sin( 0.08 ) = 0.001396263. Therefore, to get an arc one pixel wide at the widest point, ,the circle would need to be 1/ 0.001396263 = 716.1974766 pixels radius, call it 716 pixels.

Any arc smaller would be indistinguishable from a straight line, frfom the center to the point on the cicumference .... if you are only drawing the arc, you would have a point for arc less that 0.08 degrees, when you switch to an arc of two points.

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