addMediaGalleryAttributeToCollection

gistfile1.php

// Source: http://www.magentocommerce.com/boards/viewthread/17414/#t141830

function addMediaGalleryAttributeToCollection(Mage_Catalog_Model_Resource_Eav_Mysql4_Product_Collection $_productCollection) {
    $_mediaGalleryAttributeId = Mage::getSingleton('eav/config')->getAttribute('catalog_product', 'media_gallery')->getAttributeId();
    $_read = Mage::getSingleton('core/resource')->getConnection('catalog_read');
    
    $_mediaGalleryData = $_read->fetchAll('
        SELECT
            main.entity_id, `main`.`value_id`, `main`.`value` AS `file`,
            `value`.`label`, `value`.`position`, `value`.`disabled`, `default_value`.`label` AS `label_default`,
            `default_value`.`position` AS `position_default`,
            `default_value`.`disabled` AS `disabled_default`
        FROM `catalog_product_entity_media_gallery` AS `main`
            LEFT JOIN `catalog_product_entity_media_gallery_value` AS `value`
                ON main.value_id=value.value_id AND value.store_id=' . Mage::app()->getStore()->getId() . '
            LEFT JOIN `catalog_product_entity_media_gallery_value` AS `default_value`
                ON main.value_id=default_value.value_id AND default_value.store_id=0
        WHERE (
            main.attribute_id = ' . $_read->quote($_mediaGalleryAttributeId) . ') 
            AND (main.entity_id IN (' . $_read->quote($_productCollection->getAllIds()) . '))
        ORDER BY IF(value.position IS NULL, default_value.position, value.position) ASC    
    ');
    
    $_mediaGalleryByProductId = array();
    foreach ($_mediaGalleryData as $_galleryImage) {
        $k = $_galleryImage['entity_id'];
        unset($_galleryImage['entity_id']);
        if (!isset($_mediaGalleryByProductId[$k])) {
            $_mediaGalleryByProductId[$k] = array();
        }
        $_mediaGalleryByProductId[$k][] = $_galleryImage;
    }
    unset($_mediaGalleryData);
    foreach ($_productCollection as &$_product) {
        $_productId = $_product->getData('entity_id');
        if (isset($_mediaGalleryByProductId[$_productId])) {
            $_product->setData('media_gallery', array('images' => $_mediaGalleryByProductId[$_productId]));
        }
    }
    unset($_mediaGalleryByProductId);
    
    return $_productCollection;
}