7.5

Arc and ArcN (procedures)
Arc()draws an arc in a counter-clockwise direction, while ArcN()draws an arc in a clockwise direction. If there is a current
point set, the command draws a straight line from the current point to the start point of the arc. Whether or not a current point
is set when the command executes, after execution the current point is the end point of the arc.
You define the arc you want to draw by specifying the x and y coordinates of the center of the circle, the radius of the circle,
and the start and end points for the arc. You specify each of the start and end points of the arc as an angle; the command uses
the angle to position the point. For example, to position the start point, the command draws an invisible line at the specified
start angle from the center of the circle, the length of the radius; it positions the start point at the end of that line.
Example using Arc() Example using ArcN().
Example of an arc drawn from start point D to end point F: A. Center of circle (x,y) B. Radius C. Start angle D. Start point of arc
E. End angle F.
Syntax
arc( x, y, arc_length, start_angle, end_angle )
Arguments
x, y
Measure values representing the x and y coordinates respectively of the center of the circle.
arc_length
Measure value representing the length of the arc.
start_angle
Measure value representing the start angle, in degrees, for the arc. Degrees are relative to a standard X, Y axis, with a value
of 0 degrees lying flush with the X axis. The value of the start angle can be either positive or negative.
end_angle
Measure value representing the end angle, in degrees, for the arc. Degrees are relative to a standard X, Y axis, with a value of
0 degrees lying flush with the X axis. The value of the end angle can be either positive or negative.
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