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132 Chapter 17: Rendering
selections in other image-processing or
special-effects applications, such as Autodesk
Combustion. For example, you could select
all of the objects w ith a g iven material ID in
Combustion. The material ID corresponds
to the value you set for the material with the
material ID channel. Any g iven material ID wi l l
always be represented by the same color. The
correlation between a specific material ID and a
specific color is the same in Combustion. See
Mater ial ID Channel (page 2–1443).
• Matte: Renders a matte mask, based on selected
objects, material ID channel (effects IDs), or
G-Buffer IDs.
The Matte element displays an additional Matte
Texture Element rollout (page 3–141).
• Obje ct I D : Retains the object ID information
assigned to the object.
Roughly comparable to the material ID , the
object ID information is useful for selecting
objects based on an arbitrary index value in
another image-processing or special-effects
application. If you know that you will want to
select several objects at once, at a later time,
you c an assign them all the same object ID
in 3ds Max. By rendering with the object ID,
this information will be available in other
applications.
YouassigntheobjectIDwiththeObject
Properties d ialog > General panel > Object
Channel parameter.AgivenobjectIDisalways
represented by the same (arbitrary) color. The
correlation between a specific material ID and a
specific color is the same in Combustion.
When an Object ID entry is highlighted in the
element rendering list (page 3–136),theObject
ID Element rollout appears on the Render
Elements panel. Th is rollout lets you choo se
whether to base the render color of a given
object ID on the object color or the Object ID .
If you choose Object Color, the render color is
the object’s base color, as shown on the Create
panel > Name And Color rollout and at the top
of the other command panels, and is not based
on the Object ID. If you choose Object ID, an
arbitrar y color is assigned to each object based
on its Object ID .
• Pa int : The Paint component (surfaces) of Ink
’n Paint materials.
• Reflection: Thereflectionsintherendering.
• Refraction: The refractions in the rendering.
• Self-I llumination: The self-illumination
component of the rendering.
• Shadow: Theshadowsintherendering.This
element saves black-and-white shadows only.
See Compositing Rendered Elements (page
3–134).
Note: The mental ray renderer does not include
shadows created by global illu mination (page
3–106) and final gathering (page 3–111) in the
Shadow render element output.
• Specula r: The specular component of the
rendering.
• Ve l o c i t y : The motion information which can
be used in other applications for things such as
creating motion blur or retiming an animation.
The Velocit y element displays an additional
Velocity Element Parameters rollout (page
3–142).
• ZDepth:A grayscale representation of the
Z depth, or depth within the view, of objects
within the scene. The nearest objects appear
in white, and the depth of the scene in black.
Intermediate objects are in gray, the darker the
deeper the object is, within the view.
The Z Depth element displays an additional Z
Element Parameters rollout (page 3–143).
When you render one or more elements, a normal
complete rendering is also generated. In fact, the
element renderings are generated during the same