103 lines
3.2 KiB
HTML
103 lines
3.2 KiB
HTML
<!doctype html public "-//w3c//dtd html 4.0 transitional//en"
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"http://www.w3.org/TR/REC-html40/loose.dtd">
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<html>
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<head>
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<meta http-equiv="Content-Type"
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content="text/html; charset=iso-8859-1">
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<meta name="Author"
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content="David Turner">
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<title>The Design of FreeType 2 - Introduction</title>
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</head>
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<body text="#000000"
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bgcolor="#ffffff">
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<h1 align=center>
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The Design of FreeType 2
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</h1>
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<center>
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<table width="75%">
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<tr><td>
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<table width="100%">
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<tr bgcolor="#ccccee"><td>
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<h1>
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Introduction
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</h1>
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</td></tr>
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</table>
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<p>This document provides details on the design and implementation of the
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FreeType 2 library. Its goal is to allow developers to better
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understand the way how FreeType 2 is organized, in order to let them
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extend, customize, and debug it.</p>
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<p>Before anything else, it is important to understand the
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<em>purpose</em> of this library, i.e., why it has been written:</p>
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<ul>
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<li>
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<p>It allows client applications to <em>access font files easily</em>,
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wherever they could be stored, and as independently of the font format
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as possible.</p>
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</li>
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<li>
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<p>Easy <em>retrieval of global font data</em> most commonly found in
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normal font formats (i.e. global metrics, encoding/charmaps,
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etc.).</p>
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</li>
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<li>
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<p>It allows easy <em>retrieval of individual glyph data</em>
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(metrics, images, name, anything else).</p>
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</li>
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<li>
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<p><em>Access to font format-specific "features"</em> whenever
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possible (e.g. SFNT tables, Multiple Masters, OpenType Layout tables,
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etc.).</p>
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</li>
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</ul>
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<p>Its design has also severely been influenced by the following
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requirements:</p>
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<ul>
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<li>
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<p><em>High portability</em>. The library must be able to run on any
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kind of environment. This requirement introduces a few drastic
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choices that are part of FreeType 2's low-level system
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interface.</p>
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</li>
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<li>
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<p><em>Extendability</em>. New features should be added with the
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least modifications in the library's code base. This requirement
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induces an extremely simple design where nearly all operations are
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provided by modules.</p>
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</li>
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<li>
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<p><em>Customization</b>. It should be easy to build a version of the
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library that only contains the features needed by a specific project.
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This really is important when you need to integrate it in a font
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server for embedded graphics libraries.</p>
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</li>
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<li>
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<p><em>Compactness</em> and <em>efficiency</em>. The primary target
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for this library are embedded systems with low cpu and memory
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resources.</p>
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</li>
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</ul>
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<p>The rest of this document is divided in several sections. First, a few
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chapters will present the library's basic design as well as the
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objects/data managed internally by FreeType 2.</p>
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<p>A later section is then dedicated to library customization, relating
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such topics as system-specific interfaces, how to write your own module
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and how to tailor library initialization & compilation to your needs.</p>
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</td></tr>
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</table>
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</center>
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</body>
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</html>
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