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<main>
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<h1 id="font-rendering"><a class="header" href="#font-rendering">Font Rendering</a></h1>
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<p>There exists no universally perfect solution to font rendering. Depending on the runtime environment a method needs to
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be chosen. <a href="https://stackoverflow.com/a/5278471">This StackOverflow post</a> outlines some state-of-the-art methods. Some
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more approaches are described <a href="https://aras-p.info/blog/2017/02/15/Font-Rendering-is-Getting-Interesting/">here</a>.</p>
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<p>From my perspective the following approaches could work potentially:</p>
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<ol>
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<li>Tessellate Fonts</li>
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<li>SDF Font Rendering</li>
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<li>GPU Text Rendering directly from Bezier Curves</li>
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<li>Draw text using a Web Canvas and load them to GPU</li>
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</ol>
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<p>There is a thesis which summarizes some methods <a href="https://lup.lub.lu.se/luur/download?func=downloadFile&recordOId=9024910&fileOId=9024911">here</a>.
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A link collection about font related projects can be viewed <a href="../appendix/link-collection.html#font-rendering">here</a>.</p>
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<h2 id="approaches"><a class="header" href="#approaches">Approaches</a></h2>
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<h3 id="tessellate-fonts"><a class="header" href="#tessellate-fonts">Tessellate Fonts</a></h3>
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<p>There is <a href="https://github.com/fetisov/ttf2mesh">ttf2mesh</a> which generates meshes. I was already able to generate about 1k
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glyphs with ~40FPS.</p>
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<h3 id="sdf-font-rendering"><a class="header" href="#sdf-font-rendering">SDF Font Rendering</a></h3>
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<p>There is a blogpost by Mapbox <a href="https://blog.mapbox.com/drawing-text-with-signed-distance-fields-in-mapbox-gl-b0933af6f817">here</a>.
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Some more implementation documents are available <a href="https://github.com/mapbox/mapbox-gl-native/wiki/Text-Rendering">here</a>.
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A good foundation for SDF fonts was created by Chlumsky with <a href="https://github.com/Chlumsky/msdfgen">msdfgen</a>.</p>
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<h3 id="gpu-text-rendering-from-bezier-curves"><a class="header" href="#gpu-text-rendering-from-bezier-curves">GPU Text Rendering from Bezier Curves</a></h3>
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<p>The solutions exist:</p>
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<ul>
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<li><a href="https://wdobbie.com/post/gpu-text-rendering-with-vector-textures/">By Will Dobbie</a> with an
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implementation <a href="https://github.com/azsn/gllabel">here</a></li>
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<li><a href="http://sluglibrary.com/">Slug Library</a> which is patented and probably therefore not usable</li>
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</ul>
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<p><a href="https://jcgt.org/published/0006/02/02/paper.pdf">Here</a> is the whitepaper of the Slug library. There is also
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a <a href="http://sluglibrary.com/slug_algorithm.pdf">poster</a> about it. There also exists
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an <a href="https://github.com/mightycow/Sluggish">open implementation</a>.</p>
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<h3 id="draw-text-using-a-web-canvas"><a class="header" href="#draw-text-using-a-web-canvas">Draw text using a Web Canvas</a></h3>
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<p>This approach has the downside that we can not dynamically scale rendered fonts according to the current zoom level.</p>
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<h2 id="other-approaches"><a class="header" href="#other-approaches">Other Approaches</a></h2>
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<ul>
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<li><a href="https://superluminal.eu/16x-aa-font-rendering-using-coverage-masks-part-iii/">16x AA font rendering using coverage masks</a></li>
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