Page 505 - Kitab3DsMax

Chapter 16: Creating and Applying Standard Materials

Tip
The Blinn shader is typically used to simulate softer materials like rubber, but the Phong shader is better for hard
materials like plastic. n

Anisotropic shader
The Anisotropic shader is characterized by noncircular highlights. The Anisotropy value is the difference
between the two axes that make up the highlight. A value of 0 is circular, but higher values increase the dif-
ference between the axes, and the highlights are more elliptical.
Most of the parameters for this shader are the same as those for the Blinn shader, but several parameters of
the Anisotropic type are unique. The Diffuse Level value determines how bright the Diffuse color appears.
This is similar to Self-Illumination, but it doesn’t affect the specular highlights or the shadows. Values can
range from 0 to 400.
Compared with the Blinn shader, the Specular Highlight graph looks very different. That is because it dis-
plays two highlight components that intersect at the middle. The Specular Level value still controls the
height of the curve, and the Glossiness still controls the width, but the Anisotropy value changes the width
of one axis relative to the other, creating elliptical highlights. The Orientation value rotates the highlight.
Figure 16.6 compares the Specular Highlight graphs for the Blinn and Anisotropic shaders.

Tip
Because the Anisotropy shader can produce elliptical highlights, it is often used on surfaces with strong grooves
and strands, like fabrics and stainless steel objects. n

FIGURE 16.6
The Specular Highlight graph for the Blinn and Anisotropic shaders

Figure 16.7 shows several materials with the Anisotropic shader applied. The first three images have
Anisotropic values of 30, 60, and 90, and the last two images have Orientation values of 30 and 60.
Multi-Layer shader
The Multi-Layer shader includes two Anisotropic highlights. Each of these highlights can have a different
color. All parameters for this shader are the same as the Anisotropic shader described previously, except
that there are two Specular Layers and one additional parameter: Roughness. The Roughness parameter
defines how well the Diffuse color blends into the Ambient color. When Roughness is set to a value of 0, an
object appears the same as with the Blinn shader, but with higher values, up to 100, the material grows
darker.
Figure 16.8 shows several materials with a Multi-Layer shader applied. The first two images have two spec-
ular highlights, each with an Orientation value of 60 and Anisotropy values of 60 and 90. The third image
has an increased Specular Level of 110 and a decrease in the Glossiness to 10. The fourth image has a
change in the Orientation value for one of the highlights to 20, and the final image has a drop in the
Anisotropy value to 10.

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