Pro Rdpixk, Image,X0, Y0,xo,yo,ifact,icount,img,xp,yp ;Read the value of the pixel of
			;the ORIGINAL image that happens to be under the 
 			;cursor.
			;Display x,y and the pixel value under the cursor
	                ;of a ZOOM-ed image.  Write the coordinates to a file
	                ;as well as to the screen.
; NAME:
;	RDPIXk
; PURPOSE:
;	Display the X, Y, and pixel value of the cursor on a ZOOM-ed image,
;	as well as the values of the corresponding spectral images.
;	write the coordinates to a file.
; CATEGORY:
;	Image display
; CALLING SEQUENCE: (NOTE:  this procedure is called only from within
;	                    specdisplay.)
;	RDPIXK, Image [, X0, Y0],xo,yo,ifact,icount,img
; INPUTS:
;	Image = Zoomed image.   
;	xo,yo = location of lower left corner of zoomed image in the 
;	  pixel-space of the original image.
;	ifact = the scaling factor by which the image has been zoomed.
;	icount = a book-keeping term which, if 0, signifies that this is 
;	  the first time rdpix2 has been called during a particular session
;	  of zoom2.
;	img = the original, NON-scaled-for-display image.
; OPTIONAL INPUT PARAMETERS:
;	X0, Y0 = Optional location of lower left corner of image area on
;	  screen.
; OUTPUTS:
;	None. 
; COMMON BLOCKS:
;	None.
; SIDE EFFECTS:
;	The X, Y and value of pixel under the cursor are constantly 
;	displayed.  Cursor values indicate values of the original image.
;	The "Scaled value" idicates the value scaled to an integer from
;	0 to 32000, such as would be done to the image for processing of the
;	image with SRS.
;	Pressing left or center mouse button, makes a new line of output,
;		saving the old to both the screen and a file.
;	Pressing right mouse button exits the procedure, giving control
;	        back to zoom2.
; RESTRICTIONS:
;	None.
; PROCEDURE:
;	Straightforward.
; MODIFICATION HISTORY:
;	J.Ingalls 1991
;	K. Tsetsenekos 1997 - altered to allow analysis of spectral images
;-
;+
;
common block1,redweight,blueweight,greenweight,red1,blue1,green1
rw=redweight & bw=blueweight & gw=greenweight

print,'RDPIX ENGAGED'
print,'Please Wait'
print,' '
;-
;    first determine the scaled image:
;
min_img=min(img)
max_img=max(img)-min_img
newimage=img-min_img
newimage=(32000/max_img)*newimage
inewimage=fix(newimage)
;
;if (icount eq 0)then begin
;openw,unit,'stars.ppos',/get_lun
;endif else begin
openw,unit,'stars.ppos',/append,/get_lun
;endelse
print,'Press left mouse button to pan '
print,'... center mouse button for new output line.'
print,'... right mouse button to exit.'
print,' '
s = size(image)
if s(0) ne 2 then begin
	print,'Rdpix -- Image parameter not 2d'
	return
	end
s(1) = s(1)-1		;To n-1
s(2) = s(2)-1
!err=0
x1=-1 & y1=-1		;Previous values
if n_elements(x0) le 0 then x0 = 0
if n_elements(y0) le 0 then y0 = 0
if s(s(0)+1) ge 4 then form = 'F' else form = 'I'
cr = string("15b)
;form="($,'x=',i4,', y=',i4,', value=',f9.3,', scaled value=',i5,a,a)"
;form="($,'x=',i4,', y=',i4,', value=',e9.3,a,a)"
;form="($,'x=',i4,', y=',i4,', red value=',i4,', red weight=',i2,', green value=',i4,', green weight=',i2,', blue value=',i4,', blue weight=',i2,a,a)"
form="($,'x=',i4,', y=',i4,', red weight=',i2,', green weight=',i2,', blue weight=',i2,a,a)"
form2="(2i6)"
new_wind=-1
old_wind=!d.window
ierase = 0		;erase plot window flag
while !err ne 4 do begin
	tvrdc,x,y,2,/dev
	if (!err eq 2) then begin	;New line?
; since tvrdc sees pixels as being of only one size, the x and y
; coordinates that it sees must be divided by ifact, the zooming factor,
; to get a coordinate in the pixel space of the original image.  
; This must occur in conjunction with the addition of the
; vector (xo,yo) to the zoomed image, which tvrdc sees as beginning with
; pixel (0,0).
           printf,unit,form=form2,x/ifact+xo,y/ifact+yo
	   print,form="($,a)",string("12b)
	   if new_wind lt 0 then begin	;Make new window?
	      window,/free,xsiz=512,ysiz=512
	      new_wind=!d.window
	   endif else begin
	      wset,new_wind
	      if ierase then erase		;Erase it?
	      ierase = 0
	   endelse
	   cart_conv,0,0,70,x,y,spectrum,waves
	   plot,waves,spectrum
	   wset,old_wind
	   while (!err ne 0) do begin wait,.1 & tvrdc,x,y,0,/dev & end
	endif
	if (!err eq 1) then begin
	    b=' '
	    print,string(format='(a51)',b)
	    print,'Click on point you want to pan to.'
	    cursor,xp,yp,3,/dev
	    xp=xp/ifact+xo
	    yp=yp/ifact+yo
	    goto,done
	endif
	x = x-x0 & y = y - y0
	if !order ne 0 then yy = (s(2) > !d.y_vsize) - 1 - y $
		else yy = y
;	if (x le s(1)) and (yy le s(2))  and (x ge 0) and $
;	  (y ge 0) then $
	ix=fix(x/ifact)+xo
	iy=fix(y/ifact)+yo
;	iy=iy < 527
;	ix=ix < 527
;	red=red1(ix,iy) & blue=blue1(ix,iy) & green=green1(ix,iy)
;        print,form=form,ix,iy,red,rw,green,gw,blue,bw,cr,string(15b)
        print,form=form,ix,iy,rw,gw,bw,cr,string(15b)
;        print,form=form,ix,iy,img(ix,iy),cr,string(15b)
;        print,x,y,img(ix,iy),cr,string(15b)
	x1 = x & y1=y
endwhile
	print,form="(/)"
	print,'RDPIX MODE DISENGAGED'
	if (new_wind ge 0) then wdelete,new_wind
	print,form="(/)"
done:	free_lun,unit
end