Issue No.06 - November-December (1997 vol.17)
DOI Bookmark: http://doi.ieeecomputersociety.org/10.1109/38.626971
In computerized 2.5D illustration systems, users construct pictures by layering bounded geometrical shapes and specifying graphical properties such as line width, fill color, and transparency. Unfortunately, these graphical properties can only be applied to entire shapes; visual effects that cross apparent shape boundaries require extra shapes or boundaries. This article describes the use of spatially-bounded visual filters, called Magic Lens filters, as components of an illustration. A Magic Lens filter changes the appearance of shapes seen through its interior, making the spatial extent of the effect independent of those shapes' boundaries. Overlapping lenses composes their effects, allowing the designer to easily create visually complex results. Magic Lens filters create a wide range of spatially-bounded visual effects, including the appearance of tinted glass, optical lenses, water, glow, weaving, shadows, x-rays, plaids, and 3D depth, and do so more easily than conventional techniques. This article describes their implementation and shows many examples of illustrations enhanced by Magic Lens filters.
Maureen Stone, Ken Pier, "Enhanced Illustration Using Magic Lens Filters", IEEE Computer Graphics and Applications, vol.17, no. 6, pp. 62-70, November-December 1997, doi:10.1109/38.626971