PSWorkstation class resource descriptions

This resource is used to specify which PostScript format should be produced. Currently, the PSWorkstation can produce generic "ps", EPS (Encapsulated PostScript) "eps", and EPSI (Encapsulated PostScript Interchange format) "epsi".

EPS is a specialized format used primarily for importing PostScript into other applications. EPS files contain information in them, that allow an importing application to know the extent of the marks on the PostScript page. They are also restricted to a single page of output in them.

EPSI are EPS files that have a "preview bitmap" that represents the PostScript image contained in the file. This bitmap can be used by an importing application to display quickly a picture of the imported file. This is used by applications that do not have a built-in PostScript interpreter. As of Version 4.0, the "preview bitmap" output by the PSWorkstation does not represent the picture contained in the EPSI file, but rather is simply a bitmap containing the message: APPLICATION CANNOT DISPLAY NCAR GRAPHIC HERE. VIEW THE POSTSCRIPT OUTPUT TO VERIFY SUCCESSFUL IMPORT.

Default: "ps"

wkVisualType

This resource is used to indicate if the PostScript file should produce "color", or "monochrome" output. Color output can be displayed on a grayscale printer, and the colors will be mapped to shades of gray. If "monochrome" output is selected, all colors, except the background color, will be mapped to the foreground color. If you are plotting a color image on a grayscale printer and find the results unsatisfactory since colors are getting mapped to light shades of gray that are difficult to see, it may be better to produce the picture in "monochrome".

Default: "color" wkColorModel

This resource specifies the color model used to describe colors in the output PostScript file. The choices are "rgb" for the Red-Green-Blue color model or "cmyk" for the Cyan-Magenta-Yellow-Black color model. Note that this resource affects the output file only. Elements of the wkColorMap array be set using the RGB model or named colors only.

Default: "rgb"

wkOrientation

This resource is used to indicate if the PostScript output should be produced in "portrait" mode (pictures displayed along the width of the paper or viewing window) or "landscape" mode (pictures displayed along the length).

Default: "portrait"

wkPSFileName

This resource is used to specify the name of the PostScript file to output. If a wkPSFileName of "stdout" is given, the PSWorkstation understands the output should be sent to the stream associated with the stdout FILE pointer in the UNIX environment. The PSWorkstation object will attempt to resolve pathnames that start with the "~" character.

Default: <dynamic>
This resource defaults to the name of the PSWorkstation object with the wkPSFormat as a suffix. For example, "workname.ps".

wkFullBackground

If this resource is True, then the entire output page will have the background color applied to it. If it is False, then only the normalized device coordinate viewport will be effected by the background color. The background is the first thing drawn on the page. Therefore, if this resource is modified after something has been drawn, it will not change the background for the current page. It will effectively change for the next page of the output.

Default: False

wkPSResolution

This resource indicates the resolution of the internal coordinate space of the PostScript file. This resource is used to increase or decrease the resolution of the output. The effective resolution you get on a particular PostScript printer or screen display depends on the resolution of the internal PostScript coordinate system as well as the resolution of the output device. The units of this resource are compatible with DPI (Dots Per Inch). If wkPSResolution is set to a number that is greater than or equal to the resolution of the printer, then you can be sure that you are making full use of the resolution of the printer. It is important to realize that printers that have a lower resolution can print PostScript files that have a higher internal coordinate space resolution without problems, since the internal coordinate space resolution just indicates the resolution of the points within the file's coordinate space. If the PostScript is generated with a lower internal coordinate space resolution then the printer, the full resolution of the printer will not be utilized.

One advantage of lowering the wkPSResolution would be to make the actual size of the PostScript file smaller, although the difference is rather modest.

Default: 1800

Positioning output on the page

The following resources specify where on the output page, the normalized device coordinate viewport should be placed. They indicate the Lower X, Lower Y, Upper X, and Upper Y values of the viewport. The values are specified in the default PostScript coordinate space where one unit corresponds to 1/72 of an inch. This means that an 8.5" x 11" page would be addressed from (0,0) in the lower left corner to (612,792) in the upper right corner (The page is always viewed in portrait mode for this purpose). In order to maintain aspect ratio (insure that circles do not become ellipses, and squares do not become rectangles), these values should indicate a square area of the page.

wkDeviceLowerX: Defines the Lower X value of the normalized device coordinate viewport on the page. It is specified in PostScript coordinate space where one unit corresponds to 1/72 of an inch. 0 addresses the left side of an 8.5" x 11" page, and 612 addresses the right side. For details on using the PostScript workstation positioning resources, see the appropriate section in the NCAR GKS User's Guide for NCAR GKS-0A Graphics. It is particularly important to consult the section in the GKS manual on using the full page if you are using the PostScript workstation positioning resources with a PostScript landscape workstation.
Default: 36
wkDeviceLowerY: Defines the Lower Y value of the normalized device coordinate viewport on the page. It is specified in PostScript coordinate space where one unit corresponds to 1/72 of an inch. 0 addresses the bottom side of an 8.5" x 11" page, and 792 addresses the top side.
Default: 126
wkDeviceUpperX: Defines the Upper X value of the normalized device coordinate viewport on the page. It is specified in PostScript coordinate space where one unit corresponds to 1/72 of an inch. 0 addresses the left side of an 8.5" x 11" page, and 612 addresses the right side.
Default: 576
wkDeviceUpperY: Defines the Upper Y value of the normalized device coordinate viewport on the page. It is specified in PostScript coordinate space where one unit corresponds to 1/72 of an inch. 0 addresses the bottom side of an 8.5" x 11" page, and 792 addresses the top side.
Default: 666

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