custom gallery shortcode for WordPress

custom-gallery-shortcode.php

function parse_gallery_shortcode($atts) {
  global $post;
 	$output = apply_filters('post_gallery','', $atts);
	extract(shortcode_atts(array(
		'orderby' => 'menu_order ASC, ID ASC',
		'id' => $post->ID,
		'itemtag' => 'dl',
		'icontag' => 'dt',
		'captiontag' => 'dd',
		'columns' => 10,
		'size' => 'property-thumb',
		'link' => 'file',
		'ids' => array()
	), $atts));
 
	$args = array(
		'post_type' => 'attachment',
		'posts_per_page' => 10,
		'orderby' => $orderby
		); 
	$images = get_posts($args);
 	
	echo '<div id="gallery-1" class="custom-gallery">';
	foreach ( $images as $image ) {   
		$caption = $image->post_excerpt;
		$description = $image->post_content;
		$title = $image->post_title;
		$pname = $image->post_name;
		$large_img = post_permalink() . $pname . '/';
		if($description == '') $description = $title;
			$image_alt = get_post_meta($image->ID,'_wp_attachment_image_alt', true);
			$img = wp_get_attachment_image_src($image->ID, $size);
		// render gallery here

		echo '<dl class="gallery-item">';
		echo '<dt class="gallery-icon">';
		echo '<a title="' . $title . '" href="' . $large_img . '"><img src="' . $img[0] . '" width="' . $img[1] . '" height="' . $img[2] . '"></a>';
		echo '</dt>';
		echo '</dl>';
		
	}
	echo '</div>';
	
	
}