Generating The Array (Phase One) - Epson FX-80 User Manual

Ongoing generation of graphics in memory can easily be thought of
as a process with five "phases": generating the array; calculating the
pin patterns; setting the width; printing the figure; and working out
variations. Our discussion follows these phases.
Generating the Array (Phase One)
Since this program is fairly long, we only ask you to run it periodi-
cally, and we'll let you know when. Begin by defining variables.
NEW
1~
DIM
A(48~):
X=l:
C=~
2~
MAX=5: MIN=l: RE=4:
N=~
The array A, which is DIMensioned in line 10, will store the pattern.
The variables in line 20 are used in program loops to control the size
and shape of the figure. You can change these values later to create
your own variations on the pattern.
Table 16-1 lists the variables for easy reference.
Table 16·1. Variables for SYMMETRY Program.
Variable
Purpose
A Array
C
Counter of array elements
DOT Counter of dots; used to calculate P
H
Highest number used in calculating P
J Loop counter
K
Loop counter
L
Loop counter
LAST Last pass of the print head
MAX
Maximum number for the pattern
MIN
Minimum number for the pattern
N Number of pins in the current pattern
N1
Length of the graphics line
N2
Length of the graphics line
P Pin firing pattern
PO
Reverse pattern of P
PASS Number of the current pass
R Remainder
RE Number of repeats of the pattern
X
o
or 1 to fill the array
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