source: trunk/SRC/Colors/colorbar.pro

;+
;
; @file_comments
; The purpose of this routine is to add a color bar to the current
; graphics window.
;
; @categories
; Graphics
;
; @keyword BOTTOM {default=0B}
; The lowest color index of the colors to be loaded in the bar.
;
; @keyword CB_CHARSIZE {default=1.0}
; The character size of the color bar annotations.
;
; @keyword CB_CHARTHICK {default=1.0}
; The character thick of the color bar annotations.
;
; @keyword CB_COLOR {default=ncolors - 1 + bottom}
; The color index of the bar outline and characters.
;
; @keyword CB_LOG
; to get logarithmic scale for the colorbar
;
; @keyword CB_TITLE {default=''}
; This is title for the color bar.
;
; @keyword DISCRETE
; Vector which contain color's indexes to trace in a color bar. Therefore
; we obtain a discrete colorbar which contains only the specified colors
; in the order they appear in the vector
;
; @keyword DIVISIONS {default=2}
; The number of divisions to divide the bar into.
; There will be (divisions + 1) annotations.
;
; @keyword FORMAT {default='(F6.2)'}
; The format of the bar annotations.
;
; @keyword CB_LABEL {type=vector}
; A vector to specify sticks values of the color bar. It allows,
; when we use DISCRETE, to have colors that don't increase by
; increments in a regular way.
;
; @keyword MAX {default=NCOLORS - 1}
; The maximum data value for the bar annotation.
;
; @keyword MIN {default=0}
; The minimum data value for the bar annotation.
;
; @keyword NCOLORS {default=!D.N_COLORS}
; This is the number of colors in the color bar.
;
; @keyword NOTITLE
; Force to don't write title even if CB_TITLE is declared.
;
; @keyword POSITION {default=see below}
; A four-element array of normalized coordinates in the same
; form as the POSITION keyword on a plot. Default is
; [0.88, 0.15, 0.95, 0.95] for a vertical bar and
; [0.15, 0.88, 0.95, 0.95] for a horizontal bar.
;
; @keyword PSCOLOR
; This keyword is only applied if the output is being sent to
; a Postscript file. It indicates that the Postscript device
; is configured for color output. If this keyword is set, then
; the annotation is drawn in the color specified by the COLOR
; keyword. If the keyword is not set, the annotation is drawn
; in the color specified by the !P.COLOR system variable
; (usually this will be the color black). In general, this
; gives better looking output on non-color or gray-scale
; printers. If you are not specifically setting the annotation
; color (with the COLOR keyword), it will probably
; be better NOT to set this keyword either, even if you
; are outputting to a color Postscript printer.
;
; @keyword RIGHT
; This puts the labels on the right-hand side of a vertical
; color bar. It applies only to vertical color bars.
;
; @keyword TOP
; This puts the labels on top of the bar rather than under it.
; The keyword only applies if a horizontal color bar is rendered.
;
; @keyword VERTICAL {default=0 -> horizontal color bar}
; Setting this keyword give a vertical color bar.
;
; @keyword _EXTRA
; pass any keyword to colorbar
;
; @restrictions
; The number of colors available on the display device (not the
; Postscript device) is used unless the NCOLORS keyword is used.
;
; @examples
; To display a horizontal color bar above a contour plot, type:
;
;   IDL> LOADCT, 5, NCOLORS=100
;   IDL> CONTOUR, DIST(31,41), POSITION=[0.15, 0.15, 0.95, 0.75], $
;   IDL> C_COLORS=INDGEN(25)*4, NLEVELS=25
;   IDL> COLORBAR, NCOLORS=100
;
; @history
; Written by: David Fanning, 10 JUNE 96.
; 10/27/96: Added the ability to send output to PostScript. DWF
; 11/04/96: Substantially rewritten to go to screen or PostScript
;           file without having to know much about the PostScript device
;           or even what the current graphics device is. DWF
; 01/27/97: Added the RIGHT and TOP keywords. Also modified the
;           way the TITLE keyword works. DWF
; 07/15/97: Fixed a problem some machines have with plots that have
;           no valid data range in them. DWF
; 03/03/98: Add DISCRETE keyword, sebastien masson (smasson\@lodyc.jussieu.fr)
;
; @version
; $Id$
;
;-
PRO colorbar, BOTTOM=bottom, CB_CHARSIZE=cb_charsize $
            , CB_CHARTHICK=cb_charthick $
            , CB_COLOR=cb_color, DIVISIONS=divisions, DISCRETE=discrete $
            , CB_LABEL=cb_label, FORMAT=format, POSITION=position $
            , MAX=max, MIN=min, NCOLORS=ncolors, PSCOLOR=pscolor $
            , CB_TITLE=cb_title, VERTICAL=vertical, TOP=top, RIGHT=right $
            , CB_LOG=CB_log, NOTITLE=notitle, _EXTRA=ex
;
  compile_opt idl2, strictarrsubs
;
; Is the PostScript device selected?
   postScriptDevice = (!D.NAME EQ 'PS')

