; docformat = 'rst'
;
; NAME:
;   PS_Background
;
; PURPOSE:
;   Provides a device-independent way to set the background color in the PostScript device.
;
;******************************************************************************************;
;                                                                                          ;
;  Copyright (c) 2010, by Fanning Software Consulting, Inc. All rights reserved.           ;
;                                                                                          ;
;  Redistribution and use in source and binary forms, with or without                      ;
;  modification, are permitted provided that the following conditions are met:             ;
;                                                                                          ;
;      * Redistributions of source code must retain the above copyright                    ;
;        notice, this list of conditions and the following disclaimer.                     ;
;      * Redistributions in binary form must reproduce the above copyright                 ;
;        notice, this list of conditions and the following disclaimer in the               ;
;        documentation and/or other materials provided with the distribution.              ;
;      * Neither the name of Fanning Software Consulting, Inc. nor the names of its        ;
;        contributors may be used to endorse or promote products derived from this         ;
;        software without specific prior written permission.                               ;
;                                                                                          ;
;  THIS SOFTWARE IS PROVIDED BY FANNING SOFTWARE CONSULTING, INC. ''AS IS'' AND ANY        ;
;  EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES    ;
;  OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT     ;
;  SHALL FANNING SOFTWARE CONSULTING, INC. BE LIABLE FOR ANY DIRECT, INDIRECT,             ;
;  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED    ;
;  TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;         ;
;  LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND             ;
;  ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT              ;
;  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS           ;
;  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.                            ;
;******************************************************************************************;
;
;+
; :Description:
;   Provides a device-independent way to set the background color in the PostScript device.
;
; :Categories:
;    Graphics, Utilities
;    
; :Params:
;    color: in, required, type=string/integer, default='white'
;         The color that is used for the PostScript background. A polygon of
;         this color is written to the PostScript file and fills the PostScript
;         "window".
;          
; :Examples:
;       IDL> PS_Background, 'rose'
;       
; :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, 17 November 2010. DWF.
;        Modified to use gcColorFill so that color is done with decomposed color. 24 Dec 2010. DWF.
;
; :Copyright:
;     Copyright (c) 2010, Fanning Software Consulting, Inc.
;-
PRO PS_Background, color

   Compile_Opt idl2
   
   On_Error, 2

   ; Set default color, if not passed in.
   IF N_Elements(color) EQ 0 THEN color = 'white'
   
   ; Create a background color.
   TVLCT, rr, gg, bb, /GET
   IF StrUpCase(color) NE 'WHITE' THEN BEGIN
      cgCOLORFILL, [1, 1, !D.X_Size, !D.X_Size, 1], $
                     [1, !D.Y_Size, !D.Y_Size, 1, 1], $
                     /DEVICE, COLOR=color
   ENDIF
   TVLCT, rr, gg, bb
END