Anti-aliased line drawing using brush extrusion

Abstract

This algorithm draws lines on a gray-scale raster display by dragging a "brush" along the path of the line. The style of the line is determined by the properties of the brush. An anti-aliasing calculation is performed once for the brush itself and thereafter only a trivial additional operation is needed for each pixel through which the brush is dragged to yield an anti-aliased line.There are few constraints on the size, shape, and attributes of the brush. Lines can be curved as well as straight, It is possible to produce lines with a three dimensional appearance.

Style Conversion of Cartoon Animation

“…The heart of our method is a new mechanism to place strokes depicting outlines of moving characters. In literature many brush models have been proposed [9,10] to produce a variety of strokes in terms of shape, texture and placement of the brush. Strassmann [11] modeled the ink-laying process of bristle brush on paper.…”

Antialiasing of curves by discrete pre-filtering

“…The Quantel Paintbox painting system developed somewhat later uses a similar technique in which hand-drawn curves are painted as overlapping imprints of sub-pixel positioned cylindrical brushes convolved with an apparently ad hoc filter [34]. Whitted strokes curves with a brush of arbitrary footprint and intensity profile, using a Z-buffer technique to overwrite only those pixels where current position of the brush indexes a greater intensity than in previous writes [36]. In our approach however, we do not approximate the curve by a series of overlapping blobs or a series of straight line segments but sample the convolved ideal image by an approximate method whose accuracy is controllable both spatially and in terms of intensity [7,8,12,13].…”

Hardware antialiasing of lines and polygons

“…1). One solution to these overlapping effects is to solve the hidden surface problem for finite width lines [28]. Alternatively lines can be modeled as infinitely thin, so that the antialiasing filter itself gives thickness to the line and "shape" to the endpoints.…”