Running the line: line drawing using runs and runs of runs

The efficiency of line drawing algorithms underwrites the performance of many rendering and visualisation systems. Therefore to significantly improve the process of line drawing, techniques have been developed to draw the line not pixel by pixel but by using higher order primitives such as runs and run length slices. In this paper we present a line drawing algorithm based on runs of runs, which is the next step in this progression. We will also discuss a number of special cases in the structure of runs and runs of runs within the line that can be used to short circuit the drawing process. These special cases can be used to help counter a common criticism that run-based techniques are less applicable for very short lines. In fact we will argue that the use of higher order primitives provides additional structural information that can be used to accelerate secondary processes within the graphics system, such as within the raster memory management.