Visual Quirks?

Occasionally, my background Dolphin browser windows don't fully update
themselves. I get black vertical lines. Using Win2k. Anyone else
experience this or its my *^&# machine/OS setup thats screwed?

Jerome,

I have this problem and am also using Win2k.  I first noticed it in my own
application running with the DevelopmentSessionManager.  Later I noticed
that some Dolphin windows do the same thing, especially those containing a
TreeView.  Don't know yet to what extent this happens with a
RuntimeSessionManager.

Keith Alcock

Jerome Chan wrote:

> Occasionally, my background Dolphin browser windows don't fully update
> themselves. I get black vertical lines. Using Win2k. Anyone else
> experience this or its my *^&# machine/OS setup thats screwed?

Jerome,

> Occasionally, my background Dolphin browser windows don't fully update
> themselves. I get black vertical lines. Using Win2k. Anyone else
> experience this or its my *^&# machine/OS setup thats screwed?

I can't say I've seen black lines, but, I have seen "holes" in my screen -
areas that fail to repaint, often in toolbars and non-client areas.  When I
posted something (not long ago), I got the same answer you're getting: "you
are not alone".

Have a good one,

Bill

--
Wilhelm K. Schwab, Ph.D.
[hidden email]

In article <98ata8$ljq$[hidden email]>,
 "Bill Schwab" <[hidden email]> wrote:

Okay so does Object Arts have any answers? Its really annoying
(especially when the boss asks these questions over your shoulder).

Jerome,

> Okay so does Object Arts have any answers? Its really annoying
> (especially when the boss asks these questions over your shoulder).

Not really. AFAIK we've never seen this problem. We know of some issues
where the background of an applet running in Internet Explorer under control
of the plugin will sometimes not redraw correctly (leaving a white
background). We haven't anything similar in the development environment or a
normal Dolphin application. Without being able to reproduce this it's going
to be hard to fix. Do you have a reproduceable situation where this occurs?

Best Regards,

Andy Bower
Dolphin Support
http://www.object-arts.com

---
Visit the Dolphin Smalltalk WikiWeb
http://www.object-arts.com/wiki/html/Dolphin/FrontPage.htm
---

In article <98bvr0$18caf$[hidden email]>,
 "Andy Bower" <[hidden email]> wrote:

As far as I can tell it only happens under Win2k. I don't see this
problem on my Win98 machine at home. I'll try to take some screen shots
the next time it happens.

"Jerome Chan" <[hidden email]> wrote in message
news:[hidden email]...
> Occasionally, my background Dolphin browser windows don't fully update
> themselves. I get black vertical lines. Using Win2k. Anyone else
> experience this or its my *^&# machine/OS setup thats screwed?

I don't know if this has bearing on your problem with Dolphin, but during my
work on QKS Smalltalk for Win32 in 1996-97 I observed the same set of
problems. If you look in the bowels of MFC you will find that it has code to
"hack" around the same kind of update sequencing problems.

My solution in developing the frameworks for QKS Smalltalk was to use the
clipping system I developed for our Mac version. In effect, our Win32
version intercepts the OS paint/update messages calculates all the regions
itself and propagates the invalidations. This also made it easier to support
the transparency layering our <UIComponent> framework had on the Mac.

It also gave me exact control over the update sequencing, which in turn
enabled integration of double-buffered updates and also enabled guaranteeing
that a given piece of screen real-estate was only drawn/erased as needed (no
white update draw then erase flashes). The technique is fully compatible
with all windows components -- I just hooked into the lowest layer messages
and did the processing instead of the OS.  I learned a few of the tricks
from MFC.
==========

So, you ask, what has this to do with Dolphin Smalltalk?

My answer is that in working with the graphics and window updating/clipping
provided on the various flavors of Win32 I found that they not only were
different but that they sometimes failed to deliver the various messages in
the correct order such that clipping and vis regions calculations made by
the OS were actually wrong.

