Line patterning apparatus for use with a vector generator comprises a memory storing a plurality of addressable line pattern bit strings. Each string comprises a series of ones and zeros defining a predetermined pattern of dots and/or dashes. Associated with each pattern string is a pattern restart string defining the length of the pattern. The bits of an addressed pattern string and the associated pattern restart string are serially provided by the memory in response to an addressing counter. The bits of the pattern string are utilized for video inhibition to superimpose the pattern on a vector being generated. The bits of the pattern restart string are utilized to clear the counter when a preset restart bit is encountered in the string by the counter.
A data processing device for writing various kinds of rule data easily and rapidly in a pixel image memory. Rule pattern store means stores a plurality of kinds of rule patterns in the line direction and a plurality of kinds of rules in the digit direction, the line and digit directions respectively being associated with those of an image data store area of the pixel image memory. Means is provided for selecting one of the rule patterns stored in the rule pattern store means and moving it to the pixel image memory. In response to a command entered through an input device, desired one of the rule patterns is selected and only a desired length of the selected rule pattern is moved.
A graphics display unit providing rapid filling of predetermined areas of the display screen with one or more predefined repetitive patterns stored in the undisplayed portion of a frame buffer memory. The picture processor in executing a display list will encounter commands to load the predefined patterns(s) into the undisplayed portion of the frame buffer memory. The pattern is copied or replicated from there across the entire width of the frame buffer, with the final replication of the pattern being truncated. The display control unit fills the predetermined shapes or areas of the image to be displayed with the pattern(s) thusly loaded into the frame buffer memory, by copying sections of the scan lines of the replicated pattern up into the displayed section of the frame buffer specifically defining the shape to be filled-in. Pattern alignment between contiguous areas to be filled in with that pattern, is provided. Rapid filling is achieved by having the portion of the pattern coincide, scan line by scan line, with the image to be filled, in the X dimension. The replicated pattern becomes visible when the shape is drawn on the screen, with the shape acting as a window for viewing the pattern.
