Gallery2 Integration

There are a few ways to do this. Here is one technique that I have tried based on an example here http://gallery.menalto.com/files/sample_embedding_wrapper.zip

with this method you can just get the data object from a gallery request by collecting the 'themeData' value (i.e. no html layout - so you can do what you want with the data).

<?php
$data =	runGallery();
var_dump($data['themeData']);


function runGallery()
{

	require_once('/dev/bin/Apache2/htdocs/gallery2/embed.php');
	
	$data = array();
	
	// if anonymous	user, set g2 activeUser	to ''
	$uid = '';

	$init =	GalleryEmbed::init(array(
					'activeUserId' => $uid , 
					'embedUri' => G2EmbedDiscoveryUtilities::normalizeEmbedUri('/gallerymain.php'),
					'g2Uri'	=> G2EmbedDiscoveryUtilities::normalizeG2Uri('/gallery2/') 
					));

	$g2moddata = GalleryEmbed::handleRequest();
	
	if(!isset($g2moddata['isDone'])) 
	{
		$data['bodyHtml'] ='isDone is not defined,something very bad must have happened.';
		return $data;
	}
	
	// exit	if it was an immediate view / request (G2 already outputted	some data)
	if($g2moddata['isDone']) 
	{
		exit; 
	}
	
	
	$data['themeData'] = isset($g2moddata['themeData'])	? $g2moddata['themeData'] :	'';
	
	return $data;
}
?>

WARNING: this is actually totally raw and untested code that I have knocked together quickly - it may not work off the bat - but it is just to give an idea how to intercept data before it is rendered by the gallery template.

There is also the full embed method that get you access to the core API - and then you don't need to start editing G2 code (which I advise against - hacking the code may give quick results but could prove to be a nightmare to maintain).

do full embed like this . . .

$init =	GalleryEmbed::init(array(
                                        'fullInit' => true ,
					'activeUserId' => $uid , 
					'embedUri' => G2EmbedDiscoveryUtilities::normalizeEmbedUri('/gallerymain.php'),
					'g2Uri'	=> G2EmbedDiscoveryUtilities::normalizeG2Uri('/gallery2/') 
					));

Now you can make calls to Core API typically like this

list ($ret, $item) = GalleryCoreApi::loadEntitiesById(7);
if($ret)
{
    echo $ret->html(); // print an error if there was one
    exit;
}
var_dump($item); // print a dump of what we just got

when doing the full embed you don't need to bother with GalleryEmbed::handleRequest().
Hope this helps a bit.
The 2 main docs on this subject are
http://codex.gallery2.org/Gallery2:Embedding:Integration
http://codex.gallery2.org/Gallery2:Embedding