Cutting edge

Still generalizing bezier shape patching. New algo, by considering :

• a bezier surface defined by a close four-parts bezier curve
• a generalized 2D coord system can be defined on this surface, coord being between 0.0 and 1.0
• algo can then compute a sub surface defined by two "points" of the previous bezier surface

Thus can be defined and computed the image iterated form :

• the bezier surface is defined by a pic bezier, completed to be closed
• four sub-surfaces are computed, from top to bottom