fn restrict_curve_to_fat_line<S: Scalar>(
curve1: &CubicBezierSegment<S>,
curve2: &CubicBezierSegment<S>,
) -> Option<(S, S)>
fn restrict_curve_to_fat_line<S: Scalar>(
curve1: &CubicBezierSegment<S>,
curve2: &CubicBezierSegment<S>,
) -> Option<(S, S)>