Fur Description node

Below are descriptions of the attributes in the Fur Description node.

Related topics

Change fur attributes
Make fur clump together
Use Fur Presets
Copy fur descriptions into other scenes
FurDescription

Replace the default name for the fur description with something meaningful (for example, eyebrowFur).

Light Model

Select the light model you want applied to the fur description.

Ambient Only

Only the Base Ambient Color and Tip Ambient Color of the fur are used in the final color calculation.

Ambient + Diffuse

The Base Ambient Color and Tip Ambient Color values are added to the Base Color and Tip Color values respectively.

Ambient + Diffuse + Specular

The Base Ambient Color and Tip Ambient Color values are added to the Base Color and Tip Color values respectively, and the Specular values are added to the hairs according to the Specular Sharpness.

Specular Only

Only the specular lights (highlights) for the fur are rendered.
Density

Type the number of hairs you want distributed either across all surfaces the fur description is attached to or on each surface the fur description is attached to.

To distribute the hairs across all surfaces the fur description is attached to, in the Fur Render Options section, set the Calc. Area Values to Globally. The hairs for each fur description are distributed evenly over all surfaces with fur descriptions attached, regardless of which fur description is attached.

To distribute the hairs on each surface the fur description is attached to so that the distribution of hairs for one fur description does not affect the distribution for another fur description, in the Fur Render Options section, set the Calc. Area Values to Per Fur Description.

For details, see Set up Fur Render Settings before rendering. Per Fur Description is the default.

To use the given density value on each surface the fur description is attached to, you must set the Calc. Area Values fur global option to Off.

Global Scale

Use this setting to adjust the Base Width, Tip Width, Length, and Offset values by a common factor (including mapped values). This scales the hairs uniformly.

Assigned Surfaces

Lists the surfaces that have the current fur description assigned to them.

Bake Attribute

You can map textures to attributes, but the maps must be simple file textures. The Fur renderer only understands simple file textures. You can map any shading network including procedural textures to a fur attribute, but you must convert them into file textures by baking them.

If you map attribute values using the method available by going to the Details section of the Attribute Editor, you can only map file textures, and therefore do not need to bake them.

If you map values using any other method, (or example, drag and drop, or the Map button, you must bake the map.

In the Bake Attribute drop-down list, select the attribute for which you want to convert maps to file textures and click the Bake button. Fur saves the map in .IFF format in the furAttrMap directory. If you rebake an attribute the old map is overwritten.

For details about mapping attributes, see Map fur attribute values.

Map Width, Map Height

These are the width and height values for attribute maps you create using Bake Attribute and the Bake button. Also when you paint fur attributes on a surface using the Paint Fur Attributes Tool, Fur creates value grids the size of which are defined by the number of U and V Samples. When you render a scene, Fur exports these values to maps that the renderer can use. You can define the size of the exported map. (These values are not used if you import value maps in the fur description.)

These values set the width and height of the attribute map to be used by the renderer. The default is 256x256.

Base Color

Defines the color of the fur base. Use the slider to adjust the value. Click the Base Color box and select the fur base color from the Color Chooser.

Use the Map button to map a file texture to the base color. You must bake the map to convert it to a file texture. See Bake Attribute.

TipMake the base color of the fur the same as the surface’s material color.

Tip Color

Defines the color of the fur tip. Use the slider to adjust the value. Click the Tip Color box and select the fur tip color from the Color Chooser.

Use the Map button to map a file texture to the tip color. You must bake the map to convert it to a file texture. See Bake Attribute.

TipFor more realistic looking fur, start by making the Tip Color the same as the Base Color. Then reduce the color Saturation and increase the Value so the tip is slightly lighter than the base.

Base Ambient Color
Defines the ambient color of the fur base. This color is added to the Base Color to produce the effect of ambient lighting. Use the slider to adjust the value. Click the Base Ambient Color box and select the base ambient color from the Color Chooser.

This option only has an effect if the selected Light Model includes Ambient.

NoteTrue ambient lights do not affect the fur color. In Maya, an ambient light with the Ambient Shade attribute set to 0 is a true ambient light. If the Ambient Shade attribute of an ambient light is greater than 0, then the light does affect the fur color.

By default, the Base Ambient Color is black (value of 0), which means the Base Color is not affected. As you lighten the Base Ambient Color (increase the color value), the Base Color becomes lighter.

Use the Map button to map a file texture to the base ambient color. If the map you apply is not a file texture, you must bake the map to convert it to a file texture. See Bake Attribute.
Tip

Start by making the Base Ambient Color a darker shade of the Base Color.

If the color of the rendered fur appears too rich, try reducing the color Saturation to make the Base Ambient Color more gray.
Tip Ambient Color
Defines the ambient color of the fur tip. This color is added to the Tip Color to produce the effect of ambient lighting. Use the slider to adjust the value. Click the Tip Ambient Color box and select the tip ambient color from the Color Chooser.

