Compute the cofactor matrix of the upper left 3x3 submatrix of <code>this</code>.
<p>
The cofactor matrix can be used instead of {@link #normal()} 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>. <p> The cofactor matrix can be used instead of {@link #normal()} to transform normals when the orientation of the normals with respect to the surface should be preserved.
@return this