gmap views location

Hi!

My mission is to create a map that is easy to filter, such as http://www.gimmie.se/search/sverige. If you drag the sliders around, you can see that the markers appears/disappears instantly.

This site uses Drupal, Gmap and Views to create the map. I've also accomplished that, but I want to be able to filter my markers just as easy. I believe the way to go is a Javascript that checks every marker in the map object for values, and then hides/shows the marker if the value matches the filter.

I have a test site with gmap/location/views combo. Everything is working great now. The view filters the nodes based on an event date (think of it as a map of today's bake sales). The one thing I don't like is that if there are no bake sales today, it doesn't even render an empty map. I wonder if it would be possible somehow to draw an empty map or maybe otherwise write a message to the page?