| 摘要 |
The system displays linear features on a gray-scale or other multiple-intensity display device with greater apparent smoothness by selecting the intensities of picture elements in the neighbourhood of the feature in dependence on their closest distances to the feature. Straight lines are generated by a vector generator (4) which conducts scans across the line. The closest distance from the picture element currently reached by the scan to the center of the line is held in an accumulator (18), which at each step of the scan is incremented or decremented from a register (20 or 21) holding the change in the distance. Each scan is terminated when a comparator (26) indicates that the intensity has reached that of the background. This scanning technique allows lines of varying width to be displayed easily. The position of the picture element along the line is held in an accumulator 19, used to address a table (22) holding the width at that point. A similar scanning technique is used in a circle generator.
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