Envira - Random Image Order

envira-random-image-order.php

<?php
/**
* Plugin Name: Envira Gallery - Random Image Order
* Plugin URI: http://enviragallery.com
* Version: 1.0
* Author: Tim Carr
* Author URI: http://www.n7studios.co.uk
* Description: Display image thumbnails in a random order
*/

/**
* Shuffle gallery images in the data so they are randomly ordered
*
* @param array $data Gallery data
* @param int $galleryID Gallery ID
* @return array Gallery data
*/
function envira_gallery_random_image_order( $data, $galleryID ) {

	// IDs of galleries to randomize
	$galleriesToRandomize = array(
		391,
		392	
	);
	
	// Check if we need to randomize this gallery
	if ( !in_array( $galleryID, $galleriesToRandomize) ) {
		return $data;
	}

	// Shuffle keys
	$keys = array_keys($data['gallery']);
	shuffle($keys);

	// Rebuild array in new order
	$new = array();
    foreach($keys as $key) {
        $new[$key] = $data['gallery'][$key];
    }

	// Assign back to gallery
    $data['gallery'] = $new;

	// Return data
	return $data;	
	
}
add_action( 'envira_gallery_pre_data', 'envira_gallery_random_image_order', 10, 2 );

Tim, I just found this and it is a HUGE help to a project I'm doing. Thank you!