more results...

Here's what the graph looks like, with more "realistic" values for the string positions:


Notice that now, *both* of the functions "bend back around".  The radius reaches a minimum somewhere in the middle, and by the bridge end, it has started to go up again, very slightly.  Similarly, the center Y position is at its highest value (i.e., closest to the top surface of the fingerboard) in the same general region of the middle, and it has started to go down at the bridge end.

The new, "more-realistic" values:

/*  position values in mm  */
#define X1_INIT (-22.5)
#define Y1_INIT (-3.0)
#define X1_FINAL (-33.0)
#define Y1_FINAL (-25.0)
#define X2_INIT (-7.5)
#define Y2_INIT (0.0)
#define X2_FINAL (-11.0)
#define Y2_FINAL (0.0)

(And (X3,Y3) is the mirror of (X2,Y2), e.g., (7.5,0) <-> (-7.5,0).)

 I think I need to create a graphical representation of the final shape...


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