PC Ekspert Forum - Doom 3 Tweak Guide

GETTING ALL THE CVAR COMMANDS:

logfile 1 will create a log file of everthing that comes to the console after it's toggled. The logfile is in the D3 base directory and can be viewed better with "wordpad" than with "notepad".

listcvars -help in the console you get a list of all the cvars with a brief explanation of what they do. If you do this after toggling a logfile you'll get all the cvars in that log for you to peruse later.

UNDERSTANDING INDIVIDUAL CVARS FROM THE CONSOLE

listCvar [search string] = list cvar values
listCvar -help [search string] = list cvar descriptions
listCvar -type [search string] = list cvar types
listCvar -flags [search string] = list cvar flags

CVARS RELATED TO IMAGE QUALTIY AND PERFORMANCE

image_anisotropy set the maximum texture anisotropy if
available. (1,2,4,8,16)

SPECIAL NOTE: the below command is a very good tweak the will curb alot of hitching as textures are swapped back from memory to the HD. Use it! The more Ram you allocate the merrier but remember your system has other things to do than play D3 and D3 does more than just load textures. Remember also that if you have your AGP aperature size set to a large value you may not have an abundance or ram to spare in the first place. Try 1/2 of you available memory and scale from there.
image_cacheMegs maximum MB set aside for temporary loading
of full-sized precompressed images.

SPECIAL NOTE: This tweak is related to the former. Use it! The minimum should not exceed the the number from the previous tweak of course, but it "can" be just as large. If you do that though you will "guarantee" this much is dedicated to texture preloading. This is not so scary if you set the right value for the previous tweak and you're willing to give D3 that much love in the first place. REMEMBER WindowsXP or any other OS still needs RAM to run so make sure you leave enough available to keep your system stable. Also, Remeber the below tweak is in KB's not MB's so a conversion to MB's is needed to really understand what you're setting here. conversion factor: 1 MB = 1024 KB

image_cacheMinK maximum KB of precompressed files to read at
specification time.

SPECIAL NOTE: DO NOT use this tweak unless you have image_cacheMinK set to a LARGE value, and even then at you're own peril as it introduces instability after or during gameplay. If you don't head my warning I'll almost guarantee a crash to the desktop and that windows will be UBER laggy and you'll have to reboot. I would leave it set to zero which means off...OFF...I'd reeeeally leave it off until someone can show me it's worth all the crap it gives you.

image_useCache 1 = do background load image caching

image_colorMipLevels development aid to see texture mip usage. (I assume this is what is used to see mip transitions or identify faults if any with ATI's adaptive algorithm.)

downsampling = reduce size = lowers IQ = increases performance

image_downSize controls texture downsampling
image_downSizeBump controls normal map downsampling
image_downSizeBumpLimit controls normal map downsample limit
image_downSizeLimit controls diffuse map downsample limit
image_downSizeSpecular controls specular downsampling
image_downSizeSpecularLimit controls specular downsampled limit

I don't know the preset values D3 uses for any of the above. Given how D3 looks you probably don't need to mess with them, but I think if you change you IQ setting in-game and come back to the config file these values will change and you can then determine which D3 uses at the point.

image_filter changes texture filtering on mipmapped
images. (GL_linear_MIPMAP_nearest = billinear= lower IQ and ups performance, GL_linear_MIPMAP_linear = trillinear= higher IQ and incurs a performance hit)

image_forceDownSize (this is a toggle that will lower IQ, but probably up performance. 1 = on, 0 =off)

image_ignoreHighQuality (0=off,1=on)ignore high quality setting on materials. (never use this unless you have to, because you won't see D3 in all it's glory. This probably ensures bump, normal maps, and specular maps all still get compressed even if you select high quality IQ in the ingame menu = meh!!!)

image_lodbias change lod bias on mipmapped images(0= normal,-value= better IQ and lower performance, +value=worse IQ and better performance as the detail is either uped or lowered on textures/materials)

image_roundDown round down to nearest power of two. (toggles rounding down of bump, specular, normal maps I assume. This is probably on valuable if you use low quality settings but you don't want your texture IQ lowered so much. 0=off so try and see if it makes low or even medium quality look a little better. Remember AF is still off unless you force it on outside the game in low and medium IQ settings.)

image_useAllFormats allow alpha/intensity/luminance
luminance+alpha. (leave this on fools!)