                                ; Check and define keywords.

   IF N_ELEMENTS(ncolors) EQ 0 THEN ncolors = !D.N_COLORS < 256
   IF N_ELEMENTS(bottom) EQ 0 THEN bottom = 0B
   IF N_ELEMENTS(cb_charsize) EQ 0 THEN cb_charsize = 1.0
   IF N_ELEMENTS(cb_charthick) EQ 0 THEN cb_charthick = 1.0
   IF N_ELEMENTS(format) EQ 0 THEN format = '(F6.2)'
   IF N_ELEMENTS(cb_color) EQ 0 THEN cb_color = ncolors - 1 + bottom
   IF N_ELEMENTS(min) EQ 0 THEN min = 0.0
   IF N_ELEMENTS(max) EQ 0 THEN max = FLOAT(ncolors) - 1
   IF N_ELEMENTS(divisions) EQ 0 THEN divisions = 2
   IF N_ELEMENTS(cb_title) EQ 0 THEN cb_title = ''
   IF N_ELEMENTS(notitle) EQ 1 THEN cb_title = ''
   pscolor = KEYWORD_SET(pscolor)

   IF KEYWORD_SET(vertical) THEN BEGIN
      IF KEYWORD_SET(discrete) THEN begin
         facteur=256/n_elements(discrete)
         discrete=reform(replicate(1,facteur) # discrete,facteur*n_elements(discrete), /overwrite)
         bar = REPLICATE(1B,10) # discrete
      endif else  bar = REPLICATE(1B,10) # BINDGEN(256)
      IF N_ELEMENTS(position) EQ 0 THEN position = [0.88, 0.15, 0.95, 0.95]
   ENDIF ELSE BEGIN
      IF KEYWORD_SET(discrete) THEN begin
         facteur=256/n_elements(discrete)
         discrete=reform(replicate(1,facteur) # discrete,facteur*n_elements(discrete), /overwrite)
         bar =  discrete # REPLICATE(1B,10)
      endif else bar = BINDGEN(256) # REPLICATE(1B, 10)
      IF N_ELEMENTS(position) EQ 0 THEN position = [0.15, 0.88, 0.95, 0.95]
   ENDELSE

; Scale the color bar.
   IF NOT KEYWORD_SET(discrete) THEN $
    bar = BYTSCL(bar, TOP=ncolors-1) + bottom

; Get starting locations in DEVICE coordinates.

   xstart = position[0] * !D.X_VSIZE
   ystart = position[1] * !D.Y_VSIZE

; Get the size of the bar in DEVICE coordinates.

   xsize = (position[2] - position[0]) * !D.X_VSIZE
   ysize = (position[3] - position[1]) * !D.Y_VSIZE

; For PostScript output only, draw the annotation in !P.COLOR
; unless "pscolor" is set. This makes better output on grayscale
; printers.

   IF postScriptDevice AND (pscolor NE 1) THEN BEGIN
      oldcolor = cb_color
      cb_color = !P.COLOR
   ENDIF

; Display the color bar in the window. Sizing is
; different for PostScript and regular display.

