@article{Brassel:1979:ASR,
number = {3},
month = aug,
author = {Kurt E. Brassel and Robin Fegeas},
optkey = {},
series = CGPACS,
localfile = {papers/Brassel.1979.ASR.pdf},
address = {New York},
publisher = {ACM Press},
doi = {http://doi.acm.org/10.1145/800249.807434},
organization = {ACM SIGGRAPH},
journal = SIGGRAPH79,
volume = {13},
optstatus = {URL},
title = {{A}n {A}lgorithm for {S}hading of {R}egions on {V}ector {D}isplay
{D}evices},
abstract = { The display of shaded polygons by line, cross-hatch, and dot
patterns on vector devices is a task frequently used in computer
graphics and computer cartography. In applications such as the
production of shaded maps polygon shading turns out to be critical
with respect to time requirements, and the development of
efficient algorithms is of importance. Given an arbitrary polygon
in the plane without self-crossing edges (simply-connected
polygon), the task at hand is to shade this polygon with one or
two sets of parallel lines where for each set a shading angle and
a line distance are given. The basic concept of this new algorithm
is to decompose the polygon into a set of mutually exclusive
trapezoids (in special cases triangles) where the parallel edges
of the trapezoids are parallel to the desired shading lines. These
trapezoids and triangles are then shaded in a fast procedure. In
its present form the algorithm handles regions with up to 300
islands. Possible extensions include the construction of dash and
cross patterns.},
year = {1979},
pages = {126--133},
}
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