[Driver issue]ATI Fog problems (formerly: Blinking lights.)

Deathlike2 · Post by **Deathlike2** » Fri Nov 11, 2005 23:00

I can confirm what you are seeing.. I think..

I'll post what I'm seeing (just to make sure)

I'm looking at a split between the two "fog areas"...

Post by **Graf Zahl** » Fri Nov 11, 2005 23:04

That's not fog in the second screen shot. It's just an under water blend that is derived from the fog set by a 3D-floor. 3D-floors can't define real fog.

Post by **solarsnowfall** » Fri Nov 11, 2005 23:06

Drat!

Ixnatifual · Post by **Ixnatifual** » Thu Nov 24, 2005 14:57

Just noticed I have the same issues with fog.

ATI Radeon X850 XT Platinum.

Deathlike2 · Post by **Deathlike2** » Sat Nov 26, 2005 21:01

I'm confused at how the depth fog is done.. is it done by some sort of extension.. or by some shader?

If it happens to be some shader, have you verified the syntax through a shader validator app? I recall that NVidia is lax when it comes to syntax and ATI is very strict to the standard..

Post by **Graf Zahl** » Sat Nov 26, 2005 23:05

This is standard hardware fog. Ati's driver seems to screw up when it clips the polygons to the visible area of the screen.

Deathlike2 · Post by **Deathlike2** » Thu Jan 05, 2006 23:38

When you implement the depth fog, are there parameters you can tweak the fog with?

If there is, can you provide a method to change these parameters so I can see which might be the best option for ATI video cards?

I will also check this on my NVidia hardware to see if there are no ill effects of the change.

Post by **Graf Zahl** » Thu Jan 05, 2006 23:51

The only parameters you can set for fog are density and color, both of which are handled according to the current objects being rendered. The ATI problems have nothing to do with the fog settings. It seems there's a bug in the driver that transfers them incorrectly when a polygon has to be clipped to the screen.

Post by **Graf Zahl** » Sat Jan 07, 2006 14:55

Moving to Closed Bugs. This is a driver/hardware issue I can't fix so there's no need to sticky this at the top of the bugs forum.

Hobbs · Post by **Hobbs** » Mon Jan 09, 2006 17:50

A small note for you ATi users: Installing Omega Drivers fixes this for me (actually I've never used standard ATi drivers since I got my machine, but I've never had problems in GZDoom either) so I reccomend you check those out to try and fix it.

Whoops. I forgot to mention that if you dont read the compatable cards list before you get them, its your fault if they screw up your system. Because they seriously do not work for cards/chipsets not on that list.

Post by **Graf Zahl** » Mon Jan 09, 2006 17:53

Interesting. So it is indeed a driver and not a hardware issue. As I suspected.

Jin · Post by **Jin** » Mon Jan 09, 2006 18:27

To confirm what Hobbs said, I too use the Omega drivers. No problems at all on both a Radeon 9000 and a Radeon X700.

Deathlike2 · Post by **Deathlike2** » Thu Jan 19, 2006 13:27

I see, but then I have some questions...

What version of Omega Drivers (well, the version of the CATALYST driver that it was based on) worked for you?
Does the latest version (that support CATALYST 6.1) work as well?
Do you have any idea why it works? (the settings/registry entries used to fix the bug...Have you asked the authors? I would like to see if I can find a way to reproduce it on the official drivers using ATI Tray Tools if at all possible, or at least use the same GL driver Omega uses and see if that makes a difference.)

Deathlike2 · Post by **Deathlike2** » Thu Jan 19, 2006 16:18

Hmm.. it still doesn't work...

What ATI hardware are you using Hobbs? That's what I'd like to know...

The Omegadrivers (based on CATALYST 6.1) failed to fix this problem... what I do think that this bug was introduced in an older set.. but I still need to know which one.

Edit: Even better, tell me what the version of the OpenGL driver was as reported by GZDoom... that's would before more useful.