public static (XY min, XY max) MinMax(this ReadOnlySpan <XY> points)
{
var min = new XY(float.PositiveInfinity);
var max = new XY(float.NegativeInfinity);
foreach (var p in points)
{
min = XY.Min(min, p);
max = XY.Max(max, p);
}
return(min, max);
}