;+ ; NAME: ; OPLOTIMAGE ; ; AUTHOR: ; Craig B. Markwardt, NASA/GSFC Code 662, Greenbelt, MD 20770 ; craigm@lheamail.gsfc.nasa.gov ; ; PURPOSE: ; Overlays an image on an existing plot. ; ; CALLING SEQUENCE: ; OPLOTIMAGE, img ; ; DESCRIPTION: ; ; OPLOTIMAGE overlays an image on an already-existing set of plot ; axes. It should not matter what plot elements have already be ; displayed, but at least one command is needed to set up the plot ; axes. ; ; Only the IMGXRANGE and IMGYRANGE keywords, specifying the extent ; of the image, can be given in a call to OPLOTIMAGE. ; ; See PLOTIMAGE for more detailed information. ; ; INPUTS: ; ; IMG - A byte array to be displayed. An image declared as ; ARRAY(M,N) will be M pixels in the x-direction and N pixels ; in the y-direction. The image is resampled via ; interpolation to fill the desired display region. ; ; OPTIONAL INPUTS: ; NONE ; ; INPUT KEYWORD PARAMETERS: ; ; IMGXRANGE, IMGYRANGE - Each is a two component vector that ; describes the X and Y position of the first ; and last pixels. ; Default: the size of the image in pixels ; ; OUTPUTS: ; NONE ; ; PROCEDURE: ; ; EXAMPLE: ; ; This example first constructs an image whose values are found by ; z(x,y) = cos(x) * sin(y) ; and x and y are in the range [-2,2] and [4,8], respectively. ; The image is then plotted in the range [-10, 10] in both x and ; y directions. ; ; x = findgen(20)/5. - 2. ; y = findgen(20)/5. + 4. ; zz = cos(x) # sin(y) ; imgxrange = [min(x), max(x)] ; imgyrange = [min(y), max(y)] ; xr=[-10.,10] ; yr=[-10.,10] ; plotimage, bytscl(zz), imgxrange=imgxrange, imgyrange=imgyrange ; ; Now for the overlay. A new image is created in the ranges between ; -10 and 0: ; z(x,y) = x y ; ; x = findgen(20)/2 - 10. ; y = findgen(20)/2 - 10. ; imgxrange = [min(x), max(x)] ; imgyrange = [min(y), max(y)] ; zz = x # y ; oplotimage, bytscl(zz), imgxrange=imgxrange, imgyrange=imgyrange ; ; SEE ALSO: ; ; PLOTIMAGE, BYTSCL ; ; EXTERNAL SUBROUTINES: ; ; SUBCELL, DEFSUBCELL, TVIMAGE ; ; MODIFICATION HISTORY: ; Written, CM, 1997 ; Removed BYTE requirement, added ON_ERROR, CM 19 Apr 2000 ; Added copyright notice, CM 25 Mar 2001 ; ; $Id: oplotimage.pro,v 1.2 2001/03/25 18:10:44 craigm Exp $ ; ;- ; Copyright (C) 1997-2001, Craig Markwardt ; This software is provided as is without any warranty whatsoever. ; Permission to use, copy, modify, and distribute modified or ; unmodified copies is granted, provided this copyright and disclaimer ; are included unchanged. ;-