;------------------------------------------------------------
;------------------------------------------------------------
;------------------------------------------------------------
;+
; NAME:axis4pltz
;
; PURPOSE:compute the mask and the axis for a vertical section
;
; CATEGORY:
;
; CALLING SEQUENCE:
; 
; INPUTS:mask: 3d mask
;        glam, gphi: 2d longitudes and latitudes
;        z:1d depth
;
; KEYWORD PARAMETERS:
;        XXAXIS to get the xaxis we need to use in pltbase
;        ZZAXIS to get the yaxis we need to use in pltbase
;
;        Others: see pltz 
;
; OUTPUTS:
;
; COMMON BLOCKS:
;
; SIDE EFFECTS:
;
; RESTRICTIONS:
;
; EXAMPLE:
;
; MODIFICATION HISTORY:Sebastien Masson (smasson@lodyc.jussieu.fr)
;                      June 24, 2002
;-
;------------------------------------------------------------
;------------------------------------------------------------
;------------------------------------------------------------

PRO axis4pltz, type, mask, glam, gphi, z, XXAXIS = xxaxis, ZZAXIS = zzaxis, SIN = sin, ZRATIO = zratio, ZOOM = zoom, PROFMAX = profmax, PROFMIN = profmin, _extra = ex
;
; include common
;
  compile_opt idl2, strictarrsubs
;
@cm_4mesh
  IF NOT keyword_set(key_forgetold) THEN BEGIN
@updatekwd
  ENDIF
  
;--------------------------------------------------------------------
; define the mask used for this section
;--------------------------------------------------------------------
  if mask[0] NE -1 AND (size(mask))[0] NE 2 then begin
    if type EQ 'xz' then mask = total(mask, 2) < 1 $
    ELSE mask = total(mask, 1) < 1
  endif
;--------------------------------------------------------------------
; define xxaxis and yyaxis the axis used for this section
;--------------------------------------------------------------------
  nx = (size(glam))[1]
  CASE (size(gphi))[0] OF
    1:ny = (size(gphi))[1]
    2:ny = (size(gphi))[2]
  ENDCASE
  CASE (size(z))[0] OF
    1:nz = (size(z))[1]
    2:nz = (size(z))[2]
  ENDCASE
;
  if type eq 'yz' then BEGIN 
    IF (size(gphi))[0] EQ 1 then xxaxis = gphi ELSE BEGIN 
      IF keyword_set(key_irregular) THEN BEGIN 
        cln = (where(gphi EQ max(gphi)))[0]
        xxaxis = reform(gphi[cln MOD nx, *])
      ENDIF ELSE xxaxis = reform(gphi[0, *])
    ENDELSE
    if keyword_set(sin) then xxaxis = sin(!pi/180.*xxaxis)
    if (size(z))[0] EQ 1 THEN zzaxis = z ELSE zzaxis = z
  ENDIF ELSE BEGIN
    xxaxis = glam[*, 0]
    if (size(z))[0] EQ 1 then zzaxis = z ELSE zzaxis = z
  ENDELSE 
;----------------------------------------------------------
; on projette l''axe z dans [0,1]
;----------------------------------------------------------
  if not keyword_set(zratio) then zratio = 2./3
  if zoom ge profmax then zratio = 1.
  if zoom LT profmax then begin
    mp = projsegment([profmin, zoom], [0, zratio], /mp)
    zzaxis[where(zzaxis LE zoom)] = mp[0]*zzaxis[where(zzaxis LE zoom)]+mp[1]
    mp = projsegment([zoom, profmax], [zratio, 1], /mp)
    zzaxis[where(zzaxis GE zoom)] = mp[0]*zzaxis[where(zzaxis GE zoom)]+mp[1]
  ENDIF ELSE BEGIN
    mp = projsegment([profmin, profmax], [0, 1], /mp)
    zzaxis = mp[0]*zzaxis+mp[1]
  ENDELSE

; to draw from bottom to top (avoid using cell_fill)
  CASE size(zzaxis, /n_dimensions) OF
    1:zzaxis = reverse(-zzaxis) 
    2:zzaxis = reverse(-zzaxis, 2) 
  ENDCASE
  if mask[0] NE -1 then mask = reverse(mask, 2)

  return
end