Hierarchical schemes for curve representation

The performance of three curve representation schemes are compared. They are the strip-tree, Bezier-curve-employing, and arc-tree methods. Each scheme represents a curved shape as a hierarchy of approximations, where higher levels in the hierarchy correspond to coarser approximations of the curve. In addition, each approximation typically corresponds to a bounding area that encloses the actual curve. When geometric operations are computed, coarse approximation of the curve are initially addressed and finer approximation levels are processed if necessary. It is shown that the three representations differ in the choice of bounding areas, the type and amount of information stored at each approximation level, and the method of deciding whether to proceed to finer approximations.<>