;+
; NAME:
;     SFD_CDS
; PURPOSE:
;     overlay CDS field of view on the most recent SFD
; CATEGORY:
; CALLING SEQUENCE:
;     sfd_cds, cds_cen, cds_fov
;     sfd_cds, [0,0], [240,240] would be a standard FOV at disk center
;     sfd_cds, cds_cen, cds_fov, /notv
; INPUTS:
;     CDS parameters (see 
;       http://sohodb.nascom.nasa.gov/synoptic/.targets/soho_today.html)
;     notv, when set, lets you put another box on the same image
;     defaults to Sun center and an SXT 2x2 FOV
; OPTIONAL (KEYWORD) INPUT PARAMETERS:
; OUTPUTS:
; COMMON BLOCKS:
; SIDE EFFECTS:
; RESTRICTIONS:
; MODIFICATION HISTORY:
;     HSH, written 24-Apr-97
;-

pro sfd_cds, cds_cen, cds_fov, qstop=qstop, notv = notv
lastsfd,index,data,/notv
if n_elements(cds_fov) eq 0 then cds_fov = [314,314]/2
if n_elements(cds_cen) eq 0 then cds_cen = [0,0]
if keyword_set(notv) then begin
  lastsfd,index,data,/notv
endif else lastsfd,index,data
cds_cen = conv_a2p(cds_cen,index)/2
if keyword_set(notv) eq 0 then begin
  fact = gt_pix_size(gt_res(index))
endif else fact = 4.92
cds_fov = cds_fov/fact
x0 = cds_cen(0)-cds_fov(0)
x1 = cds_cen(0)+cds_fov(0)
y0 = cds_cen(1)-cds_fov(1)
y1 = cds_cen(1)+cds_fov(1)
draw_boxcorn,x0,y0,x1,y1
if keyword_set(qstop) then stop
end