Function ncollide_utils::tetrahedron_signed_volume

pub fn tetrahedron_signed_volume<P: Point>(
    p1: &P, 
    p2: &P, 
    p3: &P, 
    p4: &P
) -> P::Real

Computes the signed volume of a tetrahedron.

If it is positive, p4 is on the half-space pointed by the normal of the oriented triangle (p1, p2, p3).