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A micro JS library for manipulating and animating SVG.

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wout/svg.onchain.js

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svg.onchain.js

A micro JS library (362 bytes) for manipulating and animating SVG.

This library is intended for use in environments where the available storage space is very limited; like blockchains for example. Everything is stripped down to the bare essentials.

GitHub GitHub tag (latest SemVer) GitHub Workflow Status

Why not use vanilla JS?

Building an SVG document with plain JS is pretty verbose. Let's look at the following example:

const ns = 'http://www.w3.org/2000/svg'
const svg = document.createElementNS(ns, 'svg')
svg.setAttribute('xmlns', ns)
svg.setAttribute('width', 100)
svg.setAttribute('height', 100)
document.body.appendChild(svg)
const rect = document.createElementNS(ns, 'rect')
rect.setAttribute('width', 100)
rect.setAttribute('height', 100)
rect.setAttribute('fill', '#f06')
rect.setAttribute('rx', 10)
rect.setAttribute('ry', 20)
svg.appendChild(rect)

That's the code to create an SVG canvas and draw a pink square on it. In comparison, doing the same using this library is a lot more consice:

const doc = SVG.doc(100, 100, document.body)
SVG.el('rect', doc, {width: 100, height: 100, fill: '#f06', rx: 10, ry: 20})

That's 98 bytes instead of 406, or roughly 75% less code. And the difference is only going to get bigger the more objects you add. Of course, this library takes up 362 bytes as well, but that's quickly compensated after adding a few more objects.

Usage

Create a canvas of 100x100 px:

let cvs = SVG.doc(100, 100, document.body)

Add a square, filling the canvas:

let rect = SVG.el('rect', cvs, {width: 100, height: 100})

Update the colour of the square:

SVG.at(rect, {fill: '#0fa'})

Animate the corner radius of the square:

SVG.el('animate', rect, {
  attributeName: 'rx',
  values: '0;50;0',
  dur: '5s',
  repeatCount: 'indefinite'
})

License

svg.onchain.js is licensed under the terms of the MIT License.