SECTION 9.5
797
3D Artwork
9.5.2 3D Streams
Beginning with PDF 1.6, the specification of 3D artwork is contained in a
3D
stream.
3D stream dictionaries, whose entries are shown in Table 9.35, can pro-
vide a set of predefined views of the artwork, as well as a default view. They can
also provide scripts and resources for providing customized behaviors or presen-
tations.
TABLE 9.35 Entries in a 3D stream dictionary
KEY
TYPE
VALUE
Type
name
name
array
(various)
(Optional)
The type of PDF object that this dictionary describes; if present,
must be
3D
for a 3D stream.
(Required)
A name specifying the format of the 3D data contained in the
stream. Currently, the only valid value is
U3D
.
(Optional)
An array of
3D view dictionaries,
each of which specifies a named
preset view of this 3D artwork (see Section 9.5.3, “3D Views”).
(Optional)
An object that specifies the default (initial) view of the 3D art-
work. It can be a 3D view dictionary (see Section 9.5.3, “3D Views”) or one of
the following types:
Subtype
VA
DV
•
An integer specifying an index into the
VA
array.
•
A text string matching the
IN
entry in one of the views in the
VA
array.
•
A name that indicates the first (
F
) or last (
L
) entries in the
VA
array.
Default value: 0 (the first entry in the
VA
array) if
VA
is present; if
VA
is not
present, the default view is specified within the 3D stream itself.
Resources
name tree
(Optional)
A name tree that maps name strings to objects that can be used by
applications or scripts to modify the default view of the 3D artwork.
The names in this name tree must be text strings so that they can be accessible
from JavaScript.
OnInstantiate
stream
(Optional)
A JavaScript script that is executed when the 3D stream is instanti-
ated.