Path: utzoo!utgpu!attcan!uunet!mcvax!unido!laura!jf
From: jf@laura.UUCP (Jan Hinrich Fessel)
Newsgroups: comp.sys.atari.st
Subject: Re: Questions about ST Video Ram
Summary: No 32k for the shifter
Message-ID: <529@laura.UUCP>
Date: 3 Aug 88 15:45:21 GMT
References: <535@skywest.UUCP>
Reply-To: jf@laura.UUCP (Jan Hinrich Fessel)
Organization: University of Dortmund, W-Germany
Lines: 22

In article <535@skywest.UUCP> brenes@skywest.UUCP (Erasmo Brenes) writes:
>Hello, this is a question to the ST graphic 'gurus':
>question is: If the Shifter expects the video ram to start at 32K boundaries,
>then how do I get MWC, or any C program to allocate a 32Kb buffer starting in
>a 32Kb boundary in an efficient manner?  An initial thought was to use Malloc()
>to allocate 64Kb and then only use the 32Kb which start in a 32Kb boundary,
>but this method is too wasteful. There's got to be a better way, isn't there?
>
Me no graphic-guru, but as far as I know the buffer has to be aligned on a
512 byte boundary, so Malloc() is wasting only up to 511 bytes.
Hope thats correct, i haven't tried it yet:-)

Jan-Hinrich

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