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

EN The HP-GL/2 Coordinate System 17-15
The HP-GL/2 Coordinate System
Both PCL and HP-GL/2 use a Cartesian Coordinate System. The
Cartesian coordinate system is a grid formed by two perpendicular
axes, usually called the X-axis and Y-axis (refer to Figure 17-4). The
intersection of the axes is called the origin of the system and has a
location of (0,0). The default HP-GL/2 coordinate system is different
than the PCL coordinate system; +Y is down in PCL and up in
HP-GL/2. In addition, the default origin is at the lower left in HP-GL/2
and at the upper left in PCL.
Note The HP-GL/2 coordinate system can be set up to match the PCL
coordinate system. See the example entitled “Adapting the HP-GL/2
Coordinate System to Match the PCL System” in Chapter 19.
Figure 17-4 The HP-GL/2 Coordinate System
To locate any point on the grid (the printing area within the PCL
Picture Frame), move from the origin a number of units along the
X-axis, then move a number of units parallel to the Y-axis. The
number of units you move matches a coordinate location. Each
point is designated by the combination of its X-coordinate and
Y-coordinate, known as an X,Y coordinate pair. In , positive X
values are plotted to the right of the origin, and positive Y values
are plotted above the origin.