1. A method of scanning using a charged particle beam, comprising: (a) directing a charged particle beam toward a workpiece in an initial scan pattern within a field of view while detecting secondary particles emanating from the workpiece surface in response to impact of the charged particle beam, the secondary particles corresponding to a property of the workpiece; (b) determining a point along the initial scan pattern at which a property of the workpiece changes to identify a point on an edge of a feature in the workpiece; (c) directing the charged particle beam in a localized scan pattern, the starting point of the subsequent localized scan pattern being determined by the point identified on the edge of the feature, the subsequent localized scan pattern intersecting the edge of the feature at one or more intersection point as determined by a change in the property of the workpiece at the edge; and (d) directing the charged particle beam in a plurality of subsequent localized scan patterns, with the starting point of the subsequent localized scan patterns being determined based on the intersection points of one or more previous localized scan patterns with the edge of the feature in order to determine multiple points of the edge of the feature to trace an outline of the feature.