Using handcalculated data to print graphics

You can now perform the simplest application of graphics-using hand-calculated data to print graphic images. While this method is the most tedious, it helps you understand dot graphics. Also, it is useful for small graphic elements that are used many times.

Figure 6-3 shows how you can use a grid to plan where you want dots to be printed. This grid represents a single line of graphics 42 columns long. Since each line of 24-pin graphics is approximately 1/8th of an inch high, and since triple-density graphics prints 180 dots per inch horizontally a design planned on this figure will be about 1/8th of an inch high and less than 1/4th of an inch wide.

The actual pattern that the LQ prints on the paper is made up of dots that overlap both vertically and horizontally The planning grid uses an X for each dot, but remember that each X represents the center of a dot, and that the dots actually overlap each other.

Fgure 63.

Panern on grid

Graphics and User-defined Characters

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