FUNCTION vu_vox_showheliogrid, F,earthlng, cntr, dvox, obj_val,lngrange,latrange
;+
; NAME:
;	vu_vox_showheliogrid
; PURPOSE:
;	Internal use by vu_vox only
; CATEGORY:
;	Volume Pro board
; INCLUDE:
	@compile_opt.pro			; On error, return to caller
; CALLS:
;	vu_vox_drawlatitude
; MODIFICATION HISTORY:
;	JUL-2002, Cindy Wang  xin_wang02@hotmail.com
;-
FOR I=round(latrange[0]/20),round(latrange[1]/20) DO BEGIN
	lat = I*20
	F = vu_vox_drawhlatitude(F,lat,cntr, dvox, obj_val)
ENDFOR
F = vu_vox_drawhlatitude(F,90,cntr, dvox, obj_val) ;latitude = 90

;mark the earth longitude
FOR I=-2.5,2.5 DO $
 	F = vu_vox_drawhlongitude(F,earthlng+I,cntr,dvox,obj_val)

FOR J=round(lngrange[0]/20),round(lngrange[1]/20) DO BEGIN
 	lng = J*20+earthlng
 	F = vu_vox_drawhlongitude(F,lng,cntr, dvox, obj_val)
ENDFOR

RETURN, F  &  END