typedef __m128 Context;


struct A { float k[2]; };
struct B { float q[4]; };

struct FTransform : thrust::unary_function<A, B>
{
    Context context;
    FTransform(Context context) : context(context) {}
    __attribute__((device)) B operator()(const A& a) const
    {
        B b{{a.k[0], a.k[1], a.k[0]*context.n[0], a.k[1]*context.n[1]}};
        return b;
    }
};