User Manual

Table Of Contents
Diffuse Color
A material’s Diffuse Color describes the base color presented by the material when it is lit
indirectly or by ambient light. If a diffuse texture map is provided, then the color value provided
here is multiplied by the color values in the texture.
Alpha
This slider sets the material’s Alpha channel value. This affects diffuse and specular colors
equally and affects the Alpha value of the material in the rendered output. If a diffuse texture
map is provided, then the Alpha value set here is multiplied by the Alpha values in the
texture map.
Opacity
Reducing the material’s Opacity decreases the color and Alpha values of the specular and
diffuse colors equally, making the material transparent.
Specular
The parameters in the Specular section describe the look of the specular highlight of the
surface. These values are evaluated in a different way for each illumination model.
Specular Color
Specular Color determines the color of light that reflects from a shiny surface. The more
specular a material is, the glossier it appears. Surfaces like plastics and glass tend to have white
specular highlights, whereas metallic surfaces like gold have specular highlights that inherit
their color from the material color. If a specular texture map is provided, then the value provided
here is multiplied by the color values from the texture.
Specular Intensity
Specular Intensity controls how strong the specular highlight is. If the specular intensity texture
is provided, then this value is multiplied by the Alpha value of the texture.
Specular Exponent
Specular Exponent controls the falloff of the specular highlight. The greater the value, the
sharper the falloff, and the smoother and glossier the material appears. If the specular exponent
texture is provided, then this value is multiplied by the Alpha value of the texture map.
Transmittance
Transmittance controls the way light passes through a material. For example, a solid blue
sphere casts a black shadow, but one made of translucent blue plastic would cast a much lower
density blue shadow.
There is a separate Opacity option. Opacity determines how transparent the actual surface is
when it is rendered. Fusion allows adjusting both opacity and transmittance separately. At first,
this might be a bit counterintuitive to those who are unfamiliar with 3D software. It is possible to
have a surface that is fully opaque but transmits 100% of the light arriving upon it, effectively
making it a luminous/emissive surface.
Attenuation
Attenuation determines how much color is passed through the object. For an object to have
transmissive shadows, set the attenuation to (1, 1, 1), which means 100% of green, blue, and red
light passes through the object. Setting this color to RGB (1, 0, 0) means that the material
transmits 100% of the red arriving at the surface but none of the green or blue light. This can be
used to create “stained glass”-styled shadows.
Chapter –82 3D Material Nodes 1782