modern-screenshot

Fast generates an image from a DOM node using HTML5 canvas and SVG

📦 Install

npm i modern-screenshot

🦄 Usage

import { domToPng } from 'modern-screenshot'

domToPng(document.querySelector('#app')).then(dataUrl => {
  const link = document.createElement('a')
  link.download = 'screenshot.png'
  link.href = dataUrl
  link.click()
})

CDN

<script src="https://unpkg.com/modern-screenshot"></script>
<script>
  modernScreenshot.domToPng(document.querySelector('body')).then(dataUrl => {
    const link = document.createElement('a')
    link.download = 'screenshot.png'
    link.href = dataUrl
    link.click()
  })
</script>

Browser Console

⚠️ Partial embedding will fail due to CORS

const script = document.createElement('script')
script.src = "https://unpkg.com/modern-screenshot"
document.getElementsByTagName('head')[0].appendChild(script)

script.onload = () => {
  modernScreenshot
    .domToImage(document.querySelector('body'), {
      debug: true,
      progress: (current, total) => {
        console.log(`${ current }/${ total }`)
      }
    })
    .then(img => {
      const width = 600
      const height = img.height * (width / img.width)
      console.log('%c ', [
        `padding: 0 ${ width / 2 }px;`,
        `line-height: ${ height }px;`,
        `background-image: url('${ img.src }');`,
        `background-size: 100% 100%;`,
      ].join(''))
    })
}

Methods

Such as domToPng(node, options)

DOM to dataURL

DOM to data

DOM to HTMLElement

Options

See the options.ts

Singleton context and web worker

Quick screenshots per second by reusing context and web worker

// use vite
import workerUrl from 'modern-screenshot/worker?url'
import { createContext, destroyContext, domToPng } from 'modern-screenshot'

async function screenshotsPerSecond() {
  const context = await createContext(document.querySelector('#app'), {
    workerUrl,
    workerNumber: 1,
  })
  for (let i = 0; i < 10; i++) {
    domToPng(context).then(dataUrl => {
      const link = document.createElement('a')
      link.download = `screenshot-${ i + 1 }.png`
      link.href = dataUrl
      link.click()
      if (i + 1 === 10) {
        destroyContext(context)
      }
    })
    await new Promise(resolve => setTimeout(resolve, 1000))
  }
}

screenshotsPerSecond()

See the context.ts

TODO

unable to clone closed shadowDom

input::placeholder { color: red; }
unable to clone css counters

content: counter(step);
unable to clone -webkit-scrollbar

body::-webkit-scrollbar-thumb { background-color: red; }

Other interesting packages

name	description
modern-gif	`GIF` decoder / encoder
dom-vcr	Generates an `MP4` or `GIF` from a DOM node