hpgl(width=10, height=7.25, ask=!auto, auto=F, color=2, speed=400, rotated=F, file="", hw.control=T)
"GO?"
prior to advancing
to a new frame?
0
means that color changes are ignored,
1
means to prompt the
user when color changes (to allow manual pen changes, etc),
2
means that the device has automatic color changing capability.
hw.control
to
FALSE
when the output will be imported into another software
package.
This function works with plotters which accept the Hewlett-Packard HP-GL
instruction set.
This includes H-P pen plotter models 7220, 7470, 7475,
7550, and 7225.
The plotters may be used with standard 8.5 by 11 inch paper with the
long dimension horizontally or vertically, or
with other paper sizes by means of arguments
width
and
height
.
If
auto
is
FALSE
,
then whenever a new plot is about to be produced, the message
"GO?"
appears
on the terminal. At this time, new paper may be loaded, pens changed,
etc. When ready for plotting to proceed, simply hit carriage return.
When graphic input (
identify
,
locator
) is requested, the
enter
button will light. The pen should be positioned by means of the 4
directional buttons. When the desired pen position is reached,
depress the
enter
button. To terminate the input, hit carriage
return on the terminal. The coordinates of the terminating point are
not transmitted.
Character sizes may be changed to any desired value. Color can be
changed to any of the values
1
to
8
, indicating the pens in stables 1
to 8. Characters can be rotated to any orientation. Different line
styles (1, 2, ...) are available, with patterns becoming more spread-out
as the line style is larger.
Always be sure that the pen is capped when you are done
with the plotter.
The switches on the back of the device should be set to reflect
the correct speed and parity settings for the computer system;
incorrect parity settings may cause failures of digitizing functions, e.g.,
locator
and
identify
.
Do not allow two different instances of a graphics device write to the same file. The file will become corrupted if this happens.