glyphbased

Glyphbased, often written as glyph-based, is a term used in typography and digital text processing to describe approaches, systems, or representations that treat glyphs as the primary unit of text rather than abstract code points. A glyph is a specific visual shape that represents a character or a set of characters depending on the font. In a glyph-based pipeline, rendering involves mapping input text to a sequence of glyphs, applying substitutions, ligatures, and diacritic placement at the glyph level.

In font technology, fonts contain a repertoire of glyphs, and shaping engines determine which glyphs to display for a given string. This process can involve complex rules for substitution (such as ligatures or contextual forms) and precise positioning to achieve typographic accuracy. While code points and grapheme clusters remain important for indexing and text manipulation, the visual output is governed by glyphs.

The glyph-based view contrasts with strictly code-point oriented processing, though modern text rendering generally integrates both perspectives. It is particularly relevant for languages with complex scripts, where multiple glyphs may correspond to a single character, and for logographic systems where each glyph represents a visual unit of meaning.

Applications of glyph-based approaches appear in digital typography, font design, typesetting, and rendering engines, as well as in optical character recognition and handwriting recognition, where recognizing or selecting the appropriate glyph shape is central. OpenType exemplifies glyph-based operations through features like substitutions (GSUB) and positioning (GPOS). The term is commonly used as a descriptive label rather than a product name.