Here’s a tricky one

Lorand · 08-27-2004, 04:50 PM

So it's only a coincidence... Still don't know what it could be...

Interestingly all the computers that produces black background have ZoneAlarm installed. Could this be the problem?

Lorand · 08-27-2004, 05:17 PM

Look what I found (so I'm not alone with this problem):

Code:

// Not clear why this is need to clear whole background to white;
// otherwise -- only sometimes -- part of bitmap is black instead.
RESULT.Canvas.Brush.Color := clWhite;
RESULT.Canvas.FillRect( RESULT.Canvas.ClipRect );

This would be the solution, but I can't use it without the source...

So I'm still hoping there's a windows setting that could solve the problem...

**Praetor** · 08-27-2004, 08:13 PM

Quote:

Interestingly all the computers that produces black background have ZoneAlarm installed. Could this be the problem?

Now ur shooting in the dark!

(no worries... been there done that.... still there

)

I'll have a look around.. gimme some time ... been busy.

Lorand · 08-28-2004, 12:36 AM

I FIGURED OUT AT LAST!

At the display settings I changed the color depth from 32 bpp to 16 bpp and the program works fine now!
But what the heck could be the difference between these two video settings?

**Praetor** · 08-28-2004, 03:19 PM

What about 24bit ... oh and btw not to ruin your parade.... mine is on 32bit color and works fine (also works on 16 and 24)

Lorand · 08-28-2004, 03:25 PM

I only have 16 or 32 at color depth options (my card is an ATI All-in-wonder), so I can't check what happens at 24 bit...
Could be a video-driver bug that produces that bitmap black-out?

**Praetor** · 08-28-2004, 04:00 PM

Maybe an ATI/nvidia dealy? I wouldnt think so cuz i dont have any problems on my ATi based systems. What driver revisions have you tested on?

Lorand · 08-28-2004, 04:58 PM

It's surely not an ATI/Nvidia thing, because on another computer there's an Nvidia and the background is also black.
I'll test that computer's video settings too in a couple of days...

**Praetor** · 08-28-2004, 09:55 PM

Quote:

It's surely not an ATI/Nvidia thing

I figured but i guess it was worth a shot in the dark

Lorand · 08-29-2004, 11:59 AM

Tested the NVidia too. And it works the same way: 32 bpp -> black, 16 or 24 bpp -> white.
On my computer I had 3 versions of ATI drivers so far, and every time it was a bitmap blackout. But I had the same video card and display settings on Win98 too, and it was ok...

So:
1. Only happens in XP
2. This problem does not affect all systems
3. Not depends on video card manufacturer
4. It's not a driver bug
5. Only happens in 32 bpp
6. Not depends on any other settings (transparencies, etc.)

What could it be then?

08-27-2004, 05:17 PM	#22 (permalink)
Lorand VIP Member Join Date: Dec 2003 Location: Bucharest Age: 42 Posts: 3,042	Look what I found (so I'm not alone with this problem): Code: // Not clear why this is need to clear whole background to white; // otherwise -- only sometimes -- part of bitmap is black instead. RESULT.Canvas.Brush.Color := clWhite; RESULT.Canvas.FillRect( RESULT.Canvas.ClipRect ); This would be the solution, but I can't use it without the source... So I'm still hoping there's a windows setting that could solve the problem...

08-28-2004, 03:19 PM	#25 (permalink)
Praetor Administrator Join Date: Jul 2004 Location: Canada Age: 25 Posts: 19,954	What about 24bit ... oh and btw not to ruin your parade.... mine is on 32bit color and works fine (also works on 16 and 24) __________________ ASUS P5K Premium WiFi-AP, Q6600@3.7 / ASUS P5ND, E6400@3.8 4GB OCz Platinum XTC 8500 / 4GB CorsairXMS2 6400 5x500GB Seagate 7200.10 / 2x500 Seagate 7200.10 OCz 8800GTX 768MB @ 630/800 / 2x Galaxy 8800GT SLI

08-28-2004, 04:00 PM	#27 (permalink)
Praetor Administrator Join Date: Jul 2004 Location: Canada Age: 25 Posts: 19,954	Maybe an ATI/nvidia dealy? I wouldnt think so cuz i dont have any problems on my ATi based systems. What driver revisions have you tested on? __________________ ASUS P5K Premium WiFi-AP, Q6600@3.7 / ASUS P5ND, E6400@3.8 4GB OCz Platinum XTC 8500 / 4GB CorsairXMS2 6400 5x500GB Seagate 7200.10 / 2x500 Seagate 7200.10 OCz 8800GTX 768MB @ 630/800 / 2x Galaxy 8800GT SLI

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08-27-2004, 04:50 PM	#21 (permalink)
Lorand VIP Member Join Date: Dec 2003 Location: Bucharest Age: 42 Posts: 3,042	So it's only a coincidence... Still don't know what it could be... Interestingly all the computers that produces black background have ZoneAlarm installed. Could this be the problem?

08-28-2004, 12:36 AM	#24 (permalink)
Lorand VIP Member Join Date: Dec 2003 Location: Bucharest Age: 42 Posts: 3,042	I FIGURED OUT AT LAST! At the display settings I changed the color depth from 32 bpp to 16 bpp and the program works fine now! But what the heck could be the difference between these two video settings?

08-28-2004, 03:25 PM	#26 (permalink)
Lorand VIP Member Join Date: Dec 2003 Location: Bucharest Age: 42 Posts: 3,042	I only have 16 or 32 at color depth options (my card is an ATI All-in-wonder), so I can't check what happens at 24 bit... Could be a video-driver bug that produces that bitmap black-out?

08-28-2004, 04:58 PM	#28 (permalink)
Lorand VIP Member Join Date: Dec 2003 Location: Bucharest Age: 42 Posts: 3,042	It's surely not an ATI/Nvidia thing, because on another computer there's an Nvidia and the background is also black. I'll test that computer's video settings too in a couple of days...

08-29-2004, 11:59 AM	#30 (permalink)
Lorand VIP Member Join Date: Dec 2003 Location: Bucharest Age: 42 Posts: 3,042	Tested the NVidia too. And it works the same way: 32 bpp -> black, 16 or 24 bpp -> white. On my computer I had 3 versions of ATI drivers so far, and every time it was a bitmap blackout. But I had the same video card and display settings on Win98 too, and it was ok... So: 1. Only happens in XP 2. This problem does not affect all systems 3. Not depends on video card manufacturer 4. It's not a driver bug 5. Only happens in 32 bpp 6. Not depends on any other settings (transparencies, etc.) What could it be then?