alpha masking sprites

[rylgh]

Hey,

I'd like to mask off part of sprites with the contents of another sprite.

So for example I've got this sprite and I'd like to mask it with this one
so that this is the result

Is this possible, and if so how would I go about it? I'm not experienced with shaders so I may be missing an obvious method.
Thanks!

[unikronsoftware]

There is a shader posted here which should do the job.
http://2dtoolkit.com/forum/index.php/topic,1700.0.html