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</li></ul></li><li class="nav-list-item "><a href="/graphite_codeSnippets.html" class="nav-list-link">GDL Code Snippets</a></li><li class="nav-list-item "><a href="/graphite_devApp.html" class="nav-list-link">Adding Graphite to Your Application</a></li></ul></li><li class="nav-list-item"><a href="/graphite_download.html" class="nav-list-link">Download</a></li><li class="nav-list-item"><a href="/graphite_support.html" class="nav-list-link">Support</a></li><li class="nav-list-item"><a href="/graphite_contact.html" class="nav-list-link">Contact</a></li></ul> </nav> <footer class="site-footer"> This site uses <a href="https://github.com/just-the-docs/just-the-docs">Just the Docs</a>, a documentation theme for Jekyll. </footer> </div> <div class="main" id="top"> <div id="main-header" class="main-header"> <div class="search" role="search"> <div class="search-input-wrap"> <input type="text" id="search-input" class="search-input" tabindex="0" placeholder="Search Graphite site" 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aria-hidden="true"><use xlink:href="#svg-link"></use></svg></a> Font Development </h1> <h2 id="overview"> <a href="#overview" class="anchor-heading" aria-labelledby="overview"><svg viewBox="0 0 16 16" aria-hidden="true"><use xlink:href="#svg-link"></use></svg></a> Overview </h2> <p>Adding Graphite support to a font involves:</p> <ol> <li>writing a program using Graphite Description Language (GDL) describing the behavior of the font</li> <li>compiling the program along with the font to create the Graphite-enabled version of the font</li> <li>testing and debugging your smart font using a Graphite-enabled application</li> </ol> <blockquote class="blue-note"> <p>To add Graphite support to a font, the font’s license must grant you permission to modify it.</p> </blockquote> <h3 id="1-the-gdl-program"> <a href="#1-the-gdl-program" class="anchor-heading" aria-labelledby="1-the-gdl-program"><svg viewBox="0 0 16 16" aria-hidden="true"><use xlink:href="#svg-link"></use></svg></a> 1. The GDL program </h3> <p>GDL is a programming language that describes the “smart” behavior of the font. It is written to correspond to a specific font, and includes definitions of the glyphs in the font and rules describing their behavior.</p> <p><a href="assets/resources/GDL.pdf" class="btn btn-blue">Download GDL documentation</a></p> <p>The following tools can be used to assist in the development of a GDL program:</p> <ul> <li>make_gdl.pl - a Perl utility that automatically generates some of the necessary GDL code from a font and an XML file of attachment point data. This is included in the SIL <a href="https://scripts.sil.org/FontUtils" target="_blank">↗ FontUtils</a> package.</li> <li>FLWriteXml.py - a Python utility that outputs a file of attachment points from FontLab, which can then be used by make_gdl to define attachment points for Graphite. This file can be downloaded from the <a href="https://github.com/silnrsi/pysilfont" target="_blank">↗ SIL Font Utility GitHub repository</a>.</li> </ul> <h3 id="2-compiling-the-program"> <a href="#2-compiling-the-program" class="anchor-heading" aria-labelledby="2-compiling-the-program"><svg viewBox="0 0 16 16" aria-hidden="true"><use xlink:href="#svg-link"></use></svg></a> 2. Compiling the program </h3> <p>The Graphite compiler takes as input the original font and the GDL program, and outputs a new version of the font with the GDL code converted into special-purpose TrueType tables. These tables are used by the Graphite engine to perform smart rendering.</p> <p>The Windows executable can be downloaded <a href="https://scripts.sil.org/GraphiteCompilerDownload" target="_blank">↗ here</a>.</p> <p>For Linux systems, the source for the grcompiler program is available from <a href="http://sourceforge.net/projects/silgraphite/files/grcompiler" target="_blank">↗ here</a>. You can install it using the package manager: <code class="language-plaintext highlighter-rouge">sudo apt install grcompiler</code>.</p> <h3 id="3-testing-the-font"> <a href="#3-testing-the-font" class="anchor-heading" aria-labelledby="3-testing-the-font"><svg viewBox="0 0 16 16" aria-hidden="true"><use xlink:href="#svg-link"></use></svg></a> 3. Testing the font </h3> <p>You can test your font using any <a href="graphite_apps">Graphite-enabled application</a>. In order to do so, the most recently compiled version of the font must be properly installed according to the requirements of the operating system. You must also have a way to provide the specific Unicode characters–a keyboard, existing datafile, etc.</p> <p>If you discover errors in the behavior of the Graphite font, modify the GDL program, recompile, reinstall the output font, and retest.</p> <h2 id="graide"> <a href="#graide" class="anchor-heading" aria-labelledby="graide"><svg viewBox="0 0 16 16" aria-hidden="true"><use xlink:href="#svg-link"></use></svg></a> Graide </h2> <p><a href="graide">Graide</a> is a tool for creating Graphite fonts. Version 1.0 is available.</p> <h2 id="tutorial"> <a href="#tutorial" class="anchor-heading" aria-labelledby="tutorial"><svg viewBox="0 0 16 16" aria-hidden="true"><use xlink:href="#svg-link"></use></svg></a> Tutorial </h2> <p>The following is a tutorial to help you learn to program using GDL. It includes instructions for using Graide (GRAphite Integrated Development Environment):</p> <p><a href="graide_tutorial">GDL Tutorial</a></p> <h2 id="gdl-code-snippets"> <a href="#gdl-code-snippets" class="anchor-heading" aria-labelledby="gdl-code-snippets"><svg viewBox="0 0 16 16" aria-hidden="true"><use xlink:href="#svg-link"></use></svg></a> GDL code snippets </h2> <p>The following small examples can be a useful reference as you develop your Graphite font.</p> <p><a href="graphite_codeSnippets">Code snippets</a></p> </main> <hr> <footer> <p class="text-small text-grey-dk-100 mb-0">Copyright © 2012-2023 SIL International and released under the <a href="http://creativecommons.org/licenses/by-sa/3.0/">Creative Commons Attribution-ShareAlike 3.0 license (CC-BY-SA)</a> unless noted otherwise.</p> </footer> </div> </div> <div class="search-overlay"></div> </div> </body> </html>