The algorithm used to move monitors to the nearest one in "position dialog" is explained here.
Segment equation is used. Let's explain segment equation in order to understand the proccess:
If you have two points, p0, p1 ∈ ℝ 2, the equation of straigh line between p0 and p1 is:
r = v · t + p0where v = p1 - p0, and t ∈ [0,1].
Algorithm calculates equation of the segment between monitor centers. Then, it gets intersection points with edges of monitors:
If v = c1 - c0, c0 and c1 are monitors centers, the equation between them is r = v · t + c0.
where t1 is the parameter of the mentioned equation to get the intersection point with the c1 monitor.
where t2 the parameter with the c0 monitor.
t1, t2 ∈ [0,1].
If t2<t1, the monitors are separated, otherwise the monitors are overlapped.
With the previous information we get:
r1 = v· t1 + c0
r2 = v· t2 + c0
Iff t2<t1, c0 monitor must be moved, and its displacement is provided by r = r1-r2