Here is my code that performs the cross product. I hope it helps.

/*$Func************************************************************************

$$Synopsis TPoint TPoint::operator* (const TPoint& tp) const

tp Ref to the operation''s right operand.

$$Returns Returns a TPoint which is the result of the operation.

$$Description TPoint-TPoint cross product operator.

| a , b , c |
(Rx, Ry, Rz) => | x1, y1, z1 |
| x2, y2, z2 |

(Rx, Ry, Rz) => ((y1*z2 - y2*z1), -(x1*z2 - x2*z1), (x1*y2 - x2*y1))

$$Remarks This operator is not inversable, i.e. A X B != B X A.

$$Pre-Conditions None.

$$Post-Conditions None.

$$Exceptions None.

$$See Also None.

******X******************X*******************X*******************X**********$*/
TPoint TPoint::operator* ( const TPoint& tp ) const
{
TPoint result;

result.x = ( y * tp.z - tp.y * z );
result.y = ( tp.x * z - x * tp.z );
result.z = ( x * tp.y - tp.x * y );

return result;
}