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Dataplot Vol 1 Vol 2

X11

Name:
    X11
Type:
    Output Device Command
Purpose:
    Direct graphical output to an X11 graphics device.
Description:
    The X Window System is a computer independent protocol developed at MIT for supporting windowing and graphics applications in a networked environment. X is emerging as an industry standard and is now supported by most workstation vendors. The X11 driver has been successfully implemented on Release 3, Release 4, Release 5 and Release 6 of X11.
Syntax 1:
    X11

    This form designates device 1 as an X11 graphics device.

Syntax 2:
    DEVICE <1/2/3> X11

    This form designates one of Dataplot's 3 devices (typically device 1) as an X11 device.

Examples:
    X11
    DEVICE 1 X11
Note:
    Dataplot must be linked with the proper X11 libraries in order for the X11 driver to work. If this is not the case, contact your local Dataplot installer.
Note:
    A powerful feature of X is the ability to work in a networked environment. Dataplot can use X11 in one of two ways:

    1. Dataplot is installed on a local workstation (e.g., a SUN). In this case, simply enter the DEVICE 1 X11 command to open a graphics window. This assumes that X11 is installed on your local workstation. Check with your system administrator if you are not sure.

    2. Dataplot is installed on a remote host and the graphics will be generated on a local workstation or X11 terminal. Two typical configurations are a workstation running Dataplot from a mainframe or a group of workstations linked in a common network with Dataplot installed on one of these workstations. In this case, X11 must be installed on both the remote host and the local host and the following steps are required:

      • Enter the following from your local workstation:

        xhost + (entered from your local workstation)

      • rlogin or telnet to the remote host

      • Enter the following command before executing Dataplot:

        setenv DISPLAY :0

      The xhost command gives the remote host permission to write to your display. The setenv command identifies the specific workstation the remote host should generate the graphics on. Non-Unix hosts may have a different command than setenv.
Note:
    The dataplot command can be executed from any currently open X11 window. Dataplot's alphanumeric input and output, such as entering commands and the printing of FIT results, occurs in this window. Dataplot makes no effort to determine or manipulate the attributes of the alphanumeric window. When the DEVICE 1 X11 command is entered, a separate graphics window is opened. Both the alphanumeric and graphics windows can be controlled (i.e., moved, resized, exposed) with standard window manager menu options. In addition, the Dataplot commands PICTURE POINTS and ORIENTATION can control the size and shape of the graphics window. If the window is resized, the new dimensions do not take effect until the next screen erase is performed (this can be forced with a Dataplot erase command). Until the screen erase is done, graphics may either be clipped or only use a part of the available window.
Note:
    In X11, the window manager is simply another application program. This means that different implementations of X11 can use different window managers. There may be minor differences in how the Dataplot graphics window interacts with different window managers. However, Dataplot is written using the lowest layer of the X11 libraries (xlib), so it should be compatible with any of the window managers. The popular OpenLook (from Sun and AT&T) and Motif (most other vendors) window systems are X11 based and the X11 driver works with them.
Note:
    X11 supports graphical user interfaces. However, Dataplot simply supports X11 as a graphics device driver.
Note:
    Several SET commands were added to support X11 specific features.

    1. SET X11 NAME <display name>:

      Normally, X11 sends the graphics to the default display (for Unix systems, this is the "setenv DISPLAY" variable). This SET command is used to override the default display name. On Unix systems, this command is the equivalent to doing the Unix command "setenv DISPLAY <name> The name is given in one of the following 2 formats:

        SET X11 NAME dogwood.cam.nist.gov:0
        SET X11 NAME 129.6.80.44:0

      The numeric address should always be recognized. The name (and any abbreviations of the name) depend on the host tables on the specific machine.

    2. SET X11 PIXMAP <ON/OFF>

      If all or part of the Dataplot graphics window is covered and then re-exposed, the current graph is not automatically redrawn. If the PIXMAP variable is turned on, graphs are written to a pixmap in the background as well as to the screen. If part of the current graph is lost, the pixmap is copied to the screen to restore the current graph (the updating does not occur until the next command is entered). This option is recommended.

    3. SET X11 FONT <font name>

      The X11 font name can be up to 80 characters long. The following are terminal emulator fonts that should be available on most X11 systems.

        6x10
        6x12
        6x13
        8x13
        8x13bold
        9x15
        fixed
        variable

      In addition, most X11 implementations provide a large number of additional fonts. The complete list available on a given implementation can be retrieved with the "xlsfonts" command. Since the list of fonts varies with the implementation, Dataplot provides no abbreviations of the font names (which tend to be long).

