Sharp MZ-800 - Page 119

CIRCLE
Format
Explanation
Example
CIRCLE [<colour specification>] <X-coordinate>, <Y-coordinate>,
<radius> [,[<aspect>] [,<start>,<end>][,O]]
<colour specification> = [<palette code>)[,<superimpose mode>]
Abbreviated Format
Cl.
The CIRCLE statement draws an ellipse (circle) or arc (fan). The meanings cf the
<colour specification > parameter are identical to those of the SET statement. When
this parameter is omitted, the values specified by the COLOR statement are assumed.
<X-coordinate> and <Y-coordinate> give the coordinates of the center of the
circle and <radius> the radius of the circle. Their ranges of values are as follows:
~ 16384 = <coordinates> < 16383
0s <radius> < 16383
The area in which the circle can be actually displayed is determined by the INIT
command,
<aspect> affects the ratio of the X-radius to the Y-radius. When <aspect> is
less than 1, the <radius> specified becomes the X-radius. If aspect is greater than
1, then <radius> becomes the Y-radius. The default value of <aspect> is 1.
The <start> and <end> angle parameters specify where drawing of an ellipse
is to begin and end. These parameters must be given in radians. When omitted, an
ellipse (circle) is drawn. When the O parameter is specified with <start> and
<end>, a fan is drawn, that is, an arc is connected to the center point with lines.
When O is omitted, an arc only is drawn.
10 INIT’;CRT:M1”
20 CIRCLE[1,0]100, 100,80,0.5
30 GOSUB 80
40 CIRCLE([2,0]50,130,60,0.5,0,4/4,0
50 GOSUB 80
60 CIRCLE 159,99,50
70 END
80 GET AS:IF AS="' ’ THEN 80
90 RETURN
The above program draws an ellipse, and, if any key is pressed, it draws an arc,
then a circle.
SET, GET
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