Xerox 4650, 4450 manual Importance of orderly construction, Example of extraneous drawn lines

TROUBLESHOOTING

Generally, the line table limits are reached because the form contains a large number of short line segments. The most probable reason for this is a series of vertical lines (for example, tick marks) or horizontal lines (for example, a series of long dashes). With either of these conditions, it is possible to reduce the number of entries in the line table as the form is being constructed.

Importance of orderly construction

One consideration in determining the orderliness of form construction is that the algorithm used in loading the line table is designed to check only the following two criteria before entering a new line in the line table:

·Is the new line contained within the boundaries of an existing line?

·Is the new line an extension of one of the existing lines?

If the new line is contained within the boundaries of an existing line, no change is made to the line table entries. If the new line is an extension of one of the existing lines, the boundaries of the first (and only the first) existing line are extended to include the new line. If neither of the criteria is met, a new entry is made in the line table.

Examples The procedure of line extension results in an irregularity if lines are not specified in an orderly manner. For example, draw five line segments that are each five units in length. If the lines are drawn in an unreasonable or irregular manner, as shown below, the result is more entries in the line table than are necessary. Drawing line segments in the order 0 to 5, 10 to 15, 20 to 25, 5 to 10, and 15 to 20 creates a single visual line that FDL considers to be three lines. This is because the criterion of the line table allows the extension of only the first line segment with common coordinates to the new line. In this case, the three line entries in the line table would be 0 to 10, 10 to 20, and 20 to 25. Figure 4-1 shows examples of extraneous drawn lines.

Figure 4-1.Example of extraneous drawn lines

It is also possible to have the line table show more than one line passing in the same direction through a given coordinate. For example, draw three lines, each of which is five units in length (0 to 5, 10 to 15, and 20 to 25). Then draw two lines, each of which is nine units in length (3 to 12 and 13 to 22). The result is a single visual line for which FDL has three entries in the line table (0 to 12, 10 to 22, and 20 to 25). Figure 4-2 shows lines entered in unintended locations.

XEROX 4050/4090/4450/4650 LPS FORMS CREATION GUIDE 4-5