Gulp angular yo

// https://github.com/twolfson/gulp.spritesmith
// Example task with retina setup:
// @1x and @2x should have exact proportions
// otherwise spritesmith throws:
// Error: Normal sprite has inconsistent size with retina sprite.
// details and workaround: https://github.com/twolfson/gulp.spritesmith/issues/57

var spritesmith = require('gulp.spritesmith');
var buffer = require('vinyl-buffer');
var imagemin = require('gulp-imagemin');
var del = require('del');
var merge = require('merge-stream');

gulp.task('sprites', function () {
  return del([
    path.join('path_to_compiled/sprite.png'),
    path.join('path_to_compiled/sprite.less')
  ])
    .then(function () {
      var spriteData = gulp.src('path_to_source/*.png')
        .pipe(spritesmith({
          retinaSrcFilter: ['path_to_source/*@2x.png'],
          imgName: 'sprite.png',
          retinaImgName: 'sprite@2x.png',
          cssName: 'sprite.less',
          imgPath: 'path_to_use_in_css/sprite.png'
        }));

      var imgStream = spriteData.img
        .pipe(buffer())
        .pipe(imagemin())
        .pipe('path_to_source_image_folder');

      var cssStream = spriteData.css
        .pipe('path_to_source_less_folder');

      return merge(imgStream, cssStream);
    });
});