[Bug 31071] New: DotA 2: overbright/broken lighting effects

http://bugs.winehq.org/show_bug.cgi?id=31071

Bug #: 31071
           Summary: DotA 2: overbright/broken lighting effects
           Product: Wine
           Version: 1.5.7
          Platform: x86-64
        OS/Version: Linux
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: -unknown
        AssignedTo: [e-mail]
        ReportedBy: [e-mail]
    Classification: Unclassified

(This is a lengthy one because there are already lots of observations and
attempt-fixes to describe.)

DotA 2 is suffering from weird overbright lighting effects issues, best seen on
these screenshots:
appdb.winehq.org/appimage.php?iId=39263
appdb.winehq.org/appimage.php?iId=39265

All heroes, items and buildings having some lighting effects are affected.
Static map decoration (flares, ...) is not (or at least to a very minor
extent).

Steps to reproduce:
- start the game client and create a lobby in all-pick mode
- start the match and pick Lina
- have a look at what's supposed to be the hero's flaming hands, or at the
visuals of her second spell

See the attachend image for a direct comparison (what it SHOULD vs. what it
DOES look like).

My personal observations regarding the problem:
- does not seem to occur with other source engine games (HL2, Portal2, L4D2)
- persists throughout:
-- ubuntu 11.04, 11.10, 12.04
-- the propriatary nvidia graphics driver series 295.xx to 302.17 (and most
likely also before)
-- wine 1.3.x, 1.4.x and 1.5.x up to 1.5.7
-- 32bit and 64bit systems
-- kernel versions 2.6.x to 3.2.0-26-generic
-- various window managers (2D as well as 3D-enabled ones)
- the only wine registry setting having an effect on the problem seems to be
"OffscreenRenderingMode = backbuffer"
-- setting it, the overbright effect is gone, but pretty much anything else
gets messed up (ambient lighting is too low and somewhat greenish; continuity
of visual effects is broken, etc)
- no imgame setting / console variable seems to have an effect
- none of the options in the 'nvidia-settings' tool has an effect
- creating a fresh 32bit wine prefix with 'WINEARCH=32bit' (instead of
defaulting to 64bit) has no effect
- confirmed to happen on Geforce GTX 8800, GTX 260, GT 330M

Note:
Unlike other source games, DotA 2 must be run with the '-nod3d9ex' parameter.
Otherwise it won't render at all. However, doing so does not cause the
described visual issues on Windows.

I am currently using:
- wine-1.5.7, GeForce GTX 260, nvidia driver 302.17, Xubuntu 12.04 x64
(xfwm4.10.0), kernel 3.2.0-26-generic

I am suffering from this bug
http://bugs.winehq.org/show_bug.cgi?id=30270
which MIGHT be related to the problem (though I have no evidence to prove this
assumption right or wrong).

The three provided logs were created with
WINEPREFIX=~/.wine/dota2 wine Steam.exe &> dota2.txt
and split around:
- steam being fully loaded
- dota 2 being fully loaded
- creating a lobby, starting the match, picking a hero and entering the game
map
(gonna add the logs to messages below this one because I cannot create several
attachments...)

Though it only seems like a cosmetic problem, this bug results in a SEVERE
impact on gameplay, since the player loses track of what's happening when only
seeing huge overbright explosions.

Also note the discussion taking place on the game's AppDB site
(http://appdb.winehq.org/objectManager.php?sClass=version&iId=24458), under the
message "Weird lighting effects bugs/issues", for some more details.