retina_support_create_images

function retina_support_create_images( $file, $width, $height, $crop = false ) {
    if ( $width || $height ) {
        $resized_file = wp_get_image_editor( $file );
        if ( ! is_wp_error( $resized_file ) ) {
            $filename = $resized_file->generate_filename( $width . 'x' . $height . '@2x' );
 
            $resized_file->resize( $width * 2, $height * 2, $crop );
            $resized_file->save( $filename );
 
            $info = $resized_file->get_size();
 
            return array(
                'file' => wp_basename( $filename ),
                'width' => $info['width'],
                'height' => $info['height'],
            );
        }
    }
    return false;
}