Page 200 - Graphic Design and Print Production Fundamentals

188 Chapter 6. Imaging
Layout

When working with variable data documents, there are special layout considerations you should be
aware of. Because word lengths will change per record, there needs to be sufficient space to
accommodate the largest and smallest record, and prevent oversetting while maintaining the desired
visual appearance. This challenge is compounded by the prolific use of proportional fonts. Character
widths differ with each letter so word lengths will vary even when the number of characters is the
same. This can also force a paragraph to reflow onto another page and change the number of pages
in the document. Additional scripting may be required to handle reflow scenarios. Some applications
use special copy-fitting algorithms to dynamically fit text into a defined area. The use of tables for
layout purposes can also be helpful. Because we are dealing with dynamically generated documents,
we may also want to vary the images. Using images with a consistent size and shape make it easier to
work with. Transactional documents, such as statements and invoices, extensively use numbers. Most
fonts, including proportional ones, keep numbers mono-spaced. In other words, every number character
occupies the same amount of space. This is important because, visually, we want numbers to be right
justified and lining up vertically in columns with the decimal points aligned. There are, however, some
fonts that do not follow this common practice. These fonts may be suitable for use in a paragraph but are
not for displaying financial data.

Software

Software that can generate a data-driven document is required for variable data printing. In the early
days of VDP, there weren’t many choices for designers. It was common practice to hand code VDP
in PostScript, since it was both a programming language and a PDL. Applications like PageMaker
and Illustrator were PostScript design applications but lacked VDP capabilities. Applications like
PlanetPress emerged as dedicated PostScript VDP applications. Today, designers have a wide variety of
software available for creating VDP. There are three basic VDP software types: a built-in function within
a page layout or word-processing software, a third-party plug-in, or a dedicated VDP application.

Microsoft Word, for example, has a mail merge function but does not have the ability to vary images,
just text. Adobe InDesign has the data merge function, which is basically a mail merge but includes the
ability to vary images as well. In both these examples, business rules would be applied to the data prior
to using it in these applications.

There are a number of plug-ins available for InDesign that are very sophisticated. These leverage the
extensive page layout capability of InDesign while adding scripting and other VDP specific capabilities.
XMPie and DesignMerge are examples of these types of plug-ins. FusionPro is another plug-in based
VDP product, and while it does have an InDesign plug-in, it only uses this to allocate variable text and
image boxes in the layout. Business rules and specific content are applied in its complement plug-in for
Adobe Acrobat.

PlanetPress and PrintShop Mail are examples of dedicated applications that combine both page layout
and VDP functions. Although they are very strong in VDP functionality, they sometimes lack the
sophistication you’d find in InDesign when it comes to page layout. These particular applications
have recently moved from PostScript-based VDP to a more modern HTML5 and CSS (cascading