title: Highlight polygon and tint rest of map using Google Maps
body: <p>I'd like to display a highlighted polygon using Google Maps. The idea is that the polygon in question would be displayed normally and the rest of the map should be darkened a little bit. </p>
  
  <p>So, is this even possible do this with Google Map API's? If yes, with what version (v2, v3)? Would it be easier to do it with other map toolkits, like openlayers?</p>
  
  <p><strong>PS:</strong> One idea I had, was to build an inverse polygon (in this example, the whole world minus the shape of austria) and then display a black colored overlay with transparency using this inverted polygon. But that seems to be quite complicated to me.</p>