Function b2RayCastSegment 

pub unsafe extern "C" fn b2RayCastSegment(
    input: *const b2RayCastInput,
    shape: *const b2Segment,
    oneSided: bool,
) -> b2CastOutput

Ray cast versus segment in shape local space. Optionally treat the segment as one-sided with hits from the left side being treated as a miss.