Overview

The Cloth shader is a specialized shader for rendering cloth surfaces. It can simulate a wide range of cloth types, from canvas, silk, velvet, fabric, leather, and even rubber (ex: scuba diver suit).

Cloth Shader Params

Shader Gen Params

Cloth Properties

In general cloth isn't very reflective (i.e no specular highlights). Also depending on the cloth type (like velvet for example), it reflects more/less light depending on the view position.

One interesting property of some cloth types is that it's slightly brighter on sharper angles (i.e: on silhouettes), this is mainly due to fibers present on cloth reflecting and letting light pass by, which gives cloth a fuzzy/furry look (quite visible on wool/cotton made cloth).

Some cloth types are slightly reflective, like leather and silk. On these types of cloth, specular highlight has a special anisotropic (AnisotropicHighlights) property.

Using the Cloth Shader

The shader replicates all the above properties, and it's quite simple to use. There are 5 default parameters:

Diffuse Falloff

Diffuse falloff = 0	Diffuse falloff = 0.5 (default)	Diffuse falloff = 1

Fuzzyness Strength

Fuzzyness Strength = 0	Fuzzyness Strength = 1.5 (default)	Fuzzyness Strength = 10

Fuzzyness smoothness

Fuzzyness smoothness = 0	Fuzzyness smoothness = 1 (default)	Fuzzyness smoothness = 10

Fuzzyness spreading amount

Fuzzyness spreading amount = 0	Fuzzyness spreading amount = 1 (default)	Fuzzyness spreading amount = 10

Fuzzyness Saturation

The fuzzy layer, gets it's color from the diffuse layer, but in some cases, for example if the diffuse color is quite colorful we get some oversaturation on the fuzzy layer.

This parameters allows you to change the saturation of the diffuse texture used for the fuzzy. The lower the value the grayscale it gets, the higher the more saturated.

Fuzzyness Saturation = 0	Fuzzyness Saturation = 1 (default)	Fuzzyness Saturation = 2

Case Study: Silk

In this mini-tutorial, we'll check how to achieve a silk look. A nice way of doing this is by first getting photographs of the look you want to achieve and use them as a reference. For this one, I tried to find some generic looking silk cloth.

• Here's our original model. First step I did, was to try to match the colors, by making a diffuse texture similar in photoshop:

• Next step, was to match surface fuzzyness by setting fuzzy smoothness and spreading to 3.0, so that we got a nice fuzzy look (and similar to reference):

• Silk has some interesting specular highlights, so next step was to activate the Anisotropic Specular shader parameter.

• From the top image, we see that specular is completely out of place, too bright, colors don't match at all. Lets adjust it by setting a specular map with a similar color to the diffuse texture.

• The only thing left is changing the Anisotropic Shape to 0.8 so that we get a radial specular highlight shape. Also fuzzyness, is not as strong as in reference image, lets increase Fuzzyness Strength to 2.2