What am I trying to ask?

What am I trying to ask?

I will apologize in advance if this appears vague. The problem I am having
is that I am not certain how to properly articulate what I want to achieve
into the correct question. I will try to describe my goal.
This is for a windows 8 tablet app. Imagine a set of rectangles across the
top of the screen, much like piano keys. The user will drag a key down a
little (I can do this). Then touching the top end of the rectangle they
will drag their finger in a circle around it, as they do so the rectangle
will fan out into an actual circle. Then when finished they would drag the
top around the opposite way closing it. Sort of like one of those Japanese
hand fans.
What do I search for or how do I phrase this in such a way that will point
me in the right direction.
Thanks in advance, its maddening not being able figure out what I need
search for.