Previous Next

                                                      886
           CHAPTER 10                                                          Document Interchange



           The first form is used to identify a generic artifact; the second is used for those
           that have an associated property list. Table 10.17 shows the properties that can be
           included in such a property list.

           Note: To aid in text reflow, it is recommended that artifacts be defined with proper-
           ty lists whenever possible. Artifacts lacking a specified bounding box are likely to be
           discarded during reflow.

                               TABLE 10.17 Property list entries for artifacts
KEY            TYPE            VALUE

Type           name            (Optional) The type of artifact that this property list describes; if present, must
                               be one of the names Pagination, Layout, Page, or (PDF 1.7) Background.

BBox           rectangle       (Optional; required for background artifacts) An array of four numbers in default
                               user space units giving the coordinates of the left, bottom, right, and top edges,
                               respectively, of the artifact’s bounding box (the rectangle that completely enclos-
                               es its visible extent).

Attached       array           (Optional; pagination and full-page background artifacts only) An array of name
                               objects containing one to four of the names Top, Bottom, Left, and Right, specify-
                               ing the edges of the page, if any, to which the artifact is logically attached. Page
                               edges are defined by the page’s crop box (see Section 10.10.1, “Page Bound-
                               aries”). The ordering of names within the array is immaterial. Including both
                               Left and Right or both Top and Bottom indicates a full-width or full-height arti-
                               fact, respectively.
                               Use of this entry for background artifacts is limited to full-page artifacts. Back-
                               ground artifacts that are not full-page take their dimensions from their parent
                               structural element. An example of such a background artifact is a colored back-
                               ground for a sidebar.

Subtype        name            (Optional; PDF 1.7) The subtype of the artifact. This entry applies only when the
                               Type entry has a value of Pagination. Valid values are Header, Footer, and
                               Watermark. Additional values can be defined for this entry, provided they com-
                               ply with the naming conventions described in Appendix E.


           The following types of artifacts can be specified by the Type entry:

           • Pagination artifacts. Ancillary page features such as running heads and folios
             (page numbers).
           • Layout artifacts. Purely cosmetic typographical or design elements such as
             footnote rules or background screens.

Previous Next