THE OPENTYPE EXPERIENCE - PART 1

13 November 2006
Thomas Phinney
Thomas Phinney

Part one of two

The dominance of Type 1 and TrueType formats has now been challenged by the limitless and simple interplay of characters offered by OpenType. The democratization of typography and of desktop editing that took place in the eighties would appear to have its correspondence in what could be further progress in the availability of possible uses. In theory, OpenType controls all aspects and optimizes an infinite number of alternatives for forming words.

Put simply, OpenType is a font format that allows for advanced typographic features and extended language support, in a single cross-platform font file. Typesetting that would have taken several different fonts can now be done with formatting changes and a single font, on both Mac OS and Windows.

Here's an example of the workflow that OpenType can help enable:

You look at the document your colleague just passed you, along with the fonts she used on her Windows laptop. On your Macintosh you load the font files she sent, and open the document. Viewing the layout, you decide that you'd like to see how it looks with a different font, so you do a single replace operation to change the font she used to a different one. All the oldstyle numbers and small caps in the document, and the swashes in the titles, automatically change as well. You work on the layout, and redefine the styles to turn on automatic ligatures throughout the document, getting not only fi and fl, but a full set of typographic ligatures such as ffi.

Later, when the job is done, you export the text to HTML or XML, and the resulting document has the correct text: even the ffi ligatures have automatically decomposed to their underlying characters.


This isn't some imaginary future. The workflow described above is here today for people who use OpenType fonts with the applications that support them well. Even with less savvy applications, users get the benefits of cross-platform font files and single-file fonts. With applications that understand OpenType layout features, they can do much more. Users can achieve typographic effects such as true small caps, oldstyle figures, ligatures, and more, via formatting rather than by switching fonts.

The origins of OpenType
To understand what OpenType is, it helps to understand where it comes from, and more about the problems it tries to solve. This requires a brief look at the history of font formats in the last twenty years.

PostScript and desktop publishing, there were no standards for digital fonts. Various companies made computerized typesetting systems, each of which used its own proprietary hardware and software for everything, including fonts. So the fonts made by "Company A" would only work with the hardware and software from "Company A," and not with anybody else's equipment.

At the same time, many of these digital fonts used bitmaps (dots) rather than outlines (vectors). Although the use of bitmaps allowed for great fine tuning, it meant that a separate font was needed for each size it was intended to be used at, or else it would not look as good. Outline fonts were scalable, but to make them look good at lower resolutions, extra information needed to be put into the fonts to help the renderer preserve key features at lower resolutions. Making outlines work well at a wide range of sizes was difficult and expensive enough that many developers didn't even try, and stuck with bitmaps instead.

In the early 1980s, Adobe developed the PostScript printer language, which became an integral part of the desktop publishing revolution. The PostScript language specification was itself public, so that anyone could write PostScript programs and software. For a fee, Adobe would also license its PostScript interpreter to anyone who wanted to make a printer or imagesetter. The language also included specifications for fonts, but unlike the language in general, the PostScript Type 1 format was initially Adobe's secret. The public font specification was the Type 3 format, which although more flexible, lacked the "hinting" features of the Type 1 format that made it work better on lower-resolution devices.

TrueType and the Font Wars of the 1990s
Apple saw the need to have scalable fonts built into its operating system, not only for printing, but also for use on screen. But Adobe would have asked for large licensing fees for its Type 1 technology, it was optimised more for print resolutions than on-screen display, and they still would not have had ownership and control of the technology. So Apple started developing its own technology, which became TrueType. Microsoft saw similar needs, and entered into a cross-licensing deal with Apple. They jointly announced TrueType in 1991, and introduced it into their operating systems shortly thereafter.
In response, Adobe released the long-secret specification for Type 1, and created an add-on program, called Adobe Type Manager (ATM), which would make Type 1 fonts scalable for on-screen display, just like TrueType.

Like Type 1, TrueType uses outlines to describe the glyphs (a "glyph" is a shape for a character in a specific font). It uses scalable fonts which can be viewed on-screen or printed to just about any device. However, TrueType differs from Type 1 in several major ways. The outlines use a different kind of math. The data structures use a table approach, which makes them extensible for future needs. Most importantly, TrueType instructions similar to the "hinting" of Type 1 fonts are very powerful, and can optimise the outlines for lower resolutions, particularly on-screen, with so much control that specific bitmap patterns can be produced.

Although Type 1 and TrueType both work on Mac and Windows, each font format has historically required platform-specific packaging, so that a given font file could not be used as-is on both platforms.

Despite some apparent advantages for TrueType, Type 1 remained the standard for publishing and professional graphics, especially on the Macintosh. Meanwhile, TrueType did very well with business and home users, and was particularly popular on Windows. This difference can be attributed to various factors, but almost all of them went away over time.

The traditional dominance of Type 1 for the print and design industry now has much more to do with inertia and superstition than any current problems with TrueType. All the major players try to make all font types work well with their software and operating systems. The basic rendering functionality of the original ATM software is built into both the Mac OS and Windows, so that Type 1 fonts function alongside OpenType and TrueType fonts.

Introducing OpenType
How did we get to this state of detente? In late 1996, Adobe and Microsoft announced that they were trying to end the font wars by creating a single font format that would allow for the best features of both Type 1 and TrueType, as well as extending their capabilities to deal with the limitations of the old formats. The new format was to be called OpenType. ...


In Part 2 of The OpenType Experience...

The OpenType format, plus layout features, type support and the future of OpenType.



About this article
This article was previously published in tipoGrafica 62, year XVIII, August, September, 2004, p. 28 to 33. Translated from Spanish by Peggy Jones and Martin Schmoller.

About Thomas Phinney

Thomas Phinney is a frequent conference speaker and occasional writer who is involved in the technical, artistic, historical and business aspects of type, with a special concern for the issues experienced by end users. He has worked in Adobe's type group for six years, currently as fonts programme manager. Phinney has a Master's degree in graphic arts publishing, specializing in typography and design, from the Rochester (NY) Institute of Technology, and a Master's of business administration from the University of California at Berkeley.