Chapter 4

So what does all this higher mathematics have to do with graphics? Just this. If we are to create high-resolution graphics on the MX-70, we have to eliminate the “dead space” between letters by changing the automatic line spacing to some value less than l/6 inch. We certainly don’t want a blank space 5 dots high between our rows of graphics!

The Line Spacing is Variable

Now that we understand the dot matrix concept and standard 12 dot “top-to- top” vertical spacing, let’s learn how to change it to suit our specific needs.

Type in this NEW program:

9 PR # l

 

 

(Apple)

20

PRINT

"LINE

ONE"

 

30

PRINT

"LINE

TWO"

 

40

PRINT

"LINE

THREE"

 

49

PR #0

 

 

(Apple)

and RUN.

 

 

 

 

 

 

 

L I N E

O N E

 

 

 

L I N E

T W O

 

 

 

LINE THREE

Figure 4-5

Nothing new here. Just like we’re used to.

Let’s all add line 10:

10 PRINT CHR$ (27) "A" CHR$ (12)

(or 12 + 128 = 140)

and RUN.

Same as before. Nothing changed. Then what is line 10 all about?

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