Bitmap fonts and scalable fonts (Printer Basics)
computer font (or fount) is an electronic data file containing a set of glyphs, characters, or symbols such as dingbats. Although the term font first referred to a set of metal type sorts in one style and size, since the 1990s most fonts are digital, used on computers. There are three basic kinds of computer font file data formats:
Bitmap fonts consist of a series of dots or pixels representing the image of each glyph in each face and size. A bitmap font stores each character as a picture made of a pattern of dots. The basic disadvantage of bitmap fonts is that the fonts are only available for a defined size. If the size of a bitmap font is changed the original typeface is destroyed, for example, if a bitmap font is scaled up, the edges of the letters or symbols become jagged.
Outline fonts or vector fonts are collections of vector images, i.e. a set of lines and curves to define the border of glyphs. Early vector fonts were used by vector monitors and vector plotters using their own internal fonts, usually with thin single strokes instead of thick outlined glyphs. Outline fonts (also called vector fonts) use Bézier curves, drawing instructions and mathematical formulas to describe each glyph, which make the characer outlines scalable to any size.
A glyph’s outline is defined by the vertices of individual strokes and stroke’s profile. Its advantages over outline fonts include reducing number of vertices needed to define a glyph, allowing the same vertices to be used to generate a font with a different weight, glyph width, or serifs using different stroke rules, and the associated size savings. In essence, stroke-based fonts are small, scaleable, updateable, and customizable — and give developers the chance to deliver excellent looking text to Chinese, Japanese, and Korean customers anywhere.
The benefits of stroke-based fonts are:
- Compact format
- Updateable code
- Variable weight (light to bold, and anything in between)
- High-quality, scaleable output
- The ability to optimize the rendered characters for various output devices
- The ability to deploy one unified, stroke-based font in all of a developer’s products