gulpfile.js

var path = require('path')
var gulp = require('gulp')
var webpack = require('gulp-webpack')
var rename = require('gulp-rename')

gulp.task('webpack', function () {
  var sourceFiles = path.resolve(__dirname, 'src')
  var input = path.resolve(sourceFiles, 'pixi-svg-graphics.js')

  return gulp.src(input)
    .pipe(webpack({
      context: sourceFiles,
      output: {
        library: 'SVGGraphics',
        libraryTarget: 'umd',
        filename: 'pixi-svg-graphics.js',
        path: path.resolve(__dirname, 'dist')
      },
      resolve: {
        extensions: ['', '.js'],
        root: sourceFiles
      },
      externals: {
        'pixi.js': {
          root: 'PIXI',
          commonjs: 'pixi.js',
          commonjs2: 'pixi.js',
          amd: 'pixi.js'
        }
      }
    }))
    .pipe(gulp.dest(path.resolve(__dirname, 'dist')))
})

gulp.task('watch', function() {
  gulp.watch('src/pixi-svg-graphics.js', gulp.series(['webpack']))
})

gulp.task('default', gulp.series(['webpack']))