JavaScript preprocessors can help make authoring JavaScript easier and more convenient. For instance, CoffeeScript can help prevent easy-to-make mistakes and offer a cleaner syntax and Babel can bring ECMAScript 6 features to browsers that only support ECMAScript 5.
Any URL's added here will be added as <script>
s in order, and run before the JavaScript in the editor. You can use the URL of any other Pen and it will include the JavaScript from that Pen.
You can apply a script from anywhere on the web to your Pen. Just put a URL to it here and we'll add it, in the order you have them, before the JavaScript in the Pen itself.
If the script you link to has the file extension of a preprocessor, we'll attempt to process it before applying.
You can also link to another Pen here, and we'll pull the JavaScript from that Pen and include it. If it's using a matching preprocessor, we'll combine the code before preprocessing, so you can use the linked Pen as a true dependency.
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Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.
<button id="cake">Take Screeny</button>
<br />
<canvas id="fake"></canvas>
const canIRun = navigator.mediaDevices.getDisplayMedia
const takeScreenShot = async () => {
const stream = await navigator.mediaDevices.getDisplayMedia({
video: { mediaSource: 'screen' },
})
// get correct video track
const track = stream.getVideoTracks()[0]
// init Image Capture and not Video stream
const imageCapture = new ImageCapture(track)
// take first frame only
const bitmap = await imageCapture.grabFrame()
// destory video track to prevent more recording / mem leak
track.stop()
const canvas = document.getElementById('fake')
// this could be a document.createElement('canvas') if you want
// draw weird image type to canvas so we can get a useful image
canvas.width = bitmap.width
canvas.height = bitmap.height
const context = canvas.getContext('2d')
context.drawImage(bitmap, 0, 0, bitmap.width, bitmap.height)
const image = canvas.toDataURL()
// this turns the base 64 string to a [File] object
const res = await fetch(image)
const buff = await res.arrayBuffer()
// clone so we can rename, and put into array for easy proccessing
const file = [
new File([buff], `photo_${new Date()}.jpg`, {
type: 'image/jpeg',
}),
]
return file
}
const button = document.getElementById('cake').onclick = () => canIRun ? takeScreenShot() : {}
Also see: Tab Triggers