HP PCL/PJL reference (PCL 5 Printer Language) - Technical Reference Manual Part II

20-48 The Vector Group EN
RT, Relative Arc Three Point
This command draws an arc segment, using relative coordinates,
from a starting point through an intermediate point to an end point.
Use RT when you know these three points of an arc.
RT X\incr inter,Yincr inter, X\incr end\,Yincr end[,chord angle;]
The RT command uses the current pen location and two specified
points to calculate a circle and draw the appropriate arc segment of
its circumference. The arc starts at the current pen location, using the
current pen, line type, line attributes and pen up/down status. You
specify the intermediate and end points. After drawing the arc, the
pen location remains at the end of the arc.
z X
Incr Inter
, Y
Incr Inter
— Specify the location of an intermediate
point of the arc in relative increments (relative to the current pen
location). The arc is drawn in a negative or positive direction, as
necessary, so that it passes through the intermediate point
before the end point.
z X
Incr End
,Y
Incr End
— Specify the location of the end point of the
arc in relative increments (relative to the current pen location).
z Chord Angle — Specifies the chord angle used to draw the arc.
The default is a chord angle of 5°. (The Arc Absolute command
description, earlier in this chapter, contains more information on
chords and chord angles.)
Intermediate and end point coordinates are interpreted in current
units: as user-units when scaling is on; as plotter units when scaling
is off. If current scaling is not isotropic, the arc drawn is elliptical rather
than circular. Note the following about intermediate and end points:
z If the intermediate point and end point are the same as the
current pen location, the command draws a dot.
z If the intermediate point is the same as either the current pen
location or the end point, a line is drawn between the current
pen location and the end point.
Parameter Format Functional Range Default
X
incr inter
, Y
incr inter
current units -2
30
to 2
30
- 1 no default
X
incr end
, Y
incr end
current units -2
30
to 2
30
- 1 no default
chord angle clamped real 0.5° to 180°