   IF postScriptDevice THEN BEGIN

      TV, bar, xstart, ystart, XSIZE=xsize, YSIZE=ysize

   ENDIF ELSE BEGIN

     IF CEIL(xsize) LT 0 OR CEIL(ysize) LT 0 THEN return
      bar = CONGRID(bar, CEIL(xsize), CEIL(ysize), /INTERP)
      TV, bar, xstart, ystart

   ENDELSE

; Annotate the color bar.

   if keyword_set(cb_label) then begin
      divisions = n_elements(cb_label)-1
      for i = 0,divisions DO cb_label = string(cb_label, FORMAT = format)
      format = ''
   ENDIF ELSE cb_label = ''

   IF KEYWORD_SET(vertical) THEN BEGIN

      IF KEYWORD_SET(right) THEN BEGIN

         PLOT, [min,max], [min,max], /NODATA, XTICKS=1, $
          YTICKS=divisions, XSTYLE=1, YSTYLE=9, $
          POSITION=position, COLOR=cb_color, CHARSIZE=cb_charsize, CHARTHICK=cb_charthick $
          , /NOERASE, $
          YTICKFORMAT='(A1)', XTICKFORMAT='(A1)', YTICKLEN=0.1 , $
          YRANGE=[min, max], YTITLE=cb_title

         AXIS, YAXIS=1, YRANGE=[min, max], YTICKFORMAT=format, YTICKS=divisions, $
          YTICKLEN=0.1, YSTYLE=1, COLOR=cb_color, CHARTHICK=cb_charthick $
          , CHARSIZE=cb_charsize, ytickname = cb_label, ylog = cb_log

      ENDIF ELSE BEGIN

         PLOT, [min,max], [min,max], /NODATA, XTICKS=1, $
          YTICKS=divisions, XSTYLE=1, YSTYLE=9, $
          POSITION=position, COLOR=cb_color, CHARSIZE=cb_charsize $
          , CHARTHICK=cb_charthick, /NOERASE, $
          YTICKFORMAT=format, XTICKFORMAT='(A1)', YTICKLEN=0.1 , $
          YRANGE=[min, max], ytickname = cb_label

         AXIS, YAXIS=1, YRANGE=[min, max], YTICKFORMAT='(A1)', YTICKS=divisions, $
          YTICKLEN=0.1, YTITLE=cb_title, YSTYLE=1, COLOR=cb_color $
          , CHARSIZE=cb_charsize, CHARTHICK=cb_charthick, ylog = cb_log

      ENDELSE

   ENDIF ELSE BEGIN

      IF KEYWORD_SET(top) THEN BEGIN

         PLOT, [min,max], [min,max], /NODATA, XTICKS=divisions, $
          YTICKS=1, XSTYLE=9, YSTYLE=1, $
          POSITION=position, COLOR=cb_color, CHARSIZE=cb_charsize $
          , CHARTHICK=cb_charthick, /NOERASE, $
          YTICKFORMAT='(A1)', XTICKFORMAT='(A1)', XTICKLEN=0.1, $
          XRANGE=[min, max], XTITLE=cb_title

         AXIS, XTICKS=divisions, XSTYLE=1, COLOR=cb_color $
          , CHARSIZE=cb_charsize, CHARTHICK=cb_charthick, $
          XTICKFORMAT=format, XTICKLEN=0.1, XRANGE=[min, max], XAXIS=1, xtickname = cb_label, xlog = cb_log

      ENDIF ELSE BEGIN

         PLOT, [min,max], [min,max], /NODATA, XTICKS=divisions, $
          YTICKS=1, XSTYLE=1, YSTYLE=1, $
          POSITION=position, COLOR=cb_color, CHARSIZE=cb_charsize $
          , CHARTHICK=cb_charthick, /NOERASE, $
          YTICKFORMAT='(A1)', XTICKFORMAT=format, XTICKLEN=0.1, $
          XRANGE=[min, max], TITLE=cb_title, xtickname = cb_label, xlog = cb_log

      ENDELSE

   ENDELSE
; Restore color variable if changed for PostScript.

   IF postScriptDevice AND (pscolor NE 1) THEN cb_color = oldcolor

   return
END