In other words, my first guess is that this is not a bug in Dolphin, but
more likely side-effect of a "feature" (intentional bug) in the OS and/or MS
Common Controls.
==========

To research my problem, and prove to myself that the problem was not in my
frameworks, I used SPY++ (spyxx.exe) to record the various update related
messages. At the time, I spent quite a bit of effort proving the problem to
myself. I.e., I used spy++ with identical UI layouts written in pure C code
to layout and manage the components, I wrote two different UI frameworks in
Smalltalk. And I did the same thing in MFC.

Hmm. Writing this post has jogged my memory (of some 4 years ago) a bit. I
recall that one of the big issues had to do with how the update was
generated.

  - By an invalidate message.
  - By a window of the "same" thread being moved to expose an area
  - By a window being made visible
  - By a window of a different "thread/process" being move to expose an
area.

Each of these generates different update sequences -- which also vary
slightly by Win32 platform.
==========

You ask, why you don't see it in other applications?

Most of them are built using a framework that has already addressed this
problem (such as MFC or VB).

Its been a while since I looked into the issue. But, as I recall when I
delved into this problem, I found comments in MFC framework sources and I
also read some obscure comments on this same issue in various Win32 books.

What I recall them describing was that this "bug" was actually intentionally
propagated into the current OS'es to support backwards compatibility of code
from a time when some original mistake/spec-error was made in Win3.1.

Cheers,

-- Dave Simmons [www.qks.com / www.smallscript.com]
  "Effectively solving a problem begins with how you express it."

Jerome,

"Jerome Chan" <[hidden email]> wrote in message
news:[hidden email]...
> Occasionally, my background Dolphin browser windows don't fully update
> themselves. I get black vertical lines. Using Win2k. Anyone else
> experience this or its my *^&# machine/OS setup thats screwed?

I just thought that I'd mention that in nearly a year of using Dolphin and
Win2000 together I've never noticed any unwanted black lines appearing in my
views, and it's the sort of thing I _would_ notice as I'm easily distracted
by such behaviour. I guess that even if it is a Dolphin problem it is also
linked to the machine (graphics card/drivers?) you are using.

Ian

Hi,
I noticed black vertical lines in background windows
on my machine, too. In a different setting, though:
OS is Win2K,
IBM VisualAge Smalltalk 5.5.1
and only when I use a large Arial font

There is an option in Win2K to turn on/off
"font smoothing" (Schriftarten glätten in German)
that seems to effect this behavior.
Maybe try to change this setting on your machine
and see what happens...

my 2c
Wolfgang

"Jerome Chan" <[hidden email]> schrieb im Newsbeitrag
news:[hidden email]...
> Occasionally, my background Dolphin browser windows don't fully update
> themselves. I get black vertical lines. Using Win2k. Anyone else
> experience this or its my *^&# machine/OS setup thats screwed?
>

I would chime in also to say that I have never seen this problem and I have
been running Dolphin on Win98, WinNT4, and Win2K for several years on
several successive different machines and a laptop.  I would perhaps also
suspect something hardware related or perhaps another errant application.

--
Regards,
Daryl

<< Sun, Zoom, Spark! >>

"Jerome Chan" <[hidden email]> wrote in message
news:[hidden email]...
> Occasionally, my background Dolphin browser windows don't fully update
> themselves. I get black vertical lines. Using Win2k. Anyone else
> experience this or its my *^&# machine/OS setup thats screwed?

"Jerome Chan" <[hidden email]> wrote in message
news:[hidden email]...
> Occasionally, my background Dolphin browser windows don't fully update
> themselves. I get black vertical lines. Using Win2k. Anyone else
> experience this or its my *^&# machine/OS setup thats screwed?

While driving down the road earlier today thinking about some e-mail I
received from Blair, I remembered yet another gotcha issue.

On WinNT/2000 the GDI architecture supports pipelined operations on a
per/thread basis. That means that certain GDI operations can be queued for
asynchronous processing.

You ask, so what impact would that have?

Well, I don't recall the details at this time. However, in framework code I
was developing for various blitting operations (circa 96-97) I had trouble
with updates on WinNT. I quickly discovered that I needed to make use of
GdiFlush, GdiSetBatchLimit, etc.

-- Dave Simmons [www.qks.com / www.smallscript.com]
  "Effectively solving a problem begins with how you express it."