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From: mdavis@pro-sol.cts.com (Morgan Davis)
Newsgroups: comp.sys.mac.programmer
Subject: Re: Animation
Message-ID: <7494@crash.cts.com>
Date: 9 Feb 91 20:39:35 GMT
Sender: root@crash.cts.com
Lines: 40

In-Reply-To: message from dweisman@umiami.ir.miami.edu
} > 	tmp := TickCount;
} > 	while tmp=Tickcount do { nothing } ;
} > 	
} > 	CopyBits(.....)
}
} This is fine except for a minor detail. As it says in IM Vol. I...
} 
} [quote removed]
}
} So instead say:
} 
} 	tmp:=TickCount;
} 	repeat until TickCount>=(tmp+1);
} 
} 	CopyBits.....
}
} ==Dan

Your method, derived from what you understood about TickCount from Inside
Mac, is almost as safe as the first one, but certainly not any better.  While
the first example would loop until Ticks changed, your example would loop
until Ticks increased by some amount.  In reality, they're identical in
function, only your method would not work if Ticks had somehow managed to
decrease in value.

In either case, I think it is important to realize that both methods are
equally acceptable for this situation.  Where I think you misinterpreted
Inside Mac is when you have a scenario such as this:

        tmp := TickCount;
        repeat until TickCount = (tmp + N);

The problem here is that you're waiting for TickCount to equal a certain
constant value *OTHER THAN ITS OLD VALUE*.  This isn't safe.  It is important
to understand the difference.

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