Abstract
A simple rendering method for penumbrae caused by sunlight is proposed to create more realistic outdoor scenery. Only four points are used to define the penumbra area cast by a contour edge so that little storage is needed for penumbra areas. Complex penumbrae caused by such objects as curtains can be rendered. Calculation of illumination in the shadows cast by natural objects, such as trees, mapped on a transparent virtual plane is available. In order to show the usefulness of the proposed method, some computer-generated images with penumbrae are compared with those without penumbrae.
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Takita, S., Kaneda, K., Akinobu, T. et al. A simple method for rendering penumbrae caused by sunlight. The Visual Computer 7, 259–268 (1991). https://doi.org/10.1007/BF01905691
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DOI: https://doi.org/10.1007/BF01905691