2009

Table Of Contents
In practical usage, the Diffuse setting makes a surface appear brighter.
The name diffuse comes from a property in physics that describes how
light spreads after it strikes a surface. A surface with a high diffuse property
spreads the light that strikes it, making the object appear brighter.
Like the Diffuse attribute, the other Common Material Attributes also
refer to general characteristics of light and the way a surface reacts to
light.
The next section in the Attribute Editor, Specular Shading, contains
attributes that control the appearance of shiny highlights on the surface.
Next, youll alter the surface specularitythe amount of light that reflects off
a surface, resulting in shiny highlights.
Modifying surface specularity
When light reflects in a concentrated manner off of a surface, a specular
highlight results. Specular highlights can be thought of as pseudo reflections
of bright areas in the scene (sunlight, bright lights, and so on). Modifying the
specular attributes affects the perceived reflectivity for a surface. When you
reduce the specularity, you in turn reduce the perceived reflectivity.
To modify the specularity of a material
1 In the Specular Shading section of the Attribute Editor, move the
Eccentricity slider back and forth to change the size of the shiny
highlights.
2 Move the Specular Roll Off slider to change the blend between highlighted
and other areas of the surface.
Changes to this attribute do not alter the surface in the scene view, so
you need to check the Material Sample in the Attribute Editor (see the
408 | Chapter 9 Rendering