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DGS Material (mental ray) 1389
DGS M ater ia l (mental ra y)
Material Editor > Type button > Material/Map Browser >
DGS Material (physics_phen )
Note: The DGS m aterial does not appear in the Browser
unless you have enabled the mental ray extensions by
using the m ental ray Preferences panel. In addition, you
can’t assign shaders to the options in this rollout unless
the mental ray renderer is the currently active renderer.
DGS stands for Diffuse, Glossy, Specular. This
material is a mental ray phenomenon (a scripted
shader tree) that provides a physically accurate
simulation of a surface. Using DG S materials with
the mental ray renderer is comparable to using the
Architectural material with the default scanline
renderer. The DGS material’s basic components
appear on the P arameters rollout. You can assign
shaders to these components, creating a material of
greater complexity. Buttons for assigning shaders
are on both the Parameters rollout and the Shaders
rollout.
Inter face
Parameters rollout
Note: The button to the right of each control
is a shortcut shader button. Clicking one of
these buttons displays the
Material/Map Browser
(page 2–1256)
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 1–157)
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 any of its surroundings.
Shiny—Sets the w idth of glossy highlights. The
larger this va lue, the smaller the highlights.
Default=30.0.
Transparency—Specifies the transparency. The
effect ive r ange of Transparenc y is from 0.0 to 1.0.
At 0.0 the material is fully opaque. At 1.0 it is fully
transparent. D efault=0.0.
Wa rn in g: You can set the value of Transparency to be
greater than 1.0, but this has no effect. An anomaly o f
the user interface for shaders in the mental ray and lume
libraries, is that spinner values are not “clamped” to lie
within their effective ranges, as they are for controls in
3ds Max.
The value of Transparency also indirectly specifies
the reflectivity of the material, which is calculated
as 1.0 minus the Tr ansparency va lue.
Index Of Refra ction—Specifies the IOR. In the
physical world, the IOR results from the relative
speeds of l ig ht through the tr ansparent material
and the medium the eye or the camera is in.
Typically this is related to the object’s density. The
higher the IOR, the denser the object. Default=1.5.
See
Extended Parameters Rollout (Standard
Material) (page 2–1312)
for a list of IOR values for
commonly encountered materials.