pro map_continents,  $
	mlinestyle = mlinestyle, color = color, t3d=t3d, $
	mlinethick = mlinethick, USA = usa, CONTINENTS = cont

if (!x.type NE 2) THEN message,'Map transform not established.'
latmin = !map.out(4)
latmax = !map.out(5)
lonmin = !map.out(2)
lonmax = !map.out(3)

if N_Elements(mlinestyle) EQ 0 THEN mlinestyle=0
if N_Elements(mlinethick) EQ 0 THEN mlinethick=1
if n_elements(t3d) le 0 then t3d = 0
if n_elements(color) le 0 then begin	;Default color?
	if (!d.flags and 512) ne 0 then color = 0 else color = !d.n_colors-1
	endif

maxlat=0. & minlat=0. & maxlon=0. & minlon=0.

openr, lun, /get, FILEPATH('supmap.dat',subdir = "maps"),/xdr,/stream
npts = 0L
; 	cont us_only  both
fbyte = [ 0, 71612L, 165096L]
nsegs = [ 283, 325, 594 ]


if n_elements(usa) eq 0 then usa = 0
if n_elements(cont) eq 0 then cont = 0

ij = 0			;Default = continents only
if usa ne 0 then begin
	if cont then ij = 2 else ij = 1
	endif
point_lun, lun, fbyte(ij)

for i=1,nsegs(ij) do begin
	READU, lun, npts,maxlat,minlat,maxlon,minlon
	npts = npts / 2		;# of points
	xy = fltarr(2,npts)
	READU, lun, xy
	if (maxlat lt latmin) or (minlat gt latmax) then goto,skipit
	
	if (maxlon lt lonmin) or (minlon gt lonmax) then BEGIN
          if (lonmax gt 180 and maxlon + 360 ge lonmin) then goto,goon
          if ( lonmin lt -180 and minlon -360 le lonmax) then goto,goon
          goto, skipit
        END
     

goon:	plots, xy(1,*), xy(0,*), NOCLIP=0, t3d=t3d, $
		THICK=mlinethick,linestyle=mlinestyle, color = color

skipit:

       	endfor
FREE_LUN, lun
end