Editing Computer font (section)

=== <span class="anchor" id="OUTLINE"></span>Outline fonts ===
''Outline fonts'' or ''vector fonts'' are collections of [[vector graphics|vector images]], consisting of lines and curves defining the boundary of [[glyphs]]. Early vector fonts were used by [[vector monitor]]s and [[plotter|vector plotters]] using their own internal fonts, usually with thin single strokes instead of thickly outlined glyphs. The advent of desktop publishing brought the need for a common standard to integrate the [[graphical user interface]] of the first [[Macintosh]] and [[laser printer]]s. The term to describe the integration technology was [[WYSIWYG]] (What You See Is What You Get). This common standard was (and still is{{when|date=September 2021}}) Adobe [[PostScript]].{{citation needed|date=September 2021}} Examples of outline fonts include: PostScript [[Type 1 and Type 3 fonts]], [[TrueType]], [[OpenType]] and [[Compugraphic]].

The primary advantage of outline fonts is that, unlike [[bitmap fonts]], they are a set of lines and curves instead of pixels; they can be scaled without causing [[pixelation]]. Therefore, outline font characters can be scaled to any size and otherwise transformed with more attractive results than bitmap fonts, but require considerably more processing and may yield undesirable rendering, depending on the font, rendering software, and output size. Even so, outline fonts can be transformed into bitmap fonts beforehand if necessary. The converse transformation is considerably harder since bitmap fonts require a [[heuristic algorithm]] to guess and approximate the corresponding curves if the pixels do not make a straight line.

Outline fonts have a major problem, in that the [[Bézier curve]]s used by them cannot be rendered accurately onto a raster display (such as most computer monitors and printers), and their rendering can change shape depending on the desired size and position.<ref>{{cite web |title = The raster tragedy at low resolution |url = http://www.microsoft.com/typography/tools/trtalr.aspx |author = Stamm, Beat |website = [[Microsoft]] |date = 1998-03-25 |access-date = 2015-08-10 |archive-url = https://web.archive.org/web/20160219231632/http://www.microsoft.com/typography/tools/trtalr.aspx |archive-date = 2016-02-19 |url-status = dead }}</ref> Measures such as [[font hinting]] have to be used to reduce the visual impact of this problem, which requires sophisticated software that is difficult to implement correctly. Many modern desktop computer systems include software to do this, but they use considerably more processing power than bitmap fonts, and there can be minor rendering defects, particularly at small font sizes. Despite this, they are frequently used because people often consider the ability to freely scale fonts, without incurring any pixelation, to be important enough to justify the defects and increased [[computational complexity]]. These issues are however mostly solved by antialiasing (as described in [[font rasterization]]) and the high display resolutions that are commonly in use today.