Brother HL-3040CN Reference Guide

Page of 512
 
CHAPTER 4 HP-GL/2 - 7 
3.
 
TERMINOLOGY 
3.1.
  Picture Frame 
The printer frame is the rectangular area of the page on which graphic output can be printed.    This is based 
on the logical page defined for the selected paper size. 
 
3.2.
  Anchor Point 
The anchor point of the picture frame is the top left hand corner of the frame.    This can be moved on the 
page using PCL language page control commands. 
 
3.3.
  Graphics Window 
The graphics window is the rectangular area of the page on which you can generate graphic output using 
HP-GL/2 commands.    Initially the graphics window is the same as the picture frame but may be altered 
using the HP-GL/2 IW command. 
 
3.4.
  Hard Clip Limits 
Hard clip limits are the physical restrictions which define where printed output can appear on a page. 
 
3.5.
  Soft Clip Limits 
Soft clip limits are the user-defined restrictions which define where printed output can appear on a page. 
 
3.6.
  Graphics Units 
The initial coordinate system employs units of 1/1016" in both the x- and y-axes.     
 
3.7.
  User Units 
The HP-GL/2 graphics language uses a coordinate system.    You can impose your own x- and y-scale units 
on this system using the SC command. 
 
3.8.
  Current Units 
The units in use at a given time are called the current units.    Current units are either user units or graphics 
units,    depending on whether scaling has been turned on or not.    The SC command is used to turn scaling 
on,    that is,    to make user units the current units. 
 
3.9.
  Pens 
By convention, certain HP-GL/2 graphics language commands are thought of as using a pen,    which can 
be either up or down.    To produce plotted output the pen must be down.    To move to a location on the 
page without producing output the pen must be in the up position.    Some HP-GL/2 commands require you 
to specify the pen position before you use them, others have implied pen positions built into them,    so that 
you do not need to specify "Pen up" or "Pen down".