Plotter Graphics - Epson FX-80 User Manual

Chapter 15
Plotter Graphics
As you explore the world of dot graphics, you may run into printer
limitations. For instance, dot-matrix printers are designed for fast
printing of text. They can also print high-resolution graphics, as you
saw in the logo program. But the side-to-side motion of a dot-matrix
printer makes it difficult to place the print head in the middle of a page
and trace out a lazy spiral or even a circle.
Does that mean the FX-80 can't create the same type of figures as a
plotter? Certainly not! You just have to approach the problem a little
differently than you would in working with a plotter. In fact, with a
little advanced planning, you can use the dot graphics modes to simu-
late the activity of a full fledged plotter.
The secret to bringing out the plotter in your FX-80 is to apply the
talents of your computer. After all, your printer and computer are
getting along famously. The computer has a large amount of memory
that can be used as a sketch pad. Using mathematical formulas, you
can sketch all sorts of crazy patterns in any direction you choose.
When the picture is complete in memory, it can be sent line by line to
the printer. When you use this approach, the printer doesn't have to
act like a plotter to produce like one.
The figures plotted (er, printed) in this chapter show how easy it is
to simulate "plotter graphics" with the FX-80. We start by using the
computer's memory as a sketch pad for our plotting. To do this, we set
up a correspondence between the desired pattern of dots on paper and
the computer's memory, as in Figure 15-1.
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