[comp.sys.mac] Finder 6.0 in "Scourge of the Killer Icons"

ephraim@think.COM (ephraim vishniac) (02/01/88)

Running Finder 6.0, System 4.2 on a Mac II, I found this catastrophic
Finder bug over the weekend:

If the icon mask (second half of the ICN# resource) for a file is
blank (all zeroes), attempting to drag the file in an icon view kills
the Finder.  Sometimes it bombs, sometimes it scrambles the screen,
sometimes it just freezes solid - no mouse, no keyboard, no debugger.

To fix the problem, use ResEdit to open the file which provides the
brain-damaged icon.  Open the ICN# resources, open the offending ICN#,
and draw a mask.  Close and save the file.

The defective ICN# is also in your desktop file, so you can either
	(a) delete the desktop file while you're in ResEdit;
	(b) edit the desktop copy of the ICN# in question in ResEdit; or
	(c) hold the command and option keys while exiting ResEdit, so that
	    the Finder will offer to rebuild the desktop.

The program in which I found the problem is Mandelbrot Microscope, a
color Mandelbrot set plotter.  Only the saved set icon has this
problem; the application icon and saved color table icons are OK.


Ephraim Vishniac					  ephraim@think.com
Thinking Machines Corporation / 245 First Street / Cambridge, MA 02142-1214

francine@cooper.cooper.EDU (Francine Ponenti ) (02/05/88)

in article <16005@think.UUCP>, ephraim@think.COM (ephraim vishniac) says:
> 
> Running Finder 6.0, System 4.2 on a Mac II, I found this catastrophic
> Finder bug over the weekend:
> 
> If the icon mask (second half of the ICN# resource) for a file is
> blank (all zeroes), attempting to drag the file in an icon view kills
> the Finder.  Sometimes it bombs, sometimes it scrambles the screen,
> sometimes it just freezes solid - no mouse, no keyboard, no debugger.

This appears to be a very severe result of a bug that was introduced into
Finder 6.0.  The Finder appears to no longer handles ICN#'s correctly.
For example, click once upon an application such as Lightspeed C that has
an icon that changes when you click on it.  (LC's icon changes from a
starfield to a box with a C inside of it)  Notice that the icon does not
correctly change.  (into the C in this case)  I believe that instead of
overlaying the mask with the original icon to get the new icon, the mask
is being drawn by itself.  This may be a change that Apple made to make
the use of the ICN# masks easier, so that instead of drawing an icon and
masking changes to it, you simply draw two seperate icons.

Francine

isle@eleazar.Dartmouth.EDU (Ken Hancock) (02/08/88)

In article <1193@cooper.cooper.EDU> francine@cooper.cooper.EDU (Francine Ponenti ) writes:
>in article <16005@think.UUCP>, ephraim@think.COM (ephraim vishniac) says:
>> If the icon mask (second half of the ICN# resource) for a file is
>> blank (all zeroes), attempting to drag the file in an icon view kills
>> the Finder.  Sometimes it bombs, sometimes it scrambles the screen,
>> sometimes it just freezes solid - no mouse, no keyboard, no debugger.
>
>This appears to be a very severe result of a bug that was introduced into
>Finder 6.0.  The Finder appears to no longer handles ICN#'s correctly.

Apple already stated that programs such as LSC, Red Ryder, etc. are doing
no-no's when they change the masks.  The problem, I believe, started
with how multifinder handles the mask when an application is launched.

As for the bombing, freezing, screen frenzy, that sounds serious enough
that regardless of what the application ICN# does in it's mask that
shouldn't happen.

Ken


-- 
Ken Hancock      UUCP: isle@eleazar.dartmouth.edu
               BITNET: isle@eleazar.dartmouth.edu

DISCLAIMER: If people weren't so sue-happy, I wouldn't need one!

andrew@ems.Ems.MN.ORG (Andrew C. Esh) (02/09/88)

	The problem with the icons is not a new "bug" in Finder 6.0,
it is a misuse of the mask by some developers.  In Tech Note
#147, last paragraph, Apple tells us that the icon mask should be
just that, a "solid black copy of the icon, containing no holes."
The problem comes with the new color environment on the Mac II,
where the mask is needed to punch holes in what may be a color
background.  I have noticed bits of color hanging around inside
some icons after they have been moved or uncovered.  This is probably
because the mask wasn't there to clean up first.
	While I'm up here on the soapbox ... RTFM seens to apply more
to Mac developer's than most.  Probably because the Mac depends on the
developer to get things right, rather than have the user muddle through
life in the command line lane.  I'm reminded of the tourists in Florida who
gather wherever there is a "Do not feed the Alligators" sign to feed the
alligators.  Sooner or later, one of them gets chomped.  Pay attention,
folks, not so you can troop along behind some BIG company's standards, but
rather avoid the embarassment of getting your bits nibbled off as you
explore the frontier. :-)


-- 
Andrew C. Esh        DOMAIN: andrew@ems.MN.ORG     APPLELINK: D0492
EMS/McGraw-Hill      UUCP: ihnp4!meccts!ems!andrew      AT&T: (612) 829-8200