Applying Rounding-Up Integral Linear Interpolation to the Scan-Conversion of Filled Polygons

This paper is motivated by a special linear interpolation problem encountered in scan-line algorithms for scanconversion of lled polygons. Rounding-up integral linear interpolation is de ned and its e cient computation is discussed. The paper then incorporates rounding-up integral linear interpolation into a scan-line algorithm for lled polygons, and it discusses the implementation of the algorithm. This approach has the advantage of only requiring integer arithmetic in the calculations. Furthermore, the approach provides a uni ed treatment for calculating span extrema for left and right edges of the polygon that guarantees the mutual exclusiveness of the ownership of boundary pixels of two lled polygons sharing an edge.