Epson FX-80, Руководство пользователя

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Chapter 13
Plotter Graphics
As you work with dot graphics, you may run into printer limita-
tions because dot-matrix printers are designed primarily for fast print-
ing of text. The FX, however, can also print high-resolution graphics,
as you saw in the STRATA program. But the side-to-side motion of a
dot-matrix printer makes it virtually impossible 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 can’t create the same type of figures that a
plotter does? 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 advance planning, you can use the dot graphics modes to
simulate the activity of a full-fledged plotter.
The secret to bringing out the plotter in your FX is to apply the
capabilities of your computer system. You can use its memory as a
sketch pad. With mathematical formulas, you can design any sort of
pattern. Once you’ve got your picture complete in memory, you can
send it line by line to
the
printer. When you use this approach, the
printer doesn’t have to act like a plotter to draw like one.
The figures printed in this chapter show how easy it is to simulate
plotter graphics with the FX. You start by using the computer’s mem-
ory as a sketch pad for the plotting. To do this, you set up a correspon-
dence between a pattern of dots on paper and a set of values
that you
arrange in the computer’s memory (Figure
13-1).
Arrays
The structure in computer memory in which you store your pattern
of dots is called an array. Think of an array as an ordered set of cubby
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