@article{Weiler:1977:HSR,
  optcitations = {Appel:1967:TNQ, },
  number = {3},
  month = jul,
  author = {Kevin Weiler and Peter Atherton},
  optkey = {},
  series = CGPACS,
  localfile = {papers/Weiler.1977.HSR.pdf},
  address = {New York},
  publisher = {ACM Press},
  doi = {http://doi.acm.org/10.1145/563858.563896},
  organization = {ACM SIGGRAPH},
  journal = SIGGRAPH77,
  volume = {11},
  title = {{H}idden {S}urface {R}emoval {U}sing {P}olygon {A}rea {S}orting},
  abstract = {A polygon hidden surface and hidden line removal algorithm is
              presented. The algorithm recursively subdivides the image into
              polygon shaped windows until the depth order within the window is
              found. Accuracy of the input data is preserved. The approach is
              based on a two-dimensional polygon clipper which is sufficiently
              general to clip a concave polygon with holes to the borders of a
              concave polygon with holes. A major advantage of the algorithm is
              that the polygon form of the output is the same as the polygon
              form of the input. This allows entering previously calculated
              images to the system for further processing. Shadow casting may
              then be performed by first producing a hidden surface removed view
              from the vantage point of the light source and then resubmitting
              these tagged polygons for hidden surface removal from the position
              of the observer. Planar surface detail also becomes easy to
              represent without increasing the complexity of the hidden surface
              problem. Translucency is also possible. Calculation times are
              primarily related to the visible complexity of the final image,
              but can range from a linear to an exponential relationship with
              the number of input polygons depending on the particular
              environment portrayed. To avoid excessive computation time, the
              implementation uses a screen area subdivision preprocessor to
              create several windows, each containing a specified number of
              polygons. The hidden surface algorithm is applied to each of these
              windows separately. This technique avoids the difficulties of
              subdividing by screen area down to the screen resolution level
              while maintaining the advantages of the polygon area sort
              method.},
  year = {1977},
  pages = {214--222},
}