;
; Apply GMT palette into IDL color/intervals system
;
PRO label_gmt, min, max, intervalle, ncoul, ncontour, level_z2d, coul
@common
@com_eg

   IF pal_type NE '2dom' THEN BEGIN 

;  color defined in lec_pal_gmt.pro

      ncontour = ncont_gmt
      level_z2d = levels_gmt
      coul = coul_gmt
      max = max_gmt
      intervalle =  -1

   ENDIF ELSE BEGIN 

      ; grey_shade palette (case 1 in label)
      IF finite(min) EQ 0 THEN read, ' Grey shade needs a min,max :', min, max
      ncontour  = fix((max-min)/intervalle)
      level_z2d = min + intervalle*findgen(Ncontour) 
      max=level_z2d(Ncontour-1)+intervalle

      print, '     Number of contour intervals, plotting min & max ', ncontour, min, max
      print, ' '

      ; color index

      IF idx_pal EQ 0 THEN BEGIN 

         ; build palette
         red = lonarr(99)
         red[*] = 255
         red[50:98] = long((100.-float(grey_shade))/100.*255.)

         IF field.origin EQ 'diff' THEN BEGIN 
      
           ; difference plot : lighter below first negative interval
            red[51:98] = long((100.-float(grey_shade_2))/100.*255.)
            red(1:48) = long((100.-float(grey_shade))/100.*255.)
            red[50] = 255

         ENDIF 

         ; first color=black
         ; last = white
         red = [0, red]
         red[99] = 255
         ; gray scale
         green = red
         blue = red

         tvlct, red, green, blue

      ENDIF  
 
      mid_index = max(where(level_z2d LE fldatt.mid))
      coul = findgen(Ncontour)+49-mid_index +2

   ENDELSE 


END