image_useCompression 0 = force everything to high quality(This would seem the better tweak for making low and medium setting look better than they should. Haven't tested it yet though.)
image_useNormalCompression 2 = use rxgb compression for normal maps, 1
= use 256 color compression for normal maps
if available (I have no idea which is better at the moment, other than zero means no normal map compression and that's the best IQ setting.)

r_multiSamples number of antialiasing samples.(AA at 0,1,2,4,6 for ATI, 8 for Nvida)

r_renderer everthing is simply "opengl" now, but perhaps the old NV30 etc paths still exist)

r_sb_linearFilter use GL_LINEAR instead of GL_NEAREST on
shadow maps(this will use trillenear over billinear filtering on shadow maps for better IQ, and lowers performance)

r_shadows enable shadows(O=off,1=on)(this may be the most significantly insignificant tweak ever. If you remove the shadow you will get a real performance spike...but D3 will look like your naked, crack lovin, unshaved, skin-diseased grandmother after a long night out with 2 baboons to many working the train and she's miffed because she didn't even get paid for the muffs she gave them! Don't do it unless your rig sucks so hard it's giving lewenski lessons and you just have to say you got D3 working on your worthless pile of ****! Not scathing enough? UPGRADE YOU CHEAP **** before you even consider turning shadows off...unless you're a total douche bag. Then...by all means...turn shadows off. )

SPECIAL NOTE:These cvars are related to high dynamic range lighting I presume and I don't know whether they work or not. Someone with either an X800 or 6800 will have to test these. Oh, and I'm quite sure whoever does will incur a performance hit. Surprise me. Please?

r_hdr_bloomFraction fraction to smear across neighbors
r_hdr_exposure maximum light scale
r_hdr_gamma monitor gamma power
r_hdr_monitorDither random dither in monitor space
r_hdr_useFloats use a floating point rendering buffer

r_jitter randomly subpixel jitter the projection(I don't know what that means, but I'm told that if it's toggled on it makes things look better.)

It should be said there are ton of other cvars to play with with respect to IQ and performance particularr the g_skip ones where you can turn off stuff to increase performance. There were too many to list and give explanations for so I would ask you check these out yourselves. If you find anything of value of course let us all know.

UNLOCKING NIGHTMARE MODE AND A FEW CHEATS IT SEEMS!

nightmare mode is a 0,1 toggle and the health options are I assume 0 to 100% respectively.

g_healthTakeAmt how much health to take in nightmare mode
g_healthTakeLimit how low can health get taken in nightmare mode
g_healthTakeTime how often to take health in nightmare mode
g_nightmare toggles if nightmare mode is allowed

MOVEMENT TWEAKS

pm_bobpitch
pm_bobroll
pm_bobup
pm_crouchbob bob much faster when crouched
pm_crouchheight height of player's bounding box while crouched
pm_crouchrate time it takes for player's view to change from standing to crouching
pm_crouchspeed speed the player can move while crouched
pm_crouchviewheight height of player's view while crouched
pm_deadheight height of player's bounding box while dead
pm_deadviewheight height of player's view while dead
pm_jumpheight approximate hieght the player can jump
pm_maxviewpitch amount player's view can look down
pm_minviewpitch amount player's view can look up (negative
values are up)
pm_modelView draws camera from POV of player model (1 =
always, 2 = when dead)
pm_noclipspeed speed the player can move while in noclip
pm_normalheight height of player's bounding box while
standing
pm_normalviewheight height of player's view while standing
pm_runbob bob faster when running
pm_runpitch
pm_runroll
pm_runspeed speed the player can move while running

pm_stamina length of time player can run
pm_staminarate rate that player regains stamina. divide
pm_stamina by this value to determine how
long it takes to fully recharge.
pm_staminathreshold when stamina drops below this value, player
gradually slows to a walk
pm_stepsize maximum height the player can step up
without jumping
pm_walkbob bob slowly when walking
pm_walkspeed speed the player can move while walking

THIRD-PERSON TWEAKS

pm_thirdPerson enables third person view
pm_thirdPersonAngle direction of camera from player in 3rd
person in degrees (0 = behind player, 180 =
in front)
pm_thirdPersonClip clip third person view into world space
pm_thirdPersonDeath enables third person view when player dies
pm_thirdPersonHeight height of camera from normal view height in
3rd person
pm_thirdPersonRange camera distance from player in 3rd person
pm_usecylinder use a cylinder approximation instead of a
bounding box for player collision detection (not a really a 3rd person tweak and I assume it will allow to slide off things more easily)

http://www.rage3d.com/board/showthread.php?t=33773634