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1618 Chapter 16: Material Editor, Materials, and Maps
bitmaps; other kinds of 2D maps are generated
procedurally.
• 3D maps (page 2–1662) are patterns generated
procedurally in t hree d imensions. For example,
Marble has a grain that goes through the
assigned geometry. If you cut away part of an
object with Marble assigned as its texture, the
interior matches the exterior.
• Compositors (page 2–1687) are for compositing
other colors or maps.
• Color Modifiers (page 2–1692) alter the color
of pixels in a material.
• The "O ther" category includes maps that create
reflections and refractions (page 2–1695).Italso
includes mental ray shaders (page 2–1710) ,
Normal Bump maps, (page 2–1731) and Camera
Per-Pixel Projection m aps (page 2–1732).
Maps and mental ray Shaders
When the mental ray renderer (page 3–78) is
active, the Material/Map Browser also lists mental
ray shaders. Shaders are similar to maps, but use
yellow icons. You assign them the way you do
maps. The mental ray shaders don’t fit into the
map categories described in the previous sect ion,
and aren’t described in this topic. See mental
ray Shaders (page 2–1710) for links to shader
descriptions.
mental ray maps in the browser’s list are shown with yellow
icons.
Tip: When the default scanline renderer is active,
you can v iew mental ray shaders in the Browser
list, and assign them, by turning on Incompatible
in the Show group. Incompatible shaders in the
list are displayed in gray.
Maps and Mapping Coordinates
Maps have a spat ial orientation. When you
apply a material w ith maps in it to an object, the
object must have mapping coordinates. These are
specified in ter ms of UVW axes local to the object.
Most objects have a Generate Mapping
Coordinates toggle. You can turn this on to
provide default m apping coordinates. If the object
has this toggle, it is also turned on automatical ly
when you render the scene, or use Show Map In
View port (page 2–1445).
Some objects, such as editable meshes, don’t have
automatic mapping coordinates. For these types
of objects, you can assign coordinates by applying
a UVW Map modifier (page 1–922). If you assign a
map that uses a mapping channel, but don’t apply
a UVW Map modifier to the object, the renderer
displays a warning that lists objects that require