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From: dg@sundog.caltech.edu (DALE GARY)
Newsgroups: comp.sys.amiga.tech
Subject: Zooming a bitmap
Message-ID: <1990Oct25.153123.25376@nntp-server.caltech.edu>
Date: 25 Oct 90 14:19:07 GMT
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Organization: California Institute of Technology
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My associate left a message on this subject on comp.sys.amiga, but this
is probably a better group for this question.  We are trying to write a
program that includes a zoom feature for taking part of a bitmap and
displaying an enlarged version in another window.  The LENS and ZOOM
programs do this very well, so I would either like to find a version of
those that work on a custom screen, or else find out how they do it
so we can write our own routine.  

I think the VLT docs indicate that it is possible to use LENS on VLT's
screen, but I have not found that program (not on the FISH disks,
anyway).  I assume this also requires using screenshare.library. 

As far as writing our own verion, when I think about how a zoom
algorithm would work, I'm sure my version will take forever to update
(sort of like DPaintIII's zoom feature :-)), so there must be a "trick"
to it.  Any ideas out there? Thanks. 

Dale Gary