily create natural looking hair and fur very quickly.

One improvement is that there is no longer a separation between manipulating guide curve geometry or painting skin attributes. Everything flows through a single graph. All of the components that make up the groom are displayed in a single network. Each of the nodes also have at least 3 inputs and 3 outputs, which allows the 3 types of data to flow through the nodes. This results in a very clean and easy to read network, and eliminates the need to reference other nodes. Another advantage is that the operators can be placed in any order, which gives you complete control and flexibility.


Mantra uses the SOP network you create to do the grooming and does the cooking of the node network (SOP network) at render time. It does this without taking a license, which allows for rendering with Engine for hair, fur, and anything else that’s comprised of curves and points (grass).


Grooming should always be done on the static mesh, not the animated mesh.


Working with fur

Tools for creating fur

  • Add Fur

    Adds fur to a surface.

  • Create Guides

    Creates a guide curves from a skin geometry or manipulates the guides of another groom object.

  • Draw Hair

    Lets you add freehand-drawn hair guides to a fur object.

Tools for styling with guide processes

  • Initialize Guides

    Gives the guides an initial direction.

  • Curve Advect

    Advects curves using a vector field generated from curves drawn on the skin surface.

  • Reguide

    Interpolates guides between planted guides.

  • Set Direction

    Points guides in the direction of a vector.

  • Set Length

    Lengthens or shortens guide hairs.

  • Lift

    Lifts curves off the skin or flattens them against it.

  • Straighten

    Straightens the hair by bending each segment back so that it’s in the same direction as the previous segment.

  • Smooth

    Blends the shapes of the neighboring guides to create a smoother look.

  • Frizz

    Offsets the curve points along the guide hairs to create a frizzy look.

  • Bend

    Bends curves in a certain direction and by a certain angle.

  • Clump

    Creates bunches of guide hairs.

  • Part

    Lets you draw a parting line on the skin geometry.

  • Add White Hairs

    Adds the required attribute to mark hairs as white hairs in the standard hair shader.

Tools for styling with brushes

  • Screen Brush

    Lets you interactively groom hair in screen space.

  • Surface Brush

    Lets you interactively groom hair along the surface of your geometry.

  • Lift Hair

    Lets you interactively push hair away from the surface.

  • Clump Hair

    Lets you interactively pull hair into a clump.

  • Part Hair

    Lets you interactively push hair away from your stroke.

  • Length Adjust

    Lets you interactively vary the length of the ends of the hair.

  • Smooth Hair

    Lets you interactively smooth areas of hair.

  • Cut Hair

    Lets you interactively trim hair.

  • Extend Hair

    Lets you interactively lengthen hair.

  • Recache Strokes

    Recaches recorded strokes in all Guide Groom SOPs within a groom object.

Tools for animating and simulating fur

How to

Houdini 16.5

Getting started

Using Houdini

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  • Hair and Fur

    How to create, style, and add dynamics to hair and fur.

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