Editor’s Note: This article is part of the Adobe Acrobat 6.0 Learning Center
The new Layers functionality, technically known as Optional Content
Groups, opens up a new world of exciting possibilities. Engineers and
architects can start to use this feature with the release of Acrobat 6
Professional, for others it will come over time as companies, including Adobe
Systems, add support so that their files can be converted to PDF with
layers intact. Expect to see a rich variety of solutions over the next few
years as third-party developers see how they can utilize the support now
available in the latest 1.5 PDF specification. At release there are three ways
to create Optional Content Groups (layers):
- AutoCAD – via the new PDFMaker macro for AutoCAD
- Visio – via the new PDFMaker macro for Visio
- PDFMarks – using them with Acrobat Distiller
For engineers and architects the introduction of layer support now makes Acrobat
6 Professional a feasible part of their workflow. AutoCAD files typically
contain numerous layers — e.g for architects they might contain one for each
of plumbing, electrical, ventilation, emergency lighting, and so on. In the
past, if an architect wished to share some of their work in a PDF file they
would need to create a separate PDF file (or at least a page) for each layer
within the AutoCAD file.
See above the original file in AutoCAD. The user adds the layers and layer sets
to be included in the PDF.
See above the converted PDF file in Acrobat 6. The Layers tab appears down the
left side. Layer creation is exclusive to Acrobat 6 Professional, while viewing
them can be done on both Standard and Professional.
As creative professionals would be well aware, Adobe Illustrator, Photoshop and
InDesign all support their own forms of layers. As with the release of Tagged
PDF with Acrobat 5.0, it’s currently not possible to create PDF files that
support layers out of the box with Acrobat 6 Professional and Adobe InDesign,
Adobe Illustrator and Adobe PhotoShop. However, you would expect that we could
expect to see support for this feature as these professional publishing tools
are revised, reworked and released in the future.
It’s easy to start thinking about how layers might be used in the future:
- Creating a rich master document that contains a number of alternative page
representations. These could be high-resolution, low-resolution, different
layouts, or perhaps even a more accessible version.
Cartographers might use layers within PDF file to allow additional detail to be
shown on demand. For example, a plug-in could be written which only showed
certain layers at zoom levels greater than 150%. These high quality maps could
use layers to display different information such as topography, names,
Professional publishers might look to use layers as a method of storing their
page separations in one convenient location.
- Use layers in tables and charts to turn on/off different parts of information.
We like to think of Optional Content Groups as being a rich addition to the
infrastructure of PDF, that will be expanded upon in unique and exciting ways
over the coming months and years by both Adobe Systems themselves, and the rich
set of third-party plug-in developers.