image-resolution-loader

The image-resolution-loader takes your image and returns @1x, @2x and @3x resolution versions of it.

Install

To begin, you'll need to install image-resolution-loader:

$ npm install image-resolution-loader --save-dev

or

$ yarn add image-resolution-loader -D

Usage

Add loader to your webpack config:

webpack.config.js

module.exports = {
  module: {
    rules: [
      {
        test: /\.(png|jpe?g|webp)$/i,
        use: [
          {
            loader: 'image-resolution-loader',
            options: {
              // loader options, see below
            },
          },
        ],
      },
    ],
  },
}

Then import (or require) the target file(s) in one of the bundle's files:

file.js

import images from ('./file.png')

or

const images = require('./file.png')

And run webpack via your preferred method. The Loader will accept your image as the initial with 3x resolution and will generate from it 2x and 1x versions. Next, it will emit these images on the specified path and return the object, which will contain the path to the all versions of the image and srcSet.

ℹ️ It is recommended to set the height and width of the initial image multiple of 3

Options

name

Type: String|Function Default: '[name][resolution].[ext]'

Specifies a custom filename template for the target file(s) using the query parameter name. For example, to emit a file from your context directory into the output directory retaining the full directory structure, you might use:

ℹ️ By default the path and name you specify will output the file in that same directory, and will also use the same URI path to access the file.

outputPath

Type: String|Function Default: undefined

Specify a filesystem path where the target file(s) will be placed.

publicPath

Type: String|Function Default: __webpack_public_path__

Specifies a custom public path for the target file(s).

webp

Type: object Default: {}

sharp is used for optimizing webp images.The default options of sharp.webp() are used if you omit this option.

jpg

Type: object Default: {}

sharp is used for optimizing jpg images.The default options of sharp.jpg() are used if you omit this option.

png

Type: object Default: {}

imagemin-pngquant is used for optimizing png images.The default options of pngquant are used if you omit this option.

zopfli

Type: object Default: {}

imagemin-zopfli is used for compressing png images.The default options of imagemin-zopfli are used if you omit this option.

disable

Type: Boolean Default: false

Disable processing of images by this loader (useful in development). Images data will still be generated but only for the original resolution.

Placeholders

Full information about placeholders you can find here.

[resolution]

Type: String Default: @1x | @2x | @3x

Image resolution.

Examples

file.js

import images from './file.png'

webpack.config.js

module.exports = {
  module: {
    rules: [
      {
        test: /\.(png|jpe?g|webp)$/i,
        use: [
          {
            loader: 'image-resolution-loader',
          },
        ],
      },
    ],
  },
}

The result will be a variable images, containing the following information:

{
  '1x': '/file@1x.png',
  '2x': '/file@2x.png',
  '3x': '/file@3x.png',
  images: [{
    path: '/file@1x.png',
    width: /* width of 1x image */,
    height: /* height of 1x image */,
    resolution: '1x',
  }, {
    path: '/file@2x.png',
    width: /* width of 2x image */,
    height: /* height of 2x image */,
    resolution: '2x',
  }, {
    path: '/file@1x.png',
    width: /* width of 3x image */,
    height: /* height of 3x image */,
    resolution: '3x',
  }],
  imagesByResolution: {
    '1x': {
      path: '/file@1x.png',
      width: /* width of 1x image */,
      height: /* height of 1x image */,
    },
    '2x': {
      path: '/file@2x.png',
      width: /* width of 2x image */,
      height: /* height of 2x image */,
    },
    '3x': {
      path: '/file@3x.png',
      width: /* width of 3x image */,
      height: /* height of 3x image */,
    },
    srcSet: '/file@1x.png 1x,/file@2x.png 2x,/file@3x.png 3x',
  },

License

MIT