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UVW Map Modifier 905
UV W Ma p Modifier
Select an object. > Modify panel > Modifier List > UVW
Map
Select an object. > Modifiers menu > UVW Map
Mapping a sphere and a box.
By applying mapping coordinates to an object, the
UVW Map modifier controls how mapped and
procedural materials appear on the surface of an
object. Mapping coordinates specify how bitmaps
are projected onto an object. The UVW coordinate
system is similar to the XYZ coordinate system.
The U and V axes of a bitmap correspond to the X
and Y axes. The W axis, which corresponds to the
Z axis, is generally only used for procedural m aps.
A bitmap’s coordinate system can be switched in
the Material Editor to VW or WU, in which case
the bitmap is rotated and projected so that it is
perpendicular to the surface.
Primitive objects, like spheres and boxes, can
generate their own mapping coordinates, as
can loft objects and NURBS surfaces. Scanned,
imported, or hand-constructed polygonal or patch
models do not have mapping coordinates until a
UVW Map modifier is applied.
Note: Draw ings that are imported or linked from
Autodesk Architec tura l Desktop and Autodesk
Revit do retain t he mapping coordinates that were
assigned to objects by those products.
IfyouapplyaUVWMapmodifiertoanobject
w ith built-in mapping coordinates, the applied
coordinates take precedence if
map channel (page
3–1060)
1intheUVWMapmodifierisused.
The Generate Mapping Coordinates option,
available during the creation of primitives, uses
map channel 1 by default.
You use the UVW Map modifier to:
• Apply one of the seven types of mapping
coordinatestoanobjectonaspecifiedmap
channel. A diff use map on map channel 1 and a
bump map on map channel 2 can have different
mapping coordinates and can be cont rolled
separately by using two UVW Map modifiers
in the modifier stack
• Transform the mapping gizmo to adjust map
placement. Objects with built-in mapping
coordinates lack a gizmo .
• Apply mapping coordinates to an object with
no mapping coordinates, an imported mesh,
for example.
• Apply mapping at the sub-object level.
Map Channels
You can control the type of mapping coordinates
and the placement of t he mapping gizmo for each
bitmap in a material that uses multiple bitmaps by