Convert a set of images into a spritesheet and CSS variables via gulp, support @3x.
Support: css, scss, stylus and json.
Based on gulp.spritesmith
npm i gulp.spritesmith.3x
var gulp = require('gulp');
var sprite = require('gulp.spritesmith.3x');
gulp.task('sprite', function() {
  var spriteData = gulp.src('./dist/img/sprite/*.png')
    .pipe(sprite({
      retinaSrcFilter: './dist/img/sprite/*@2x.png',
      retinaImgName: '[email protected]',
      retina3xSrcFilter: './dist/img/sprite/*@3x.png',
      retina3xImgName: '[email protected]',
      imgName: 'sprite.png',
      imgPath: '../img/sprite.png',
      retinaImgPath: '../img/[email protected]',
      retina3xImgPath: '../img/[email protected]',
      cssName: 'sprites.css'
    }));
  spriteData.img.pipe(gulp.dest('./dist/img/'));
  spriteData.css.pipe(gulp.dest('./sass/'));
});.icon-home {
   @include retina-sprite($home-group, $home-group-3x);
}.icon-home
  @include retina-sprite($home-group, $home-group-3x).icon-home {
  .retina-sprite(@home-group, @home-group-3x);
}.icon-home {
  retinaSprite($home_group, $home_group_3x);
}