Tiny JSX helper function for high-DPI (Retina Display) images.

394 bytes minified and gzipped for ESM (830 bytes for ES5).

Installation

npm install --save img-srcx
# or
yarn install img-srcx
# or
pnpm install img-srcx

If you’re using this in older runtimes, such as node 8, Internet Explorer, or Android before 4.4.4, you’ll need to use a URL polyfill. You may find Can I use URL? useful.

Example

import { srcx, type Scale } from "img-srcx";

function MyImageComponent({ src, forceScale }: { src: string; forceScale?: Scale; }) {
	return <img {...srcx(src, { forceScale })} />;
}

function Root() {
	return (
		<div>
			<MyImageComponent src="https://repo.chariz.com/CydiaIcon.png" />
			<MyImageComponent src="https://www.google.com/google.jpg" forceScale={1} />
			<MyImageComponent src="https://github.githubassets.com/favicons/favicon.svg" />
		</div>
	);
}

ReactDOM.render(
	<Root />,
	document.getElementById("root")
);

Yields the following rendered HTML:

<div>
	<img
		src="https://repo.chariz.com/CydiaIcon.png"
		srcSet="https://repo.chariz.com/[email protected] 2x,https://repo.chariz.com/[email protected] 3x">

	<img
		src="https://www.google.com/google.jpg">

	<img
		src="https://github.githubassets.com/favicons/favicon.svg">
</div>

Usage

srcx(src: string, options?: { scales?: Scale[], forceScale?: Scale }): { src: string; srcSet?: string }

Returns JSX properties for use on an <img> element. The src and srcSet attributes set as appropriate for the given parameters.

• src: The URL of the image to be displayed. Will be passed through exactly as the src attribute, unless forceScale is set.
• options: Optional object with the following properties:
  • scales: An array of image scales to use. Defaults to [1, 2, 3]. The lowest scale will be used as the src attribute, and the remainder will be used as the srcSet attribute, unless forceScale is set.
  • forceScale: The minimum scale to use. If set, the src attribute will be set to the URL matching the given scale, and the srcSet attribute will be set to the remaining scales above the given scale.

Paths ending in .svg will be returned as-is, without srcSet.

Scale

A type for indicating scale factors. This is defined to 1 | 2 | 3, matching the common scale factors for high-DPI images.

Credits

Developed by Chariz:

• Adam Demasi (@kirb)

License

Licensed under the Apache License, version 2.0. Refer to LICENSE.md.