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1580 Chapter 16: Material Editor, Materials, and Maps
Irra diance weight (indirect illumination)—
The
influence of indirect light (photons and final
gathering) on the sur face. It is internally divided
by pi (3.14159); for example, a value of 1.0 means
the standard 1 .0/pi weight.
Global weight—A global tuning parameter that
affects the entire diff use, flake, and specular
subsystems.Itdoesnotaffectreflectionsordirt.
Shaders rollout
This rollout enables application of maps or shaders
to any of the Car Paint parameters. Of course, you
canapplyashadertoaparameterbyclickingits
Mapbutton,sotheprincipalvalueofthisrollout
is that it also lets you toggle a par ameter’s shader,
using the check box, without removing the map.
DGS Ma ter ial (menta l ra y)
Material Editor > Type b utton > M aterial/Map Browser >
DGS Mater ial (physics_phen)
Note: The DGS m aterial appears in the Browser only if the
mental ray renderer is the currently active renderer.
DGS st ands for Diff use, Glossy, Specular. This
material is a mental ray phenomenon (a scripted
shader tree) that provides a physically accurate
simulation of a surface. Using DGS materials with
the mental ray renderer is comparable to using
the Architectural material (page 2–1535) with the
default scanline renderer.
The DGS material’s basic components appear on
the Parameters rollout. You can assign shaders to
these components, creating a m aterial of greater
complexity. Buttons for assigning shaders are
on both the Parameters rollout and the Shaders
rollout.
Interfa ce
Parameters rollout
Note: The button to the rig ht of each control
is a shortcut shader button. C l icking one of
these buttons displays the Material/Map Browser
(page 2–1412) so you can assign a shader to this
component. When a map or a shader has been
assigned to a component, this button displays
theletter“M,”andthecomparablebuttononthe
Shaders rollout displays the map or shader name.
Diffuse—Click the color swatch to display a Color
Selector (page 1–161) and change the material’s
diffuse color.
Glossy Highlights—Click the color swatch to
displayaColorSelectorandchangethecolorof
glossy highlights.
Specular—Click the color swatch to display a Color
Selector and change the color of mirror reflections.
When the specular color is white, the material
is 100 percent reflective, like a mirror. When
the specular color is black, the material does not
reflect an y of its surroundings.
Shiny—Sets the width of glossy hig hlights. The
larger this value, the smaller the highlights.
Default=30.0.
Transparency—Specifies the transparency. The
effect ive r ange of Transparency is from 0.0 to 1.0.
At 0.0 the material is fully opaque. At 1.0 it is fully
transparent. Default=0.0.