Author: David Turner

# FreeType Glyph Conventions

## Version 2.1

### Copyright 1998-2000 David Turner (david@freetype.org)
Copyright 2000 The FreeType Development Team (devel@freetype.org)

This document presents the core conventions used within the FreeType library to manage font and glyph data. It is a must-read for all developers who need to understand digital typography, especially if you want to use the FreeType 2 library in your projects.
## Table of Contents
## I. Basic Typographic Concepts ### 1. Font files, format and information 2. Character images and mappings 3. Character and font metrics ## II. Glyph outlines ### 1. Pixels, points and device resolutions 2. Vectorial representation 3. Hinting and bitmap rendering ## III. Glyph metrics ### 1. Baseline, pens and layouts 2. Typographic metrics and bounding boxes 3. Bearings and advances 4. The effects of grid-fitting 5. Text widths and bounding box ## IV. Kerning ### 1. Kerning pairs 2. Applying kerning ## V. Text processing ### 1. Writing simple text strings 2. Sub-pixel positioning 3. Simple kerning 4. Right-to-left layouts 5. Vertical layouts 6. WYSIWYG text layouts ## VI. FreeType Outlines ### 1. FreeType outline description and structure 2. Bounding and control box computations 3. Coordinates, scaling, and grid-fitting ## VII. FreeType bitmaps ### 1. Vectorial versus pixel coordinates 2. FreeType bitmap and pixmap descriptor 3. Converting outlines into bitmaps and pixmaps