;------------------------------------------------------------
;------------------------------------------------------------
;------------------------------------------------------------
;+
;
; @file_comments 
; Choose the way to trace isolines.
;
; @categories
; Graphics
;
; @param LABSTYLE {in}{required}
; Number to which the style of drawing choosen refer to.
;	
; @param LEVEL_Z2D {in}{required}
; Vector containing values of isolignes to be traced.
;
; @param LINESTYLE {out}
; Vector used to define the isocontour's style
;       Comment: remenber:
;		Index	Linestyle	
;		0	Solid	
;		1	Dotted	
;		2	Dashed	
;		3	Dash Dot	
;		4	Dash Dot Dot Dot	
;		5	Long Dashes	
; 
; @param THICK {out}
; Vector defining the thick of the isoline.
;
; @history
; Sebastien Masson (smasson\@lodyc.jussieu.fr)
;
; @version
; $Id$
;
;-
;------------------------------------------------------------
;------------------------------------------------------------
;------------------------------------------------------------
pro style,labstyle,level_z2d,linestyle,thick
;
  compile_opt idl2, strictarrsubs
;
   case labstyle of
      0: begin
;series: Two thin continuous lines, one boldface continuous line
         thick=[1,1,2]
         linestyle=[0]
         return
      end
      1: begin
;series: Before the middle of levels: thin dash. Then thin continuous trait.
; If the middle of the drawing is drawn, it is in boldface continuous trait.
         impair=n_elements(level_z2d)-2*fix(n_elements(level_z2d)/2)
         a=replicate(0,fix(n_elements(level_z2d)/2))
         b=replicate(1,fix(n_elements(level_z2d)/2))
         c=replicate(2,fix(n_elements(level_z2d)/2))         
         if impair then begin
            thick=[b,2,b]
            linestyle=[c,0,a]
         endif else begin
            thick=[0]
            linestyle=[c,a]
         endelse
         return
      end
      2: begin
;series: Before the sill (defined by answering to a question): thin dash.
; Then thin continuous trait. If the sill is drawn, it is in boldface continuous trait.
         seuil=xquestion('Quelle est la limite tirets/trait continu? ','0')
         seuil = float(seuil)
         rien=where(level_z2d lt seuil,n)
         a=replicate(0,n_elements(level_z2d)-n)
         c=replicate(2,n)         
         if seuil eq level_z2d[n] then begin
            thick=[replicate(1,n),2,replicate(1,n_elements(level_z2d)-1-n)]
            linestyle=[c,a]
         endif else begin
            thick=[0]
            linestyle=[c,a]
         endelse
         return
      end
      3: begin
         n = n_elements(level_z2d)
         seuil = level_z2d[1+n/2]

         thick = intarr(n)
         thick[indgen(n/4)*4] = 1
         thick[indgen(n/4)*4+1] = 1
         thick[indgen(n/4)*4+2] = 2
         thick[indgen(n/4)*4+3] = 1

         linestyle = intarr(n)
         linestyle[indgen(n/4)*4] = 3
         linestyle[indgen(n/4)*4+1] = 0
         linestyle[indgen(n/4)*4+2] = 0
         linestyle[indgen(n/4)*4+3] = 0

         labels = intarr(n)
         labels[indgen(n/2)*2] = 1
         labels[n/2] = 0

         return
      end
      4: begin
; Boldface continuous trait.
         seuil = 1.e-6
         thick=replicate(.5,  n_elements(level_z2d))
         linestyle=[0]
         rien=where(abs(level_z2d)/max(abs(level_z2d)) LT seuil)
         if rien[0] NE -1 then thick[rien[0]] = 3
      end
      else: begin
         ras = report('Le numero de labstyle demande n''existe pas')
         stop
      end
   endcase
   return
end