OpenType.js

Font creation technologies have so far largely been written in C or Python and offered to users as desktop applications or command line tools. Since 2014, the library OpenType.js has been able to parse and generate OpenType fonts in environments supporting JavaScript. This opens up exciting possibilities for detailed control over all of aspects of typography on the web.

OpenType.js is used in a number of popular open-source and commercial tools such as p5.js, Prototypo, FontSelf and Metapolator.

http://opentype.js.org/

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