2001/10/02
CHAPTER 9 HP-GL - 11
AA - Draw absolute arc
AA [ X, Y, qc [, qd ]] [;]
X ; Arc centre X coordinate
Y ; Arc centre Y coordinate
qc ; Arc angle in degrees
qd ; Chord angle in degrees
•
X and Y coordinates are absolute coordinates in user units or graphics units.
•
Starting from the current position, plots an arc centred on the absolute coordinates X, Y having the specified
arc angle and chord angle, with the radius being the distance between the current position and the point X,Y.
•
After plotting, the cursor position moves to the plot end point.
•
Plotting is performed only when the pen is down.
•
When the pen is up, plotting is not performed but the cursor position moves to the plot end poin t.
•
When scaling has been performed, the cursor is moved by absolute coordinates in user units.
•
Also, when scaling has been performed, the values for
X
and
Y
are real numbers.
•
When there is no scaling, the cursor is moved by absolute coordinates in graphics units.
•
When there is no scaling, the coordinate values for X and Y are integer number.
•
The value for pc is a clamped real number.
•
When
qc
is positive, counterclockwise plotting from the current point is performed.
•
When
qc
is negative, plotting is made clockwise from the current position.
•
The value for
qd
is a clamped real number.
•
When
qd
is not specified, the chord angle is the default value ( 5 degrees ).
(X,Y)
qc = Arc Angle
qd = Chord Angle
10 '*** AAEX ***
20 LPRINT "IN;SP1;IP2650,1325,7650,6325;"
30 LPRINT "SC0,100,0,100;"
40 LPRINT "PA0,30;"
50 LPRINT "PD;PA0,45;AA0,50,180;PA0,70;"
60 LPRINT "AA0,100,90;PA45,100;AA50,100,180;PA70,100;"
70 LPRINT "AA100,100,90;PA100,55;AA100,50,180;PA100,30;"
80 LPRINT "AA100,0,90;PA100,55;AA100,50,180;PA70,100;"
90 LPRINT "AA100,0,90;PA55,0;AA50,0,180;PA30,0;AA0,0,90;"
100 LPRINT "PU;PA50,50,CI20;"
110 END
<Sample 68>
AR - Draw relative arc
AR X, Y, qc(, qd)[;]
X ; Arc centre X coordinate
Y ; Arc centre Y coordinate
qc ; Arc angle in degrees
qd ; Chord angle in degrees
•
X and Y coordinates are relative coordinates in user units or graphics units.
•
Starting from the current cursor position the command plots an arc whose centre is at the relative coordinate
position (X,Y) and which has the specified arc and chord angles. The radius of the arc is the distance
between the current position and the point (X,Y).
•
After plotting the cursor position changes to the plot end point.