EVEN as the web scintillates in a rainbow of colours, digital fonts persist in a monochromatic past resembling the long-gone era of wood and metal type. This may at last be about to change. A new standard, backed by Microsoft and incorporated into its Windows 8.1 release, will allow true, infinitely resizeable multicoloured type on the internet, in apps and even for home colour printers. The firm's proposal is the furthest along of those solicited by a standards body that will harmonise propsals into a final specification. (For the uninitiated: a typeface is the design; a font is its instantiation in a particular set of characters; type refers to characters in a font, whether letters, punctuation or esoteric symbols.)
Operating systems (OSs) display two kinds of image objects: bitmaps and vectors. Bitmapped fonts, just as photographs or other graphics, will either show jagged edges (become stairstepped or "pixellated") or become blurry when sized larger than an exact pixel-for-pixel mapping between the bitmap file and the display. Details that look fine at an intended size appear grotesque or coarse when enlarged. When shrunk, bitmaps may become illegible or muddy.
Vectors are mathematical representations of the arcs and straight-line segments. These can make up a letter or symbol. The advantage of vectors is an independence from the resolution (the number of pixels per inch) of a display device. Vector graphics or type may be scaled and rendered ("rasterised") as smoothly as the density of a screen's grid permits. (Most vector graphics rely on rapidly computable Bézier curves, if you really must know.)
Digital fonts began their lives in the 1960s as something akin to bitmaps. Then came Adobe Systems, with its founding innovation: an efficient way to switch from bitmap to vector. This helped desktop publishing replace traditional typesetting and page composition starting in the 1980s. However, from Adobe's PostScript format to the latest industry-wide OpenType standard, the characters in a font can be assigned just about any colour, but remain obstinately monochromatic.
A multi-coloured character meanwhile, tends to be a mish-mash of vectors and bitmaps. In Apple's Mac OS update from 2012, say, emoji icons comprise symbols created in a vector program and then rasterised into multiple fixed-sized bitmaps. When the emoji is shrunk or enlarged, the closest bitmap size is chosen and modified. Enlarge too far, rotate or otherwise manipulate the image, though, and the bitmaps' limitations show.
One existing way to avoid bitmap duplication is digitally to mimic an old printing technique used with "chromatic" fonts. With larger sizes of type cut from end-grain wood, a designer would make separate pieces for each colour that fit within the same character shape. As a result, the body of a letter or number could appear in one colour while an outline, shadow or differently coloured box surrounding the character could appear in one or more others. A pressman would load the first element of the type in a frame, run through all the printed sheets in one colour of ink, swap out the other part of the font, and repeat with the next colour of ink using the same sheets. Alignment was critical.
A pressman had physical components that, printed one after another, resulted in a single letter in multiple colours; digital designers likewise have these separate components, almost the same as their physical equivalents, that a type designer has divided up across a vector font. In both cases, the process was laborious and finicky.
For instance, in a typeface with a shadow behind each letter, a typeface's designer would break each character apart into one version with just a shadow and outline, and another drawn to fit within that outline, just as in this 1854 typeface, Doric Shade. Using software like Adobe's Illustrator or InDesign, he then assembles a layer for each kind of component: one for the shadow and outline and another for the shape that fills that outline. When stacked up and aligned properly, the multi-colour letter appears. However, this approach only works well for layouts designed for printing, whether at a press or on a home or office printer. It is possible with some tinkering to make it work in some web browsers, but not all of them.
Microsoft's new approach also takes the chromatic-font tack, minus the fiddly bits. Its new standard (built into Windows 8.1) removes the tedium of selection, assembly and alignment. It will still rely on OpenType, which it and Adobe developed to be flexible and which is used by all OSs. OpenType treats every character in a font file almost like a folder of possible appearances. In the days of wood and metal, many headline typefaces were designed to have several alternatives for most of the capital letters. OpenType allowed type designers to do the same with digital type. For instance, a capital "T" might exist in a font in its plain, staid version, but also in one with a swash or calligraphic flourish to use as the first or final letter in large type. OpenType organises all of the alternatives for "T" in such a way that software like InDesign allows a designer to select the letter and see all his options.
Microsoft will extend OpenType by adding multi-coloured characters. Each colourful letter or symbol will be a set of layers, perfectly aligned and already specified for hue, in a new kind of OpenType alternate character. A designer will be able to pick a polychromatic letter just as easily as he can select a swashbuckling "T" today. A lot of layout software and web browsers will need to be modified to grab the layers, colour them according to the type designer's instructions and overlay them. However, the new standard will be compatibe with older software: every colourful letter will have a monochrome version that dated programs understand.
There has been some niche interest in chromatic type for years, says Greg Hitchcock, the new format's architect at Microsoft. But the issue has really come to the fore only as websites began creating custom fonts that contain special characters with specific functions, like a shopping cart or a logo, that look just as crisp on a smartphone and a large desktop monitor. The new standard will allow a richness of colour as if the items were bitmap drawings, but with the scalability of vectors. (Mr Hitchcock, a 27-year veteran of Microsoft, says a similar trick was employed as far back as Windows 95, where hidden custom fonts were used to create good-looking elements in the OS's interface, such as a close box or window-resizing handle.)
Websites could only use such custom fonts in the last two years, as internet users upgraded to browsers that reliably download and display vector typefaces (whether licensed from digital font foundries or developed by a website) other than those built into the OS on which the browser was installed. To make their icons and other symbols appear in multiple colours, websites have had to use either coding calisthenics to align the pieces or rely on advanced formatting that some browsers still lack.
The new approach will require no extra effort on the part of someone designing a document or a webpage to use. Microsoft's fonts head, Simon Daniels, gushes that, as a result, custom fonts hitherto limited to professional designers will now be available to the average user. Let a thousand colours bloom.
(Image credit: A specimen designed by Microsoft using typefaces from Linotype, Monotype, The Font Bureau, the Hamilton Wood Type Foundry and P22, and FontFont.)
