Anyone with problems with ATI drivers read this.

[dduff442]

While you're right to complain about the bugs, I did manage to get acceptable performance after a lot of painful experimentation. My system has an i7/920 CPU with an ATI HD5870 GPU, but the settings here should be useful to anyone with a recent ATI card.

The simple solution is to use DirectX with the latest Catalyst driver update. I haven't tested this extensively but it delivered excellent FPS performance. The only problem I noticed was that the landscape tended to momentarily break up into black squares whenever the viewing angle was shifted suddenly.

The other problems with DirectX in il2 are one that the water is flat and not nearly as pretty as in OpenGL and two that 'perfect' graphics mode is unavailable. 'Perfect' mode doesn't matter except in clear weather (apparently) when it doubles the draw distance. I did manage to get both these features working in OpenGL as I'll explain.

With the latest ATI drivers (10.2), il2 is pretty much unplayable in OpenGL mode due to the problems of text corruption etc. Dropping a copy of version 9.1 of the ATI OpenGL driver into your il2 directory will allow you to use 9.1 for il2 (which works fine) and 10.2 for everything else.

So... after a lot of messing around, I finally arrived at what I consider the optimal settings:

First the screen resolution:

[window]
width=1920
height=1200
ColourBits=32
DepthBits=24
StencilBits=8
ChangeScreenRes=1
FullScreen=1
DrawIfNotFocused=0
EnableResize=0
EnableClose=1
SaveAspect=0
Use3Renders=0

[GLPROVIDER]
GL=Opengl32.dll

These settings will work for any widescreen etc. monitor unsupported by il2 simply by altering the width and height parameters to fit your monitor's native resolution.

Now to the Graphics settings:

[Render_OpenGL]
TexQual=3
TexMipFilter=2
TexCompress=0
TexFlags.UseDither=1
TexFlags.UseAlpha=0
TexFlags.UseIndex=0
TexFlags.PolygonStipple=1
TexFlags.UseClampedSprites=0
TexFlags.DrawLandByTriangles=1
TexFlags.UseVertexArrays=1
TexFlags.DisableAPIExtensions=0
TexFlags.ARBMultitextureExt=1
TexFlags.TexEnvCombineExt=1
TexFlags.SecondaryColorExt=1
TexFlags.VertexArrayExt=1
TexFlags.ClipHintExt=0
TexFlags.UsePaletteExt=0
TexFlags.TexAnisotropicExt=1
TexFlags.TexCompressARBExt=1

TexFlags.TexEnvCombine4NV=0
TexFlags.TexEnvCombineDot3=1
TexFlags.DepthClampNV=0
TexFlags.SeparateSpecular=1
TexFlags.TextureShaderNV=0

HardwareShaders=1

Shadows=2
Specular=2
SpecularLight=2
DiffuseLight=2
DynamicalLights=1
MeshDetail=2
VisibilityDistance=3

Sky=2
Forest=3
LandShading=3
LandDetails=2

LandGeom=3
TexLarge=1
TexLandQual=3
TexLandLarge=1

VideoSetupId=8
Water=0
Effects=0
ForceShaders1x=0

PolygonOffsetFactor=-0.15
PolygonOffsetUnits=-3.0

I get around 32-45fps under 'normal' conditions with these settings. The 'Black Death' shows around 30-35fps on average, dropping to a minimum of around 22 in effects-heavy moments. I know that last figure sounds alarming, but I didn't notice it to be a serious problem in terms of the visual experience.

Setting effects at 1 tended to cause nasty fps hits during explosions etc. Setting water=1 (or higher) radically hurt fps performance. FRAPS showed 17 or so with water=1 but the ground was actually chugging past at around 5fps while only aircraft were showing the 'true' 17fps.

Water=0 is actually ok, still miles better than the DirectX version, and I don't think many people will miss the shadows from effects that effects=1 permits.

The good news is I can ramp anti aliasing, anisotropic filtering etc up to the limit in Catalyst Control Center without hurting the fps count in any way. As far as I can make out, the problem is that the Nvidia-optimised code is dumping extra load onto the CPU and that this is the limiting factor rather than GPU performance. Experimenting with lower resolutions did not produce an improvement in fps performance that I could see.

The game does look really well under these settings and the extra draw distance means that objects 'popping up' are much less obvious than with DirectX. Flying low over Slovakia or the big port town in the MTO map is particularly nice here and missions that use, e.g., smoke markers to designate targets will be easier when the smoke is actually visible from more than a few kilometers away.

At 30-40fps, some 'tearing' when rapidly shifting the angle of viewing, as with using a hat switch, will be apparent to those with sensitive eyes. It isn't a big issue for me, though, so unless you're one of those very few people who are sensitive to fps rates below 60 I'd suggest using the settings shown. Shooting games etc. can be painful enough at 30fps but Il-2 isn't really a 'twitchy' sort of game so I think I'll be sticking with this setup.