Things start getting tricky with ArcSegment. An arc is just a partial circumference of an ellipse, but because the ArcSegment must fit in with the paradigm of start points and end points, the arc must be specified with two points on the circumference of some ellipse. But if you define an ellipse with a particular center and radii, how do you specify a point on that ellipse circumference exactly without doing some trigonometry?
The solution is to define only the size of this ellipse and not where the ellipse is positioned. The actual location of the ellipse is defined by the two points.
I think we need an example. Here’s a little line that begins at the point (120, 240) and ends at the point (360, 240).
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