  Motivated by applications in architecture and design, we present a novel
method for increasing the developability of a B-spline surface. We use the
property that the Gauss image of a developable surface is 1-dimensional and can
be locally well approximated by circles. This is cast into an algorithm for
thinning the Gauss image by increasing the planarity of the Gauss images of
appropriate neighborhoods. A variation of the main method allows us to tackle
the problem of paneling a freeform architectural surface with developable
panels, in particular enforcing rotational cylindrical, rotational conical and
planar panels, which are the main preferred types of developable panels in
architecture due to the reduced cost of manufacturing.
