TranslationSweep and RotationSweep are used to create polylist objects which are the translational sweep (surface of extrusion) or rotational sweep (surface of rotation) of the Geom g, which must be a vect.
TranslationSweep takes as its arguements the length and direction of the sweep. The returned off object will be a representation of the Geom g swept length units in the direction of the vector p.
RotationSweep forms a surface by rotating the object g by angle units. The angle parameter should be specified in radians. The rotation is about the axis specified by the endpoint end and in the direction axis. The surface of rotation will be divided radially into divisions parts.
If angle is within .01 of 2.0 * pi (as defined in math.h), it will be assumed that a full rotation is desired. In the returned polylist object, the ends of the sweep will refer to the same points to prevent a crack from appearing due to round off error.
Either routine will print out an error message and return NULL if the Geom g is non-NULL and is not of the vect type. Either routine will return NULL (with no error message) if g is NULL.
Celeste Fowler email: fowler@geom.umn.edu The Geometry Center phone: (612) 626-8304 1300 South Second Street Minneapolis, MN 55454