Microsoft Typography
February 2002

This document presents information that will help font developers create or support OpenType fonts for all "standard" scripts covered by the Unicode Standard, for example: Latin, Cyrillic, Greek and Armenian.

This is a multi-page specification. To access specific pages, use the Contents section below, or the navigation bar at the bottom of each page.

Contents

• Introduction
• Shaping Engine
• Features
• Appendix

Introduction

In this document, "standard" refers to any non-complex script, that is, any script that does not require re-ordering or contextual analysis. See the Appendix for a list of scripts and languages.

Font developers will learn how to encode script features in their fonts, choose character sets, organize font information, and use existing tools to produce standard script fonts. Registered features of standard scripts are defined and illustrated, encodings are listed, and templates are included for compiling layout tables for OpenType fonts.

This document also presents information about the standard OpenType shaping engine of Uniscribe, an operating system component responsible for text layout.

In addition to being a primer and specification for the creation and support of standard script fonts, this document is intended to more broadly illustrate the OpenType Layout architecture, feature schemes, and operating system support for shaping and positioning text.

Glossary

The following terms are useful for understanding the layout features and script rules discussed in this document.

Base Glyph - Any glyph that can have a diacritic mark above or below it. Layout operations are defined in terms of a base glyph, not a base character, as a ligature may act as the base.

Character - Each character represents a Unicode character code point. For example the 'A' character is U+0041. A character may have multiple forms of glyphs.

Diacritic Marks - A character that is positioned above or below a character to provide pronunciation guidance (i.e. accent acute, grave, tilde, etc.)

Glyph - A glyph represents a form of one or more characters.

Ligature - A combination of glyphs that join to form a single glyph. It is up to the font designer to create the ligatures as he deems best for the font he is working with.

Standard Script - Any non-complex script; any script that does not require re-ordering or contextual analysis in the shaping process.