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From: russotto@eng.umd.edu (Matthew T. Russotto)
Newsgroups: comp.sys.mac.programmer
Subject: Re: Advice on icon animation wanted
Message-ID: <1990Dec21.191852.2000@eng.umd.edu>
Date: 21 Dec 90 19:18:52 GMT
References: <1116@babcock.cerc.wvu.wvnet.edu> <1990Dec18.205338.6800@svc.portal.com> <11592@goofy.Apple.COM>
Sender: news@eng.umd.edu (C-News)
Organization: College of Engineering, Maryversity of Uniland, College Park
Lines: 42

In article <11592@goofy.Apple.COM> rmh@apple.com (Rick Holzgrafe) writes:
>In article <1990Dec18.205338.6800@svc.portal.com> daven@svc.portal.com 
>writes:
>> Using a VBL task would probably produce the smoothest animation. However,
>> there is an issue here I've always wondered about. With the non-color
>> Mac's the VBL task was tied to the vertical blanking of the B&W monitor.
>> With the color Mac's there is no gaurantee that this is so. I believe the
>> Apple 13" color monitor refreshes it's screen at a faster rate than the 
>60Hz
>> rate of the VBL task queue. So, could animation by means of a VBL task 
>could
>> cause some flicker on a color monitor?
>
[SlotVInstall info]

>"So how do I find out what slot the monitor is in?" Here I gotta go out on 
>a limb - I haven't tried this stuff, I've just pawed through Inside Mac 
>Vol. V. If I understand what I've read correctly, you use the routines in 
>Chapter 5 "Graphics Devices" to learn about each of the display devices 
>that are available. The GDevice record for each will give you the refnum 
>of the driver for the monitor. Now go to Chapter 23 "The Device Manager" 
>and use the refnum to get the AuxDCE record for the driver; this will give 
>you the slot number.
>
>Hope this helps (and I hope it's correct...)

Sounds correct to me-- here's the code I use.

gd = GetMainDevice();  /* or get a different device if you like */
SlotVInstall(taskptr, (*GetADCtlEntry((*gd)->gdRefNum))->dCtlSlot);

AuxDCEHandle GetADCtlEntry(refnum)
unsigned long refnum;
{
	return *(*((AuxDCEHandle **)0x11c) + (refnum ^ 0xFFFFFFFF));
}

(0x11c is the unit table base)

--
Matthew T. Russotto	russotto@eng.umd.edu	russotto@wam.umd.edu
     .sig under construction, like the rest of this campus.