# coyote: CGPSWINDOW

- coyote/Utilities
- coyote/Graphics
- [Source code]

Description

      This function is used to calculate the size of a PostScript window that has the same
      aspect ratio (ratio of height to width) as the current display graphics window. It
      creates the largest possible PostScript output window with the desired aspect ratio.
      This assures that PostScript output looks similar, if not identical, to normal
      graphics output on the display.

Categories

      Utilities, Graphics

Examples

      To create a PostScript output window with the same aspect
      ratio as the curently active display window, type::
         pageInfo = cgPSWINDOW()
         SET_PLOT, 'PS'
         DEVICE, _Extra=pageInfo
      To configure the PRINTER device::
         pageInfo = cgPSWINDOW(/Printer, Fudge=0.25)
         SET_PLOT, 'PRINTER'
         DEVICE, _Extra=pageInfo

Author

      FANNING SOFTWARE CONSULTING::
         David W. Fanning
         1645 Sheely Drive
         Fort Collins, CO 80526 USA
         Phone: 970-221-0438
         E-mail: david@idlcoyote.com
         Coyote's Guide to IDL Programming: http://www.idlcoyote.com

History

      Change History::
         Written by: David W. Fanning, November 1996.
         Fixed a bug in which the YOFFSET was calculated incorrectly
            in Landscape mode. 12 Feb 97.
         Took out a line of code that wasn't being used. 14 Mar 97.
         Added correct units keyword to return structure. 29 JUN 98. DWF
         Fixed a bug in how landscape offsets were calculated. 19 JUL 99. DWF.
         Fixed a bug in the way margins were used to conform to my
            original conception of the program. 19 JUL 99. DWF.
         Added Landscape and Portrait fields to the return structure. 19 JUL 99. DWF.
         Added PageSize keyword, changed MARGIN keyword, and completely
            rewrote most of the intenal code. 9 FEB 2000. DWF.
         Fixed a bug in how I calculated the aspect ratio. 1 MAR 2000. DWF.
         Added PRINTER keyword to return proper offset values for the
            PRINTER device, where the offset location is not rotated. 1 MAR 2000. DWF.
         Added PRINTER fudge factors to take into account that printer offsets are
            calculated from the printable area of the paper, rather than the corner
            of the paper. 8 AUG 2000. DWF.
         Changed the default margin to 0.05 from 0.15. 29 Nov 2004, DWF.
         Added EUROPEAN keyword and set LANDSCAPE mode if window wider than higher
             as the default if LANDSCAPE is not set. 13 Dec 2010. DWF.
         Added ASPECTRATIO keyword to allow user-specified window aspect ratio. 13 Dec 2010. DWF.
         Depreciated EUROPEAN keyword in favor of METRIC. 31 Jan 2011. DWF.
         Now setting LANDSCAPE=0 if aspect GT 1 and not set otherwise. 19 Feb 2013. DWF.
         Renamed cgPSWIndow from PSWindow. 10 Feb 2014. DWF.
         Added SANE_OFFSETS keyword. 10 Feb 2014. DWF.

Copyright

      Copyright (c) 1996-2014, Fanning Software Consulting, Inc.
       function produces a position vector in the output window, given
      sired aspect ratio and window size.

Returns

      The output value is a named structure defined like this::
         pageInfo = {CGPSWINDOW_STRUCT, XSIZE:0.0, YSIZE:0.0, $
            XOFSET:0.0, YOFFSET:0.0, INCHES:0, PORTRAIT:0, LANDSCAPE:0}
      The units of the four size fields are inches unless the CM or METRIC keywords
      are set. The output can be used to immediately configure the PostScript
      or Printer device, like this::
         Set_Plot, 'PS' ; or 'PRINTER'
         Device, _Extra=pageInfo

Params

      aspectRatio: in, optional, type=float, default=1.0
         The desired aspect ratio of the output "window" on the output device.
         The aspect ratio is calculated as the ratio height/width.

Keywords

      aspectRatio: in, optional, type=float, default=1.0
         The desired aspect ratio of the output "window" on the output device.
         The aspect ratio is calculated as the ratio height/width.
      cm: in, optional, type=boolean, default=0
          Set this keyword to return sizes and offsets in centimeters instead of inches.
      european: in, optional, type=boolean, default=0
          A depreciated keyword. Use `Metric` instead.
      fudge: in, optional, type=float
         A quick way to set symetrical XFUDGE and YFUDGE factors.
         If this keyword is set to a value, XFUDGE and YFUDGE keywords are
         set to the same value. Fudge factors are used only with some
         printers and generally only when output is being sent to the
         PRINTER device. See the description of the `XFudge` and `YFudge`
         keywords for additional information.
      landscape: in, optional, type=boolean, default=0
          Set this keyword to return sizes and offsets in landscape mode.
      margin: in, optional, type=float, default=0.15
         An optional margin to calculate around the edge of the output window.
         A number between 0.0 and 0.35.
      metric: in, optional, type=boolean, default=0
          Set this keyword to change the `Pagesize` to A4 and set the `CM` keyword for
          metric or European measurements.
      pagesize: in, optional, type=string, default='LETTER'
         Set this keyword to a string indicating the type of PostScript page size you want.
         Allowed values are "LETTER", "LEGAL", and "A4".
      printer: in, optional, type=boolean, default=0
         Set this keyword to produce keyword values appropriate for the PRINTER device.
      sane_offsets: in, optional, type=boolean, default=0.0
          Configuring the PostScript device when in Landscape mode is pretty much insane.
          The problem is the PostScript page rotates and the X and Y offsets change
          directions, although the X and Y sizes do not. Nevertheless, this is how it
          is done, so normally these insane, mixed up values are returned so they can be
          passed directly to the PostScript device. Coyote Graphics routines, however,
          reply on cgPS_Config to configure the PostScript device, and this routine uses
          sane offset values, which are *always* calculated from the lower-left corner of
          the display window, no matter how the page is rotated. If you are passing these
          values into cgPS_Config, you want to set this keyword.
      xfudge: in, optional, type=float
         Printers calculate the offset point from the printable
         edge of the paper (sometimes), rather from the corner of the paper.
         For example, on my Lexmark printer, both X and Y offsets are
         calculated from a point 0.25 inches in from the edge. This keyword
         allows you to set a "fudge" factor that will be subtracted from
         the XOFFSET that is returned to the user. This allows you to create
         output that is centered on the page. The fudge factor should be in
         the same units as the returned size and offset values.
      yfudge: in, optional, type=float
         Printers calculate the offset point from the printable
         edge of the paper (sometimes), rather from the corner of the paper.
         For example, on my Lexmark printer, both X and Y offsets are
         calculated from a point 0.25 inches in from the edge. This keyword
         allows you to set a "fudge" factor that will be subtracted from
         the YOFFSET that is returned to the user. This allows you to create
         output that is centered on the page. The fudge factor should be in
         the same units as the returned size and offset values.