- M. C. Shepherd, 1994.
- Supported device
- All workstations running the X Window System
(Version 11 Release 4 and above) under UNIX, VMS and
- Device type codes
opens a window that disappears when PGEND is
opens a window that persists for reuse after
PGEND is called.
default X display name defined by one's environment.
Under UNIX this is given by the
Under VMS it is the device last created with
The device name specifies the X-window display to
use, the screen of that display and the PGPLOT
window number to use.
window number is a small integer
used to identify individual windows created by
PGPLOT. You can either specify the number of an
existing inactive window to reuse, or provide a new
number to assign to a new window. If the number is
omitted or specified as zero, then either the last
window to become inactive will be reused, or a new
window will be created and assigned the lowest
unused window number. The number of each window is
displayed in the title of the window.
host part of the specification
is the address of the host on which the display
resides. If a DECNET address is used, the host name
should be separated from the display number by two
colons instead of one.
display part of the
specification is the number of the display server on
the given host. Usually this is 0, but if you have
multiple X terminals connected to the same machine,
then each terminal is generally assigned a different
screen number is also usually 0,
but if your display has multiple screens, then each
is identified by a small integer.
For example "
opens PGPLOT window 2 as a
window on host
that the @ symbol is optional if the display name is
omitted. Thus "
2/xw" opens window 2 on
the default display.
view surface dimensions
default geometry of each window is specified in
pixels, using the following hierarchy of
specifications. Missing details at each level are
supplied by those below.
- X resource:
- X resource:
- Environment variable:
[fractional display width]
- Width=867, height=669 and aspect=8.5/11.
Once displayed, the window can be resized with the
mouse, but the drawing area is only resized to
reflect this when the next page is started.
- Depends on
of types PseudoColor, StaticColor, GrayScale,
StaticGray, and TrueColor are supported. By default,
the first available colormap from one of the following
lists is used.
color displays: PseudoColor, StaticColor,
gray-scale displays: GrayScale, StaticGray.
monochrome displays: The default colormap of
Thus, where possible a read/write colormap is
chosen. This allows color representation changes via
PGCTAB, PGSCR and PGSHLS to be applied immediately
to previously drawn graphics, which makes it
possible to interactively fiddle the colors when
used in conjunction with PGBAND.
If the first available colormap type happens to
match that of the default colormap of the screen,
and enough colors are available therein, then that
colormap is used. Otherwise, allocation of a private
colormap is attempted. If this fails, the device is
treated as monochrome. The default color-map type
can be overriden via the
resource described below. However, if the requested
colormap type is not available, the driver reverts
to its default colormap search strategy.
By default the driver tries to allocate 100
colors. This number usually makes it possible to
have two windows displayed simultaneously without
having to allocate a private colormap. This helps to
avoid colormap flashing as the pointer is moved
between windows. You can override this default with
a number in the range 2 to 255 by using the
- The cursor
is usually controlled by a mouse. Cursor input is
achieved by moving the cursor into the window, and
pressing either a mouse button or a keyboard key to
select a given position in the window and return a key
value. The mouse buttons are mapped to return
characters A, D, and X. The cursor can also be moved
horizontally and vertically with the keyboard arrow
keys: each keystroke moves the cursor by one pixel, or
10 pixels if the SHIFT key is depressed.
Rubber-banding is supported: see routine PGBAND. With
Click-to-focus window managers you may have
to explicitly click on the window to enable keyboard
input in the PGPLOT window.
following optional X window resources can be used to
specify configuration options. On POSIX-compliant
systems, these should be placed in a file called
in your home directory. Under VMS they should be
Note that by default DECW$USER_DEFAULTS is defined as
SYS$LOGIN. Resource specification is discussed further
in the "Potential problems" section further
The following resource descriptions show how a
resource line should be constructed in one's
resource file. Where default values are available
they are indicated. Otherwise the value is indicated
symbolically and instructions are given for
substituting appropriate values.
- This specifies the size and position of a window
in pixels. Any of the above components can be
omitted. The X and Y values specify the position
of the top left corner of the window wrt the top
left corner of the screen, if positive, or the
bottom right corner wrt the bottom right corner,
- This specifies the position of the iconized form
of a window, in pixels. The X and Y values specify
the position of the top left corner of the window
wrt the top left corner of the screen, if
positive, or the bottom right corner wrt the
bottom right corner, if negative.
- Most window managers provide a way for the user
to destroy a window using the mouse, often via an
option in a pull down menu. By default PGPLOT
takes steps to ignore this action when a window is
actually being used by a PGPLOT program. To
re-enable it, set:
- By default, PGPLOT /XSERVE windows remain mapped
when PGEND is called or when the program is
terminated. If instead you wish the window to be
iconized until opened by a new PGPLOT program,
- This specifies the maximum number of colors that
PGPLOT tries to allocate for each X window.
Reducing the number of colors allocated makes it
more likely that each window will share the same
colormap and thus stop ``colormap flashing''. Note
that the value of the maxColors option must not be
less than that of the minColors resource described
- To reject colormaps with fewer than a given
number of color entries, specify the minimum
number of colors required.
you have a preference for the type of colormap to
use, specify the name of the preferred type.
