bp_document_scaled_image_path( $attachment_id )

function bp_document_scaled_image_path( $attachment_id ) {
	$is_image = wp_attachment_is_image( $attachment_id );
	$img_url  = get_attached_file( $attachment_id );
	$meta             = wp_get_attachment_metadata( $attachment_id );
	$img_url_basename = wp_basename( $img_url );
	if ( ! $is_image ) {
		if ( ! empty( $meta['sizes']['full'] ) ) {
			$img_url = str_replace( $img_url_basename, $meta['sizes']['full']['file'], $img_url );
		}
	}

	return $img_url;
}