Function ncollide2d::query::algorithms::gjk::directional_distance

pub fn directional_distance<N, G1: ?Sized, G2: ?Sized>(
    m1: &Isometry<N>, 
    g1: &G1, 
    m2: &Isometry<N>, 
    g2: &G2, 
    dir: &Vector<N>, 
    simplex: &mut VoronoiSimplex<N>
) -> Option<(N, Vector<N>, Point<N>, Point<N>)> where
    N: RealField,
    G1: SupportMap<N>,
    G2: SupportMap<N>, 

Compute the normal and the distance that can travel g1 along the direction dir so that g1 and g2 just touch.