BASIC FUNCTIONS
SECTION 5.4
5.4.4
. CIRCLE
Function CIRCLE draws a circle of given radius at the specified co-
ordinates.
Syntax CIRCLE [(X,Y,)] , r[ ,n]
O<X<239
O<Y<63
Example 10 FOR I = 20 TO 220 STEP 40
20 CIRCLE (I,32),20
30 NEXT
Will plot six circles across the display.
Remarks The optional parameter n will plot the circle in black if
it is odd, or erase the points if it is eve~ When
omitted, it defaults to odd. The co-ordinates may also be
omitted, and the circle is. then centred on the current
graphic cursor position. Circles plotted off the edge of
the screen will produce wrap around, Modulo 256.
The CIRCLE command range checks the x-coordinate, y-
coordinate and radius to be less than 256. Since the
HUNTER screen in graphics mode can only display 0-239 and
0-63 in the x and
y directions respectively, there are
occasions when the expected circle does not appear on the
screen.
VER.V09F
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