Microsoft VOLT

Microsoft Visual OpenType Layout Tool (VOLT) is a free, professional tool with a graphical user interface used to add high-level OpenType layout tables to fonts with TrueType outlines. It allows you to implement complex typographic logic like ligatures, contextual alternates, small caps, and precise glyph positioning without forcing you to write raw, compiled OpenType code.

The tool is widely used for creating cross-platform western typography and complex scripts like Arabic, Devanagari, and Bengali. Key Workflow Concepts

Using VOLT to build an OpenType font follows a structured project tree hierarchy:

Scripts: The writing system you are designing for (e.g., Latin, Arabic, Devanagari).

Language Systems: Sub-segments within a script (e.g., standard default or a specific language variant).

Features: The typographic rules triggered by an application (e.g., liga for standard ligatures, smcp for small caps).

Lookups: The literal mathematical substitutions and positional calculations tied to those features. Step-by-Step Guide to Using VOLT 1. Preparing and Importing the Font

Start with a Base Font: Generate your standard TrueType font (.ttf) using a font editor like FontLab, FontCreator, or Glyphs. Ensure all your glyphs are properly named.

Open the Font: Launch VOLT and go to File > Open Font. Select your base font. VOLT stores project data dynamically inside private, temporary layout tables in the font file itself while you work. 2. Defining Glyph Groups

Grouping makes mapping rules much faster. Instead of creating a rule for every character, you can create a single rule for an entire group.

Create Groups: Define lists like VOWELS, CONSONANTS, or SMALL_CAPS to reference globally throughout your rules. 3. Building the Feature Tree

Navigate to the main project window to construct your architecture.

Add Scripts & Languages: Input tags following the system ‘name ’ (e.g., Latin ).

Assign Features: Assign standard OpenType feature tags (like ) to the corresponding language. 4. Writing Substitutions (GSUB) and Positioning (GPOS)

OpenType logic is split into two primary components that you will program inside VOLT: Visual OpenType Layout Tool – Typography – Microsoft Learn