Measure per-letter dimension of text in JavaScript

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Measure per-letter dimension of text in JavaScript的配图
TL;DR: Create a Range, set proper start and end points up to the text node with proper offset, then use Range.getBoundingClientRect() to get the dimensions. As a part of the Lyricova Jukebox, we wanted to support inline karaoke swipe animation. With the time tags in the data, it is easy to figure ou……