[PD] Circular scrolling in pd

[James Dunn]

Hi,

I'm trying to implement circular scrolling with the trackpad in pd and 
am approaching it by dividing a circle into segments and trying to 
detect when the mouses moves from one segment to the other. At the 
moment I can only detect 4 segments (basically just the zero crossings) 
which is not really accurate enough.

How would I go about detecting the boundaries of the 12 segments in the 
attached patch (circscroll.pd)?

Eventually I want to detect speed and direction too - but perhaps there 
is a better approach?

any advice welcome.

thanks,

james
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