A method and apparatus for visiting all productive stamp positions for a two-dimensional convex polygonal object. The object is visited with a stamp that has a stamp rectangle, and one or more discrete sample points. A productive location is one for which the object contains at least one of the stamp's sample points when the stamp is placed at that location. An unproductive location is one for which the object contains none of the stamp's sample points when the stamp is placed at that location. Stamp locations are discrete points that are separated vertically by the stamp rectangle's height, and horizontally by the stamp rectangle's width. The stamp may move to a nearby position, or to a previously saved position, as it traverses the object. The stamp moves in such a way as to visit all productive locations for an object while avoiding most of the unproductive locations.