TYPE: SOP
TITLE: AttribCopy SOP

AttribCopy is used to copy attributes between groups of vertices, points, 
primitives, or between details.

Attributes are copied from a source group to a destination group.
The source and destination group must be of the same type,
but there is no restriction on the attribute class.  When copying a
detail attribute, the group field is ignored.

When copying, a general rule is applied when the size of the destination
is greater than the size of the source.  In this case, the elements
of the source are repeated in a cyclic fashion.  An analogous example
follows:

    Given a source pattern "ABC" and a destination pattern of length 8,
    the resulting destination pattern is "ABCABCAB".

The same logic applies to vertices, points, and primitives.  The order
in which the source and destination groups are specified will affect
the result of the copy.

If the copied attribute does not exist on the destination geometry,
it is created automatically.

e.g.)
    Use the AttribCopy operation to copy UV texture coordinates from
    one face to another.  The group type should be primitives,
    and the attribute class should be points or vertices (depending
    on where the UV attribute has been applied).

Parameters:
    Source Group             - A subset of the source geometry from which to
                               read attribute values.
    Destination Group        - A subset of the destination geometry whose
                               attribute values will be overwritten by the
                               values contained in the source geometry.
    Group Type               - The type of elements referenced in the Source
                               and Destination Group fields. The Source and
 		               Destination Group Types must be identical.
    
    Attribute                - Attribute to copy.  "Color" and "Texture UV"
                               are provided for convenience.  Other attributes
                               can be specified by name by selecting "Other
                               Attribute".
    Attribute Name           - When "Other Attribute" is selected, this is the
                               name of the attribute to copy.
    Attribute Class          - Where the attribute is located on the geometry.
                               Vertex, point, primitive, and detail attributes 
                               can be copied.  "Use Group Type" looks for the
                               attribute in the same place as specified by the
                               Group Type parameter.  "Auto Detect" first looks
                               in the place specified by the Group Type,
                               then looks for the attribute in vertices, points,
                               primitives, and detail (in that order).

See also: Attribute, AttribCreate, AttribMirror, AttribTransfer, GroupCopy,
	  Point, Primitive, Vertex
