Customised single product page

Hi,
I’ve created a product which has 2 custom attributes, a latitude and a longitude.
Now I would like to create a custom single product page which has a Google Map on it. The user creates a marker at a location.
All of the above I can easily do and I am pretty good with PHP and JS.

Now the bit I can’t figure out, is the interaction with WooCommerce.
So, I can display the price on the page and I can display the “Add Cart” button ([add_to_cart id=”99″]) using a shortcode, but how do I add my order to the cart and include the coordinates as the custom attributes for the ordering system.

If I was using a REST API I might do:
http://mysite.com/addtocart.php?productid=99,latitude=x,logitude=y

Not the best example, but I hope you get the idea.

Hopefully that makes some sort of sense.

http://wordpress.org/extend/plugins/woocommerce/