    4. SET X11 CAP <BUTT/ROUND/PROJECT/NOTLAST>
      SET X11 JOIN <MITER/ROUND/BEVEL>

      The cap style determines how the end of lines are drawn (referred to as end-caps). For BUTT, the end-caps are squared off at end-points perpindicular to the slope of the line. The NOTLAST option is equivalent to BUTT for wide lines. For one pixel wide lines, the last point is not drawn. The ROUND option draws the end-cap as a circle with diameter equal to the line width. The PROJECT option draws a squared off end-cap, but it projects half the line-width beyond the endpoints. The join style controls how intermediate points of a polyline are connected (only if the line is more than one pixel wide). The MITER option extends the outer edges so that they meet at the same angle as would narrow lines. The ROUND option rounds off corners using a circle with diameter equal to the line width centered at the join point. The BEVEL option joins the lines as if they both had BUTT end-caps. In most cases, the cap and join style can simply be defaulted (BUTT and MITER respectively). The other choices are aesthetic preferences. Occasionally, curves that meet at sharp angles can produce spikes, in which case specifying a join style of ROUND or BEVEL should solve the problem.

    5. SET X11 PAUSE <ON/OFF>

      If this switch is ON, when a screen erase is performed on the X11 graphics window the user will be prompted to enter a carriage return.

      This switch is OFF by default.

      Note: This command is currently de-activated.

    6. SET X11 WINDOW ID <string>

      This command is used by the Tcl/Tk Graphical User Interface (GUI) when the GUI screen graphics are generated to an X11 window (rather than using the Tcl/Tk driver). This command is typically not entered by the user. If the user enters this command manually, it will probably result in the graphics not being displayed on the X11 window of the GUI.

Note:
    The 2023/11 version of Dataplot added support for scalable fonts. This is provided via the Xft library.

    To specify the use of scalable fonts, enter the commands

      set x11 font type scalable
      set x11 scalable font <font-name>

    Dataplot does no error checking as to whether or not a valid font name was entered. Typically, the font can be entered with a family name plus a list of attributes. For example

      set x11 scalable font LiberationSans-Regular:weight=bold:antialias=true

    Here, "LiberationSans-Regular" is the font family, weight specifies that the "bold" version of the font will be used and "antialias=true" specifies that the text will be drawn with anti-aliasing (this can sharpen the text).

    Some common options are

      weight=<light/medium/demibold/bold/black>
      slant=<roman/italic/oblique>
      spacing=<proportional/mono/charcell>
      antialias=<true/false>

    Dataplot will append a "size=" to the end of the font string based on the requested character size.

    Note that if the requested font is not matched exactly, the Xtf library will try to match it to the "closest" avaiable font.

    To see a list of available font family names, enter

      fc-list : family | sort

    To see what a font family will be matched to, enter something like

      fc-match Arial
Note:
    Dataplot automatically determines if the X11 device is color. The X11 driver supports the full range of colors available with Dataplot (about 88 colors and 100 levels of gray scale). Enter HELP COLOR for a list of available colors.
Default:
    Off
Synonyms:
    None
Device Notes:
    1. HARDWARE TEXT - A large number of hardware fonts are available (use the SET X11 FONT command). The 6x12 font is the default. A given font has a fixed size and rotation, so the only way to change the character size is to change the font.

    2. COLOR - X11 devices vary in their support of color (from monochrome to full 24-bit color). For color workstations, Dataplot will try to assign all 88 colors. Colors that are not available on the device are set to black (or white for black backgrounds). Gray scale is supported if the device itself supports it.

    3. HARDWARE FILL - Solid area fills are done in hardware.

    4. DASH PATTERNS - The following dash patterns are available:
        DASH - 6 pixels on, 3 pixels off;
        DOT - 1 pixel on, 2 pixels off;
        DASH2 - 9 pixels on, 3 pixels off, 3 pixels on, 3 pixels off;
        DASH3 - 3 pixels on, 3 pixels off;
        DASH4 - 2 pixels on, 4 pixels off.

    5. LINE WIDTH - Thick lines are generated in hardware.

    6. GRAPHICS INPUT - The CROSS-HAIR command is supported for this device.
Related Commands:
    POSTSCRIPT = Direct graphical output to a Postscript device.
    HPGL = Direct graphical output to an HPGL device.
    TEKTRONIX = Direct graphical output to a Tektronix device.
    DEVICE = Specify certain actions for the graphics output.
Applications:
    Graphics Output
Implementation Date:
    1990/04
    2023/04: Support for scalable fonts using the Xtf library
Program:
     
    DEVICE 1 X11
    PLOT X**2 FOR X = 1 1 9
        
Date created: 06/09/2016
Last updated: 11/17/2023

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