This option only has an effect if the selected Light Model includes Ambient.

By default, the Tip Ambient Color is black (value of 0), which means the Tip Color is not affected. As you lighten the Tip Ambient Color (increase the color Value), the Tip Color becomes lighter.

Use the Map button to map a file texture to the tip ambient color. You must bake the map to convert it to a file texture. See Bake Attribute.
Tip

Start by making the Tip Ambient Color a darker shade of the Tip Color.

If the color of the rendered fur appears too rich, try reducing the color Saturation to make the Tip Ambient Color more gray.
Specular Color

Defines the color of shiny highlights on the fur. Use the slider to adjust the specularity value. Click the Specular Color box and select the specular color from the Color Chooser.

This option only has an effect if the selected Light Model includes Specular.

Use the Map button to map a file texture to the specular color. If the map you apply is not a file texture, you must bake the map to convert it to a file texture. See Bake Attribute.

TipStart by using the default Specular Color (gray).
If the rendered fur appears too shiny, reduce the value of the Specular Color and try increasing Specular Sharpness.

Specular Sharpness

Defines the sharpness of the fur highlight. A larger number yields a sharper (smaller) specular highlight.

This option only has an effect if the selected Light Model includes Specular.

TipStart by using the default Specular Sharpness value (50).
If the rendered fur appears too shiny, reduce the value of the Specular Color and try increasing Specular Sharpness.

Length
Defines the fur length in world units. Use the slider to adjust the length.
NoteIf you want to paint fur length when the fur description length is greater than 1, do the following:

Use the Artisan Paint Fur Attributes Tool to flood the selected surface with a Length value of 1.

Then set the Map Multiplier in the Length section to the desired number, for example, 3. For details, see Change attribute map value ranges. You can now paint values between 0 and the value set for the Multiplier.
Baldness

Defines how much fur is on the surface. Use the following settings as guidelines:

1.0

Full fur

0.0

Total baldness.

NoteYou can paint or map 256 levels of baldness, but fur feedback can display only 16 different levels.

TipUse Baldness when you have areas on a model that require a different fur description (for example, a beard, or eyebrows). Attach a new fur description to the surface with the Baldness set to 0 and either map higher Baldness values or use the Artisan Paint Fur Attributes Tool to paint higher Baldness values on the surface. For an example of this workflow, see Add whiskers.

Inclination

Sets the amount of inclination (slope). Use the following settings as guidelines:

0.0

No inclination. The fur is fully erect (normal to the surface). This is the default.

0.5

Partial inclination.

1.0

Fully inclined. The fur lies flat (tangent to the surface at the root).

Roll

Rotates the fur about the surface V axis. You can achieve almost any fur angle using Polar and Inclination, so use this option only when the fur has curl and you want the curls to lie flat. Use the following settings as guidelines:

0.0

-90 degree rotation.

0.5

No rotation. This is the default.

1.0

90 degree rotation.

In the following examples, the Inclination is set to 0.
Polar

Rotates the fur about the surface normal. Use the following settings as guidelines:

0.0

-180 degree rotation.

0.5

No rotation. This is the default.

1.0

180 degree rotation.

NoteIf the inclination is set to 0 and the base curl, tip curl, and roll are set to 0.5, the fur is actually on the surface normal, so changes you make to the polar setting will have no apparent effect (and therefore “combing” will have no apparent effect). For information on combing, see Comb fur.

In the following examples, the Inclination is set to 1.0.
Tip
- You can “comb” fur using the Paint Fur Attributes Tool. The direction you comb sets the polar values.
- To quickly change the direction the fur lies in, select Fur > Offset Fur Direction byand select the appropriate option. For more information, see Offset the direction fur grows.
Base Opacity

Defines the opacity of the fur base. Use the following settings as guidelines:

0.0

Completely transparent base.

1.0

Completely opaque base.

Tip Opacity

Defines the opacity of the fur tip. Use the following settings as guidelines:

0.0

Completely transparent tip.

1.0

Completely opaque tip.

TipFor more realistic looking fur, make the tip slightly transparent (try a value of 0.7).

Base Width

Defines the width of each hair at the base, in world units.

TipTo ensure full coverage of the underlying skin without increasing density (and render time), make the Base Width wider than the Tip Width.

Tip Width

Defines the width of each hair at the tip, in world units.

Base Curl

Defines the amount of curl at the base of the fur. The fur tip is not influenced by this value. Use the following settings as guidelines:

0.0

Half-circle curl to one side.

0.5

No curl.

1.0

Half-circle curl to the other side.

TipFor a curly effect, make the base curl and tip curl values greater than 1. In the following example, Length=15, Base Curl=10, Tip Curl=5, Scraggle=0.1, and Segments=100. Polar and Inclination are both set to 1.0.

Tip Curl

Defines the amount of curl at the tip of the fur. The fur base is not influenced by this value. Use the following settings as guidelines:

0.0

Half-circle curl to one side.

0.5

No curl.

