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Unwrap UVW Modifier 869
modifier to do both. You can select sub-object
vertices,edges,orfaces/patches,storesub-object
selections as named selections, map them using
planar and other methods, and then edit the UVW
coordinates for each sub-object selection, all from
within the Unwrap UVW mo difier. For example,
to map a character’s face using three planar maps,
you could create three sub-object selections of
the front and sides of the f ace, planar-map t he
selections individually, and then edit the UVW
coordinates for each selection, all without leaving
the Unwrap U VW modifier.
What Happens to E xisting UV W
Coor dina tes
When you apply the Unwrap UVW modifier, it
stores the object’s current mapping coordinates
in the modifier. If the object has no mapping
coordinates, the modifier creates new ones by
applying planar mapping. If the incoming data on
the stack is a face-level or polygon-level sub-object
selection, then only the UVWs for the selected
faces are brought into the modifier, and the
modifier’s sub-object levels are unavailable.
When the modifier is evaluated, its UV Ws are
reassigned to the object flowing down the pipeline.
So if the UVWs upstream are changed, the changes
won’t make it past the Unwrap UVW modifier. If
the Unwrap modifier is operating on a selection of
faces, then upstream changes to unselected faces
will still be able to flow past the Unwrap modifier.
Native Support for HSDS, Polygon
Object, and Patch mapping
UnwrapUVWsupportspolygonfacesandBezier
quad and tri patch faces in addition to triangles
and quads.
Below is a sample of what the various face types
look like based on the incoming type. For HSDS
and Poly surfaces, the b asic interface remains the
same,exceptthatthemaximumnumberofsides
per polygon increases from 4 to over two billion.
HSDS supports only one level of detail: the level at
which the mapping was. Patches have handles on
nonlinear ver tices. These handles work just like
regular patch handles.
Pinning Textures
Although not its primary purpose, you can use the
Unwrap UVW modifier to freeze UVWs. You can
apply mapping after an animated deformation and
have the mapping stick to the object. For example,
you can apply Unwrap UVW above a Morpher
modifier in the modifier stack, apply planar maps
and edit the UVW coordinates. The mapping will
follow the morphing geometry.
Procedures
To use Unwra p UVW with the non-Pelt mapping
meth ods :
This is a general overview of using the basic
Unwrap UVW tools available on the Modify panel
and the
Edit UVWs dialog (page 1–878) .Unwrap
UVW provides many additional tools, particularly
in the editor.
1. Apply the modifier and a texture-mapped
material to an object. Set the material to display
in the view p orts, set at least one viewport to b e
shaded (e.g., Smooth + Highlights), and turn
off Shade Selected Faces for that viewport, if
necessary, so the texture mapping is visible.
2. GototheFacesub-objectleveloftheUnwrap
modifier and make a selection of contiguous