Compute the cofactor matrix of the upper left 3x3 submatrix of <code>this</code>
and store it into <code>dest</code>.
All other values of <code>dest</code> will be set to {@link #identity() identity}.
<p>
The cofactor matrix can be used instead of {@link #normal(Matrix4d)} to transform normals
when the orientation of the normals with respect to the surface should be preserved.
Compute the cofactor matrix of the upper left 3x3 submatrix of <code>this</code> and store it into <code>dest</code>. All other values of <code>dest</code> will be set to {@link #identity() identity}. <p> The cofactor matrix can be used instead of {@link #normal(Matrix4d)} to transform normals when the orientation of the normals with respect to the surface should be preserved.
@param dest will hold the result @return dest