Fur

V-Ray Fur is a very simple procedural fur plugin. The fur is generated only during render time and is not actually present in the scene, thus making the viewport faster. V-Ray Fur is more commonly used for simulating grass cover or textile fibers.

||V-Ray Asset Editor|| > Geometry (right-click) > Fur

||V-Ray Asset Editor|| > Create Asset (left-click) > Geometries > Fur

||V-Ray Objects Toolbar|| > Fur (left-click) > Add Fur to Selection

||V-Ray Objects Toolbar|| > Fur (right-click) > Remove Fur from Selection

Rhino Menus Ribbon

||V-Ray|| > Objects > Add Fur to Selection

Fur creation is possible in the V-Ray menus (V-Ray > V-Ray Objects > Apply Fur to Selection) and toolbars, as well as in the V-Ray Asset Editor (Asset Editor > Geometry > Fur and use the Apply to Selection context option). vrayFur command also applies Fur properties onto a selection.

Fur creation is available in the Rhino Properties V-Ray section as well.

When V-Ray Fur is applied to an object, a viewport widget resembling a strand appears on each face. The strand indicates the normal vector used by the Fur as well as the Fur length parameter value.

VRay Fur – Enables or disables the VRay Fur.

Distribution – Specifies how the density of strands is determined over the source object:

Per Face – Every face generates the specified number of fur strands. Specifies the number of fur strands per face of the source object.
Per Area – The number of strands for a given face is based on the size of that face. Smaller faces have fewer strands, larger faces have more strands. Every face has at least one strand.

Count (Face) – Specifies the number of fur strands per face of the source object when Per Face option is selected.

Count (Area) – The number of strands for a given face is based on the size of that face when Per Area option is selected. For more information, see the example Count Area below.

Density Map – The map is a multiplier for the strand density. Black portions of the map correspond to zero density (effectively no fur is generated in these areas). White represents the normal strand density, as specified by the Distribution parameter. See the Maps example below for more information.

Length – Specifies the length of the fur strands. See the Length example and the Maps example below for more information.

Thickness – Specifies the thickness of the fur strands. It measures the strand radius. See the Thickness example and the Maps example below for more information.

Taper – Adds a taper to the individual strands of fur. Increasing this value makes each strand thinner at its upper end and wider at its base. See the Taper example below for more information.

Gravity – Controls the force that pulls fur strands down along the Z-direction. See the Gravity example and the Maps example below for more information.

Bend – Controls the elasticity of the fur strands. When set to 0.0, the all strands are stiff and straight lines. Greater values cause the strands to bend (e.g. under the influence of the Gravity parameter). See the Bend example and the Maps example below for more information.

Global Scale – Globally controls the scale of the fur in the scene. See the Global Scale example below for more information.

Knots – Controls the number of connected straight segments the fur strands are rendered in.  See the Knots example below for more information.

Example: Count Area

Example: Length 

Example: Thickness

Example: Taper

Example: Gravity

Example: Bend

Example: Global Scale

Example: Knots

The Direction, Length, Thickness and Gravity parameters in this rollout add variation to their corresponding parameters from the Parameters rollout. Values range from 0.0 (no variation) to 1.0. See the Variance examples below for more information.

Bend Direction Map – Specifies a bend direction of the fur strands. This is the direction the fur strands are curved to (the amount of curvature is also controlled by the Bend parameter). The red component of the texture is offset along the U texture direction, the green component is the offset along the V texture direction, and the blue component is the offset along the surface normal.

Initial Direction Map – Specifies the initial direction of the fur strands. The red component is offset along the U texture direction, the green component is the offset along the V texture direction, and the blue component is the offset along the surface normal.

Variance Direction

Variance Gravity

Variance Length

Variance Thickness

Curl – When enabled, adds curls to the fur.

Curl Radius – Specifies the radius of an individual curl. See the Curl Radius example below for more information.

Curl Radius Variation – Allows you to add variation to the curl radius of the fur strands. See the Curl Radius Variation example below for more information.

Number of curls – Specifies the number of curls on a strand. See the Number of Curls example below for more information.

Curl Map – This map is a multiplier for the strand Curl. Black portions of the map correspond to no curl, and white represents the set curl, as specified by the Distribution parameters. See the Maps example below.

Example: Curl Radius

Example: Curl Radius Variation

Example: Number of Curls

Example: Maps 

Level of detail – When enabled, V-Ray generates less fur geometry for parts of the scene that are far away from the camera. This is done by decreasing the density of the fur strands and increasing their thickness. The level of detail function helps for two things. One, it conserves memory by decreasing the detail where it is too far to be visible, and two, it helps to reduce animation flickering of very fine fur strands when they are far from the camera.

Start Distance – Specifies the distance from the camera at which V-Ray starts implementing the Level of detail adjustment. Up to this distance the fur is generated as specified by the user. After that V-Ray decreases the density and increase the thickness of the strand by a factor of two for every n units of space specified by the Rate parameter. See the Start Distance example below.

Rate – The rate at which the the Level of detail adjustment is applied. Starting from the distance specified in the Start distance parameter, V-Ray decreases the density and increase the thickness of the strands by a factor of two for every n units of space specified by the Rate parameter. See the Rate example below.

Example: Start Distance

Example: Rate

Material toggle– When disabled, the V-Ray Fur uses the front-face material of the base mesh for shading. When enabled, it allows you to assign a different material.

Material selector– Specifies a scene material that is applied to the fur geometry. If a texture is used in this material, the texture placement is based on the base mesh UVs/ placement.

The input slot () of the Material has a context menu available, if a material is slotted. Note that materials can also be drag-and-dropped into the slot. When you right-click on it, you can Copy, Cut or Clear the selected material. If you left-click on it, the Asset Editor jumps to the slotted material.

Gravity Direction – Manually specifies the gravity vector.

In Rhino's Properties panel reside several V-Ray rollout controls, one of which is for V-Ray Fur.

The button applies new Fur properties to a selection. A selection can receive already existing Fur properties from another object. The button opens the geometry property panel of the selected Fur asset in the V-Ray Asset Editor for edition.

Make Unique – Makes unique the selected instance of a fur. It creates a new Fur item in the Asset Editor that is linked only to the selected object.

Select Instances – Selects all objects that have an instance of the same fur in the viewport.

Show in VP – Enable to provide visual representation of the fur geometry in in the viewport.