Cross product of 4D vectors

| i  j  k  l  |   | ay*(bz*cw - cz*bw) - az*(by*cw - cy*bw) + aw*(by*cz - cy*bz) |
| ax ay az aw |   |-ax*(bz*cw - cz*bw) + az*(bx*cw - cx*bw) - aw*(bx*cz - cx*bz) |
| bx by bz bw | = | ax*(by*cw - cy*bw) - ay*(bx*cw - cx*bw) + aw*(bx*cy - cx*by) |
| cx cy cz cw |   |-ax*(by*cz - cy*bz) + ay*(bx*cz - cx*bz) - az*(bx*cy - cx*by) |

/*Your real-number data-type*/
/*typedef float tR;*/
/*typedef tRX4 tR;*/    /*From my previous post on fixed-point data-type*/

/*tR04 is a 4D vector (of ABCD axes); Implementation is trivial*/

static tR04 xMlX(tR04 const&a,tR04 const&b,tR04 const&c)rK{
tR
lbxcy(b.A()*c.B()),lcxby(c.A()*b.B()),lbycz(b.B()*c.C()),lcybz(c.B()*b.C()),
lbzcx(b.C()*c.A()),lczbx(c.C()*b.A()),lbzcw(b.C()*c.D()),lczbw(c.C()*b.D()),
lbwcx(b.D()*c.A()),lcwbx(c.D()*b.A()),lbwcy(b.D()*c.B()),lcwby(c.D()*b.B());
tR
lbxcyNcxby(lbxcy-lcxby),lbyczNcybz(lbycz-lcybz),lbzcxNczbx(lbzcx-lczbx),
lbzcwNczbw(lbzcw-lczbw),lbwcxNcwbx(lbwcx-lcwbx),lbwcyNcwby(lbwcy-lcwby);
return tR04(
a.B()*lbzcwNczbw+a.C()*lbwcyNcwby+a.D()*lbyczNcybz,
a.D()*lbzcxNczbx-a.A()*lbzcwNczbw-a.C()*lbwcxNcwbx,
a.D()*lbxcyNcxby-a.A()*lbwcyNcwby+a.B()*lbwcxNcwbx,
a.B()*lbzcxNczbx-a.A()*lbyczNcybz-a.C()*lbxcyNcxby);}