PRO normrot,img,p,az,el,zang,yang,cam,filt,lbsang,date

primemer=[147.32,147.32]
PRINT,'zang=',zang
IF ((zang GT -90) AND (zang LT 90)) AND (MAX(az) GT 180) $
	THEN az(WHERE(az GE 180))=az(WHERE(az GE 180))-360
readnorm,cam,filt,map,maz,mza
mel=90-mza
normimg=FLTARR(256,256)

position,cam,filt,maz,mza,cl,rw
cl=cl/2. & rw=rw/2.
normimg(cl,rw)=map
normimg=MEDIAN(normimg,3)
TVSCL,normimg>0.8,1
IF lbsang EQ 0 THEN $
    XYOUTS,384,490,ALIGNMENT=0.5,"Normalizing map",/DEVICE ELSE $
    XYOUTS,384,490,ALIGNMENT=0.5,"Before rotation",/DEVICE
TVSCL,img>(0.8*MAX(img)),2
XYOUTS,128,234,"Dark-corrected image",/DEVICE,ALIGNMENT=0.5

IF lbsang EQ 0 THEN BEGIN
    flatimg=normimg*img 
    wwww=WHERE(flatimg)
    sdf=stdev(flatimg(wwww),mf)
    PRINT,mf,100*sdf/mf $
	 ,FORMAT='("Mean = ",F7.1," DN; s.d. = ",F4.1,"% of mean")'
    ENDIF ELSE BEGIN
    ; Instead of rotating about the zenith, try rotating about the center
    ; of the LBS image
    ;w=MAX(el,loc)
    ;one2two,loc,img,xz,yz
    ;normimg=rot(normimg,+147.40-zang,1.,xz,yz,/pivot)
    WINDOW,2,XSIZE=256,YSIZE=256
    meancent,normimg,xc,yc
    WDELETE,2
    normimg=rot(normimg,+primemer(cam)-zang,1.,ROUND(xc),ROUND(yc),/pivot)
    TVSCL,normimg>0.8,3
    XYOUTS,384,234,ALIGNMENT=0.5,"After rotation",/DEVICE
    pt=WHERE(normimg)
    ;polrec3d,1.,90-el,(90-az),x,y,z,/DEGREES
    polrec3d,1.,90-el,-az,x,y,z,/DEGREES
    ;rot_3d,3,x,y,z,90-zang,x0,y0,z0,/DEGREES
    rot_3d,3,x,y,z,zang,x0,y0,z0,/DEGREES
    rot_3d,2,x0,y0,z0,-yang,x1,y1,z1,/DEGREES
    ;rot_3d,3,x1,y1,z1,zang-90,x2,y2,z2,/DEGREES
    rot_3d,3,x1,y1,z1,-zang,x2,y2,z2,/DEGREES
    x='' & x1='' & y='' & y1='' & z='' & z1=''

    recpol3d,x2,y2,z2,r,za2,ang,/DEGREES
    ;az2=90-ang & el2=90-za2
    az2=-ang & el2=90-za2
    wn=WHERE(az2 LT 0)
    az2(wn)=az2(wn)+360.
    IF ((zang GT -90) AND (zang LT 90))$
	THEN az2(WHERE(az2 GE 180))=az2(WHERE(az2 GE 180))-360
    x2=0 & y2=0 & z2=0

    TRIANGULATE,az2(pt),el2(pt),triangles

    ti2=TRIGRID(az2(pt),el2(pt),normimg(pt),triangles,[.25,.5],$
	[MIN(az2(pt)),MIN(el2(pt)),MAX(az2(pt)),MAX(el2(pt))])

    triangles=0

    lbs=WHERE(img GT MAX(img)/1.33)
    rni=FLTARR(256,256)
    azl=(az(lbs)-MIN(az2(pt)))/0.25
    ell=(el(lbs)-MIN(el2(pt)))/0.5

    rni(lbs)=INTERPOLATE(ti2,azl,ell)
    flatimg=rni*img
    ENDELSE

; put a frame around the flattened image for context
fimg=flatimg
mp=MAX(flatimg)
fimg(0,*)=mp
fimg(255,*)=mp
fimg(*,0)=mp
fimg(*,255)=mp
TVSCL,fimg>(0.8*mean(flatimg))
IF lbsang NE 0 THEN TVSCL,rni,0
TVSCL,normimg,1
TVSCL,img>(0.8*MAX(img)),3
PRINT,'Would you like to save this image ([Y]/N)'
ans=''
READ,ans
IF STRUPCASE(ans) NE 'N' THEN BEGIN
      IF lbsang LT 0 THEN sign='-' ELSE sign='+'
      IF zang LT 0 THEN ext=FIX(ROUND(360+zang)) ELSE ext=FIX(ROUND(zang))

      fname=STRING(date,cam,filt,sign,ABS(lbsang),ext,$
	FORM='("/jasper/cnsr3_data1/flat/fn",I2.2,2I1,A,I2.2,".",I3.3)')
      OPENW,u,fname,/GET_LUN
      WRITEU,u,FIX(flatimg)
      CLOSE,u & FREE_LUN,u
ENDIF
RETURN
END