CLIPEDGE Clip an edge with a rectangular box.

   EDGE2 = clipEdge(EDGE, BOX);
   EDGE: [x1 y1 x2 y2],
   BOX : [xmin xmax ymin ymax], or [xmin xmax ; ymin ymax].
   return :
   EDGE2 = [xc1 yc1 xc2 yc2];

   If clipping is null, return [0 0 0 0];

   if EDGE is a N-by-4 array, return an N-by-4 array, corresponding to
   each clipped edge.

   See also
   edges2d, boxes2d, clipLine

Package: matgeom