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From: jcav@quads.uchicago.edu (john  cavallino)
Newsgroups: comp.sys.mac.programmer
Subject: Re: Source code request
Message-ID: <1991Apr19.184613.18406@midway.uchicago.edu>
Date: 19 Apr 91 18:46:13 GMT
References: <4c3JO2600WBLE0ZlJU@andrew.cmu.edu> <1608@babcock.cerc.wvu.wvnet.edu> <23407@unix.SRI.COM>
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In article <23407@unix.SRI.COM> mxmora@unix.sri.com (Matt Mora) writes:
>In article <1608@babcock.cerc.wvu.wvnet.edu> un020070@vaxa.wvnet.edu writes:
>>    VAR
>>       oldPort   : GrafPtr;     {saved port}
>>       offScreen : GrafPort;    {our offscreen bitmap}
>>       ovalRect  : Rect;        {used for example drawing}
>>
>>the offscreen port and bitmap can be allocated with the following statements:
>>    
>>    GetPort(oldPort);
>>    OpenPort(@offScreen);
>              ^
>          IS THAT RIGHT?
>
>I don't think you need the @ sign here. 
>Or at the other SetPort(@Offscreen);

Actually, it is correct, but the style is somewhat yecchy.

OpenPort takes a GrafPtr, the variable "offscreen" is a GrafPort, the "@"
operator takes the address of something, so @offscreen give you a GrafPtr.

It would be easier to read if there were an explicit variable of type GrafPtr.



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