| 摘要 |
A procedure is embodied as program code on a medium that is readable by a computer. The program code is used to direct operation of the computer to render lines corresponding to samples, from a digitizer tablet, that map onto a same pixel of a display screen. The program code includes a code segment for subdividing a display screen pixel into a plurality of sub-pixels; a code segment, responsive to each sample that maps onto a current pixel, for mapping the sample onto a sub-pixel center; a code segment for computing a bounding box that is centered on the sample; a code segment, responsive to a size and position of the bounding box, for determining those pixels in a neighborhood of the current pixel that are overlapped by the bounding box; and a code segment for varying an intensity of the overlapped pixels according to the amount of overlap. The code segment that determines pixels in a neighborhood of the current pixel preferably operates to store overlap-related information, for all of the samples that map onto the current pixel, within an auxiliary array. The code segment that varies the intensity then uses the contents of the auxiliary array to vary the intensity of corresponding pixel locations in a frame buffer that has an output coupled to the display screen. The code segment that varies the intensity is responsive to a sub-pixel location of the sample, and to a precomputed summed area table (SAT), for determining an amount by which to vary the intensity.
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