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Re: overplotting lines over images [message #7497 is a reply to message #7401]

Thu, 14 November 1996 00:00

David Foster
Messages: 341
Registered: January 1996

Senior Member

Mirko Vukovic wrote:
>
> I want to overplot lines over an image. The way I'd like it is to OR
> it, in the sense that the line is dark over light parts and light over
> dark parts. Thought that I've seen that written or mentioned somewhere,
> but cannot find anything in the manual.
>

You have to change the graphics mode to XOR mode, draw stuff, and
then restore the old graphics mode:

wset, my_window
color = !d.table_size - 1
device, get_graphics = oldg, set_graphics = 6
plots, [x1,x2], [y1,y2], /noclip, /device, color = color
device, set_graphics = oldg

You can later "erase" the line by doing the same commands again.

Hope this helps.
--

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~
David S. Foster Univ. of California, San Diego
Programmer/Analyst Brain Image Analysis Laboratory
foster@bial1.ucsd.edu Department of Psychiatry
(619) 622-5892 8950 Via La Jolla Drive, Suite 2200
La Jolla, CA 92037
[ UCSD Mail Code 0949 ]
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~

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[Message index]

		overplotting lines over images By: Mirko Vukovic on Wed, 13 November 1996 00:00
		Re: overplotting lines over images By: Mirko Vukovic on Thu, 14 November 1996 00:00
		Re: overplotting lines over images By: Robert Moss on Thu, 14 November 1996 00:00
		Re: overplotting lines over images By: David Foster on Thu, 14 November 1996 00:00
		Re: overplotting lines over images By: Christian Soeller on Thu, 14 November 1996 00:00

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