With the progress of computers and peripheral devices. the application of computer graphics in teal world is ever-widening. Especially, animation is used widely in the entertainment industry, education, and scientific research. In these areas, scan-line methods have been used widely for fast image generation. A fast scan-line algorithm for a raster-scan graphics display is proposed based on an observation that a sequence of successive image frames in animation mostly consists of still objects with relatively few moving objects. In the proposed algorithm, successive images are generated using the background image composed of still objects only, and moving image composed only of moving objects. The color of each pixel in the successive images is then determined by one, which is nearer from eye, from the two candidate pixels, where one is from the background image and the other is from the moving image. The background image is generated once in the whole process, while the moving image is generated using an interpolation of two images generated at the start and end time of the given time interval whenever the successive images are generated. For the purpose of fast shadow generation, the shadows are classified into three groups, i.e., basic shadows generated by still objects on the still objects, still shadows generated by still objects on the moving objects, and moving shadows generated by moving objects on both still objects and moving objects. These shadow can be generated very quickly by utilizing the frame coherence. According to the experimental results, a speed up factor of 3.2 to 12.8, depending on the percentage of the moving objects among all objects, was obtained using our algorithm, compared to the conventional scheme not utilizing the frame-to-frame image coherence.
Ray tracing has been used for generating quality images in various applications. A problem with ray tracing is its computing time, which becomes more severe when one wants to create a seq...