T2: So, fog is broken again. *sigh*

Yandros on 2/1/2010 at 19:04

Since he's running XP, either nVidia or ATI should work fine for fog. I have always had great fog on my XP machine with an nVidia card.

SiO2 on 3/1/2010 at 18:32

I may have fixed fog for Thief2 - it's working on my machine now after some modification of the ddfix source code to workaround a couple of bugs.

I've posted the new ddfix dll and a request for beta-testers in the forum (http://www.ttlg.com/forums/showthread.php?p=1949608) here.

bikerdude on 3/1/2010 at 20:06

Quote Posted by SiO2

I may have fixed fog for Thief2 - it's working on my machine now after some modification of the ddfix source code to workaround a couple of bugs.

Monster!

SiO2, you are indeed a star!

Right people, get testing. I will in due course on my nVidia based laptop..

:thumb::thumb::thumb:

Yandros on 3/1/2010 at 20:26

I'll check it out tonight on my Vista64 ATI machine. This is awesome, SiO2!

jtr7 on 3/1/2010 at 21:30

Fantastic! You people are so cool!:cheeky:

SiO2 on 3/1/2010 at 23:58

I tested on Windows 7 x64 with nvidia GTX260 and 195.62 drivers.

Life Of The Party, which is what I mainly tested with, seems fine - in fact it makes a massive difference to the ambience (and I haven't seen fog myself in T2 for years!). Casing may have a problem - it's totally black for me at the start of the level. I just tried Rose Cottage and that seems the same as Casing. I'll try Calandra's Legacy next.

So it may be that some things (projection matrix) need tweaking. The main thing is that I now know what the main problem is with fog in Thief2. Actually there are two issues:
1. Thief2 does not set a proper projection matrix. Since Thief2 does it's own matrix transformations and passes the results to Direct3D this usually doesn't matter, but for fog these old D3D hardware drivers need a 4D W-friendly projection matrix so they can inverse-project back to worldspace. Once I gave Direct3D a projection matrix I got some fog in LOTP (Life Of The Party), though I had to make an educated guess at some of the parameters required to calculate the matrix. This is a fix I would expect in an IHV driver. I assume ATI detect thief2.exe and use a substitute projection matrix. I also assume that nVidia had this in earlier drivers, but dropped support for the game or made new drivers and didn't carry the patch forwards. This W-friendly projection matrix stuff was a bitch to find - I had to trawl docs for notes regarding 10-year old interfaces.
2. I then had fog, but once I moved into the level it stopped being rendered. There are effectively two fog switches in D3D. I founf that if T2 had fog-table-mode enabled then I needed to enable the "main" fog-enable switch also. Could be a bug in T2 or a bug in D3D that T2 relied on, that's since been fixed.

Anyway, I'll try Casing again and tweak the projection matrix and see if I can fix it. I'd be interested in feedback reagrding LOTP and/or other missions with fog though!

d'Spair on 4/1/2010 at 00:18

SiO2, see my posts in the Techinical forums thread. The fog works great at all three foggy missions, but I get black screen at any missions that do not use fog. Casing the Joint doesn't use fog, unlike Masks, that's why you got the black screen. :)

It also makes the sky not rendered in Thief 1.

Fog is partically broken in Life of a Party, and it always has been - it vanishes when you move a few blocks away from the starting point. So it it is not an issue on ddfix's side.

SiO2 on 4/1/2010 at 00:26

Quote Posted by d'Spair

Casing the Joint doesn't use fog, unlike Masks, that's why you got the black screen. :)

Aha! Excellent information. :thumb:

Quote Posted by d'Spair

It also makes the sky not rendered in Thief 1.

Thanks for the heads-up! I'll test T1 ASAP.

SiO2 on 4/1/2010 at 00:32

Quote Posted by jtr7

No fog in Shipping....

Just Life of the Party, Precious Cargo, and Masks.

Grade A information. I wrongly assumed both Casing and Masks had fog.

Anyone have a list of which of the Thief1/Gold OM's have fog?

d'Spair on 4/1/2010 at 00:39

None of them have fog, since weather effects and fog are not supported in Thief 1/Gold. However, people use ddfix in Thief 1/Gold in order to get rid of some rendering problems, and also to enjoy 16-bit color in the game.

I have no idea whether fog is supported/used in System Shock 2 or any FMs.

SiO2, you stated you got a black screen on Rose Cottage FM. Does that FM use fog?

Quote Posted by d'Spair

Fog is partically broken in Life of a Party, and it always has been - it vanishes when you move a few blocks away from the starting point. So it it is not an issue on ddfix's side.

Oddly enough, I've just made another test run of Life of the Party, and fog worked perfectly while I was walking around the mission. Whether it magically got fixed, or my memory fails me, and it has been so for all the time.