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    Experience with a Difference Engine for Graphics
    (The Eurographics Association, 1994) Kuijk, A.A.M.; Blake, E.H.; Steffens, E.H.; W. Strasser
    "The prototype of a novel raster graphics architecture has now become operational. The display hardware can be regarded as a very fast difference engine that works in two-dimensions. The speed is partly achieved by the use of custom VLSI components for the lowest level primitive operations and this permits the video rate reconstruction of images and other signals com pressed by encoding them on various polynomial bases. A novel feature of the architecture is that it avoids the use of a frame buffer. The paper describes our experience with the new hardware in terms of positive and negative performance aspects. We discuss the architecture and its operating parameters. Another part of the paper evaluates our ex perience of hardware development in an academic set ting. We believe there are significant lessons here for graphics researchers who might want to develop their own systems."
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    The Mesh Propagation Algorithm for Isosurface Construction
    (Blackwell Science Ltd and the Eurographics Association, 1994) Howic, C.T.; Blake, E.H.
    A new algorithm, Mesh Propagation, is presented for the generation of isosurfaces from three-dimensional discrete data sets. While producing the same surface mesh as that generated by a corrected Marching Cubes algorithm, its characteristic is that it constructs an isosurface using connected strips of dynamically triangulated polygons. This compact data structure speeds up surface construction and reduces surface storage requirements. The surface can also be displayed more quickly, particularly where there is hardware support for rendering triangle strips.With engineering as well as medical imaging applications in mind, the algorithm can be used with both irregular and rectilinear grids of data, the primitive volume elements need not be hexahedral only, and volumes of heterogeneous polyhedral elements are supported without traversal complications.The algorithm propagates through the cells in the grid and uses the same lookup table topologies as Marching Cubes to determine patches of surface-element intersection- additional tables are used for non-hexahedral elements. The surface patches are dynamically coded into triangle strips which are then concatenated and linked to construct the surface. The data structures used for propagating through the volume overcome the topological ambiguities associated with table-based methods of surface construction and no holes are generated in the final mesh.