1.0

Half-circle curl to the other side.

TipFor a curly effect, make the base curl and tip curl values greater than 1. See Base Curl.

Scraggle

Defines how crooked the fur is. Use the following settings as guidelines:

0.0

No scraggle.

1.0

Full scraggle. This is defined by the Scraggle Frequency.

NoteA small scraggle value produces a more realistic fur effect.

Scraggle Frequency

Defines the amount of change over each length of hair. The higher the value, the more changes there will be along each length of hair (the hair becomes more deformed).

NoteYou may need to increase the number of Segments to accurately reflect the detail produced by a high frequency. See Segments.

Scraggle Correlation

Defines how the scraggle of each hair relates to each other hair. Use the following settings as guidelines:

0.0

No correlation, so each hair has a unique scraggle.

1.0

Total correlation, so all hair “scraggles” in exactly the same way.

Clumping

The degree to which the hairs are pulled in towards the centre of the clump. The higher the clumping value, the more the hairs are pulled in. The range is from 0 to 1. The default is 0, which is no clumping.

Clumping Frequency

Controls how many clumps occur across the surface. The higher the frequency, the greater the number, and therefore the smaller the size of the clumps. The range is from 0 to 100. The default is 5.

As you increase the Clumping Frequency, the rendering time increases.

Unlike other Fur attributes, the number of feedback hairs (samples) affects the Clumping Frequency. For example, at a frequency of 100 there will be 1 clump for every feedback hair.

Clump Shape

Controls the shape of the curve of the hair as it is attracted to the center of the clump. Negative values create a concave shape and positive values create a convex shape. The range is from -10 to 10.

Segments

Defines the number of segments each fur is comprised of. For smoother curves, use more segments. The longer the fur, the more segments you need to produce a smooth result.

Attraction

Defines the amount of attraction this fur description has towards attractors. (Attractors are used to add movement to fur. For details, see Adding movement to fur.) Use the following settings as guidelines:

0.0

No attraction.

1.0

Full attraction.

You can use this attribute to balance how multiple fur descriptions are attracted towards the same set of attractors.

NotePainting a Fur Description's Attraction updates only one Fur Description, which is selected in the Paint Fur Attributes Tool Settings window. But painting Fur Curve Attractors’ Influence updates all the Fur Descriptions that are attached to the hair system. See Paint fur attribute values and Paint attractor set attribute values.

Offset

Defines how much to offset the fur description (in world units) from the surface it is attached to. When the Offset value is 0, the roots of the fur hairs start growing from the surface. When the value is less than zero, the roots start growing from inside the surface. When the value is greater than zero, the roots start growing from outside the surface. You can paint, map, and animate Offset.

Custom Equalizer

This option is available if you select Custom Equalizer Maps in the Fur Render Settings ( Fur > Fur Render Settings). You can map or paint this attribute like any other fur description attribute. For more information, see Equalizer Maps.

Details

For each Fur Description attribute there is a corresponding subsection in the Details section. Here you can define additional values for that attribute. For more information see Randomly vary fur attribute values and Change attribute map value ranges.

Map Offset: Set the factor you want to offset the attribute value by. For example, if you want to change the range of values for fur Length from the default 0-1 to 4-5, set the offset to 4.
Map Multiplier: Set the factor you want the value multiplied by. For example, if you want to change the range of values for fur Length from the default, 0-1, to 0-10, set the multiplier to 10.
Noise Amplitude: Set the noise value for the attribute. A value of 0 produces no noise or variation.
Noise Frequency: Set the noise frequency for the attribute. The larger the Noise Frequency, the more variation over distance or area.

mental ray

Volume Fur

Use the following attributes to render fur more efficiently and to improve fur render quality in mental ray. These attributes should be used in conjunction with the Volume fur shader. They cannot be used with the Hair Primitive fur shader. See mental ray for Maya Fur render settings for more information.

Samples: Controls fur anti-aliasing. This control is independent of the global settings.That is, you can obtain high quality fur even if the global anti-aliasing controls are set to a lower quality. Increase this value for better quality; however, higher values also increase render time. When there is motion blur, a small samples value is generally sufficient. The range is from 1 to 8. Default is 5.
Motion Blur: Enables motion blur. For more information, see Motion blur in the Rendering guide.
Motion Samples: Sets the anti-aliasing quality in the time domain. Increase this value to improve the quality of the render; however, higher values also increase render time. The faster the fur moves, the higher this value should be. The range is from 1 to 64. The default is 11.
Use Shadow Density Grid: Use this feature to accelerate fur self-shadows and shadows cast from one fur object onto another. When this feature is on, self-shadows are not raytraced; instead, they are approximated using a volumetric fur representation. When this feature is on, scenes often render faster.

Use in conjunction with Shadow Density Scale to control the self-shadow opacity.
Shadow Density Scale: Sets the opacity of self-shadows. You must manually set this attribute when you turn on Use Shadow Density Grid; it cannot be automatically calculated.