How do I make this blend mode?

Hi,

I have a game with objects in the background and a black sprite that is in front.

I want a 100x100 white sprite that blends with the black sprite and when those 2 overlap the game objects in the background to become visible.

Like this:http://forums.flixel.org/index.php?topic=6552.0

How can I do that?

I tried with blend mode multiply no effect.

Thanks

If I understand correctly, you want the game to be darker but have spots where there is light? (something like this?)

Click "New project" and pick from one of the examples that teach about blending modes. There's one called Destination Out that can achieve that

Yes this is the effect I want to achieve but the destination out doesn't help.

You have to put it all ('darkness' and 'light' sprites) all on their own layer, and set the layer's property "Set own texture" to "Yes"

Now is working. Thanks