PGPLOT will then try that type first. The
following type names are recognized:
- Use the colormap search strategy
described in the "Color Capability"
- Use black and white.
- Read/write color visual.
- (This is treated as an alias for
- Read-only color visual.
- Read-only color visual (3 primary
- Read/write gray-scale visual.
- Read-only gray-scale visual.
augment the default active PGPLOT cursor with
cross hairs, set:
hide the PGPLOT server window set
specifies the position of the server window icon
on the X display, in display pixels. The X and Y
values specify the position of the top left corner
of the window wrt the top left corner of the
screen, if positive, or the bottom right corner
wrt the bottom right corner, if negative.
Note that resource specifications that start with pgxwin.Win
apply to all PGPLOT /xwindow and /xserve windows. To
target options at specific windows, replace the Win
component of the specification with win#,
where # is the number of the PGPLOT
window. For example:
stipulates that all windows except PGPLOT window 2
will use a crosshair for the default cursor. Note
that Win is spelt with an upper case
initial 'W', whereas win# is
spelt with an initial lower-case 'w'. This
is important because all resource names are case
example of the utility of targeting options at
specific windows is the following:
This example places the first PGPLOT window in one
position on the display, and all other windows in a
second location - thus avoiding obscuring the first
by the second etc..
Similarly if one wanted to dedicate one window to
line graphics, one could designate a specific window
number to have a reduced number of colors.
This window would then be selected using a device
specification of "10/xserve".
/XWINDOW and /XSERVE window server (pgxwin_server).
- All PGPLOT
/xwindow and /xserve windows on a single display are
created and maintained by a separate server program
called pgxwin_server. If PGPLOT has been installed
correctly then this program is automatically started
by the /xw and /xs driver when first called upon.
pgxwin_server then continues to serve windows to
subsequent PGPLOT programs and remains running
indefinitely. In order that it be possible to kill the
server, an icon window for it is displayed. Window
managers generally provide a way to interactively kill
windows, and if this is applied to the server window,
then the server will close any inactive /xserve
windows, and if no active /xw or /xs windows remain,
then the server will shut itself down cleanly. Note
that inactive windows are distinguishable from active
windows by the appearance of a skull-and-crossbones
pgxwin_server fails to start automatically, see the
"Potential problems" section below on how
to remedy this. However, if for some reason it is
necessary to run pgxwin_server manually, you'll need
to know the following. In particular, under VMS,
before you can run the server you will first need to
register it as a foreign command, by typing:
If your default display is correctly set then
with no arguments should start the server, and the
server icon should appear on the display. If an
alternate display is desired then the default
display can be overridden with the -display
argument. Other options to override selected X
resources from the command-line are also available.
To see them type:
server fails to start.
- If the server fails to start automatically then
this means that the /xw and /xs driver was unable
to find the pgxwin_server executable. It first
looks in the directory specified in your
PGPLOT_DIR environment variable (or LOGICAL
PGPLOT_DIR variable under VMS). Under UNIX, if it
fails to find the executable there, it then looks
for the executable in each component directory
cited in your PATH environment variable. To fix
the problem, first determine where the person who
compiled PGPLOT installed pgxwin_server and then
either place this directory name in your
PGPLOT_DIR variable or, under UNIX, add it to your
If you are still unable to get the server to
start automatically, please send me Email at email@example.com.
In the meantime, you can work around the problem
by starting the server by hand, as described
- X resource options are ignored.
First check check both the spelling and case of
your resource names. Resource names are case
sensitive and must appear exactly as
The X resource database is compiled by the
pgxwin_server program when it is started.
Resources set after it has been started are
ignored and pgxwin_server will need to be
restarted before they are acquired. There are a
number of places in which the server can find
resources, and your specifications will not be
seen if they appear in the wrong place.
pgxwin_server attempts to follow the rules laid
down by the X Toolkit. First it looks for a
RESOURCE_MANAGER property on the root window of
your display. This contains a list of resource
names and values and comes into being when the
standard xrdb program is applied to a resource
file. It is common for xrdb to be applied
automatically to your Xdefaults file, or to a
system supplied xdefaults file when the X server
is first started. If this is the case then
changes to your Xdefaults file will be ignored
until the server is restarted or you explicitly
re-run the xrdb command.
If - and only if - the RESOURCE_MANAGER
property does not exist, then under UNIX
pgxwin_server looks for a file called .Xdefaults
in your home directory, and under VMS it looks
for a file called
DECW$USER_DEFAULTS:DECW$XDEFAULTS.DAT. If it
finds this file, it initializes its resource
database from it. It then also looks to see if
the XENVIRONMENT environment variable contains a
valid file name and if so reads resources from
that file, overriding any contrasting resources
from your Xdefaults file.
To be sure that changes to resources in your
Xdefaults are seen by pgxwin_server you should
use the xrdb command to install them on the
$ xrdb -nocpp decw$user_defaults:decw$xdefaults.dat
If the xrdb command is not defined on your
system, then first execute:
Then terminate pgxwin_server by quiting its
icon and ask for /xw or /xs again to restart it.