Obtaining 'area' information from 'pictslider'

Hi there!

I'm creating simple visuals and game-play mechanics for a darts game as part of my masters degree (focused on audio for interactivity). I'm using a pictslider for the dart board, using the knob as the cross-hair for aiming your dart. So far I've got a system that will add the darts together as you go through each turn, automatically subtract the input scores and switch between the two players at the end of their go.

What I'm currently struggling to do is figure out a way to calculate which number you have hit from the two pictslider outputs.

I've been trying to use 'if' statements to determine if the player is within a certain area of the dartboard but am having trouble defining these areas in the first place. For example I have only been able to make a square area for the bullseye when ideally I'd need a more circular one.

This may just be my lack of understanding of mathematical functions but does anyone know a way that I can define the separate triangular and circular areas of the dart board from the pictslider outputs, or alternatively if there is a better object to use than a pictslider to achieve what I am trying to do?

Thanks!

Liam