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From: 6500boo@ucsbuxa.ucsb.edu (William Bushing)
Newsgroups: comp.lang.pascal
Subject: Storing screen image for quick display
Message-ID: <8416@hub.ucsb.edu>
Date: 22 Jan 91 01:48:09 GMT
Sender: news@hub.ucsb.edu
Distribution: comp
Lines: 28

I'm not the World's Greatest Turbo Pascal programmer, but once
I get a sense of direction I can muddle through.

I wrote software to read a data file and display 512 x 512
images in 800 x 600 sVGA mode. After displaying the image I
want to do things like thresholding, creating binary images,
applying false color palettes, etc., without destroying the
original image. In other words I want to temporarily apply
thresholding, etc., then be able to QUICKLY redisplay the 
original screen image.

I tried using arrays to store the pixel values in a [512,512]
array (too large for TP 5.5) and a series of four [512,128]
arrays. No luck. What data structure should I use to store the
image and then quickly recall it? If it involves pointers, I
don't feel comfortable with them. Can I use my computer's RAM
to store the pixel values in a contiguous set of memory addresses
and then retrieve the values?

All I need is the proper direction to turn, not complete code
(although a basic idea might help). Many thanks in advance
for any help.

^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
William W. (Boo) Bushing  |  "Life is too important to be
6500boo@ucsbuxa.bitnet    |       taken seriously"
6500boo@ucsbuxa.ucsb.edu  |            - Einstein
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