How to create a ring slider in pixelsense sdk 2.0 that will support touch
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Those questions are relevant to pixelsense device sdk 2.0 (presentation application).

I want to create a slider element in surface that looks like a ring. The user can slide his finger on that ring and stop on any degree between 0 to 360. 

The following link contains an image of the required element. Sliding the element to 90 degrees will look like the left element in the provided link.

[Link to a sample image](http://i.stack.imgur.com/pebJJ.jpg)

**Question 1**  
How to make the element mask in a way that when the user slide on that ring, the element shows only relevant part? 

In the illustration below if the element is currently at 60 degrees and the user starts to slide his finger all the way to 360 then the animation/manipulation should follow his finger and draw the ring until he pauses at 360.

![Illustration of the required slider element][1]

**Question 2**  
Is it possible to perform path gradient that will according to the ring currently shown. The starting point will be opacity 20% and the end point should be opacity 90%. I know that wpf currently doesn't support path gardient but maybe someone know how to bypass that limitation.

Thanks!  
Eran. 