Divide And Conquer - Epson FX Series User Manual

drastic measures. One such measure would be to let each bit of the
numbers stored in the array cells represent one graphics dot. This
would increase the storage ability but tremendously complicate the
programming.
For symmetric designs such as the circle, you can use a different
measure. Take advantage of the symmetry to increase your output
four-fold without increasing the size of the array one iota. How? By
using the array to plot one-fourth of the circle in memory, then modi-
fying the array three times to generate the remaining three parts (Fig-
ure 13-6).
Try this out with the current program. Here are the changes you
need to make to your current program in order to plot the lower-right
corner :
30
D=SQR(R^2+C^2)
40
IF INT(D+.5)=20 THEN A(R,C)=l
130
LPRINT CHR$(27)"*"CHR$(5)CHR$(N)CHR$(0);
By moving the center of the circle from
the radius from
182
Figure 13-7. Divide and conquer
to 20, you enlarge the figure.
10
to (0,O) and increasing
(11,ll)