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From: dlyons@Apple.COM (David A. Lyons)
Newsgroups: comp.sys.apple
Subject: Re: Toolbox Coprocessor?
Message-ID: <38345@apple.Apple.COM>
Date: 5 Feb 90 10:25:07 GMT
References: <3399.25c9904b@vax5.cit.cornell.edu>
Distribution: comp
Organization: Apple Computer Inc, Cupertino, CA
Lines: 30

In article <3399.25c9904b@vax5.cit.cornell.edu> q4kx@vax5.cit.cornell.edu (Joel Sumner) writes:

[How 'bout doing toolbox calls with hardware--asynchronously for the ones
that don't return any information to the caller.]

Getting control of the processor at the right times isn't a problem--
toolbox calls are dispatched through tables of addresses of the functions,
and these can be patched to do whatever you want, including pointing them
at small pieces of code that ask some hardware to do the work.

Letting the application continue before the operation is complete is not
appropriate for most existing toolbox calls, though (it would have to be
synchronous).

Doing stuff like QuickDraw II calls in hardware is far from trivial--
consider all the clipping to regions of any shape (and, if you're a
3rd-party developer, consider Apple's region-related patent).

>Joel Sumner
>Q4KX@cornella.ccs.cornell.edu
>Q4KX@cornella.bitnet
-- 

 --David A. Lyons, Apple Computer, Inc.      |   DAL Systems
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