在nvnews的论坛我们发现了国外玩家写的一篇《使命的召唤2》的性能优化帖子。这名玩家使用6800GT在1024x768都跑的不顺，因此研究r_ console命令制作了优化版config文件。

研究过程中该玩家发现了两处和游戏性能相关的bug：

1.r_multigpu，默认值为0，也就是对应图象设置中的“optimise for SLI”项。即使你只有单显卡，打开这个选项（即命令r_multigpu 1）就能获得5-20%的性能提升。游戏正式版还存在这样的重大bug真是不可思议。

2.r_applypicmips。这个命令的作用就是修改贴图质量后无需vid_restart（也就是重新loading）。有趣的是使用这个命令后我们可以得到另外的5-20%性能提升，当然要让这个使用这个命令需要先修改贴图质量（picmip 0/1/2）。

基于这两点，再加上其他的性能调整命令，这名玩家制作了cod2tweakconfig包，使用方法如下：

1.打开cod2tweaks.zip（点击下载）将里面的autoexec.cfg和tweak.cfg拷贝到Call of Duty 2\main\目录下。

2.进入游戏-option-game option，“enable console”设为“yes”。

3.load game后按“~”调出控制台，输入exec autoexec.cfg。该步骤是将autoexec.cfg的内容写入config.cfg，只需执行一次。

4.按“.”键，该键已经被绑定exec tweak.cfg，以后每次换地图后都要重复此步骤。

另外，在游戏中还可以按“，”和“/”来切换帧数显示/关闭。

下面几张截图是这名玩家优化前和优化后的画面和帧数对比。画面设置为1280x720，2xAA，4xAF，最高画质。显卡为6800GT @ 375/1100。上图为优化前下图为优化后。

hmm，优化前后画面看不出什么差别，而帧数显然提升了不少，对DirectX 7还是DirectX 9模式都适用哦，感觉cod2跑得不爽的朋友们还不赶紧试试。

这个帖子的原文及cod2tweaks.zip（帖子附件）下载在这里。

另附autoexec.cfg和tweak.cfg文件内容，也可以手动创建这两个文件（新建文本文件，复制粘贴，改文件名）。

autoexec.cfg：

//this file contains variables that must be changed before the map loads, if you alter these values after map load, you must run "vid_restart" in console to enable the changes.

//You must still press . after each map load to enable the picmip fps boost contained in tweak.cfg.

//press to enable the tweak.cfg after each map load

bind . "exec tweak.cfg"

//press to enable fps meter

bind , "cg_drawFPS 1"

bind / "cg_drawFPS 0"

//saw this on the planetcod forums, unknown benefits, may reduce mid game stutter, set no higher than half total system ram.

seta com_hunkmegs "512"

//unknown, has no negative effect on fps, possible increase in places? anyone willing to research this, thanks.

seta r_autopriority "1"

//anisotropy level, default is 8, personal preference, i find 4 gives noticeably better performance for little IQ loss.

seta r_anisotropy "4"

//Not too sure, i think it's for antialiasing alpha channel in textures, eg sprites for smoke etc. 0 is off, 1 is fast dither, 2 is supersampling. 0 and 1 perform equally.

//if you have performance to spare, try running on 2, you lose ~1fps when i tested it briefly, but i could not see an IQ difference from 1.

seta r_aaAlpha "1"

//fixes broken default r_gpusync 3 slowdown. Leaving multigpu at 0 and setting gpusynch to 0 achieves the same fps boost, however this will break things for sli users.

//There is no performance loss running multigpu 1 on a single gpu. Improves minimum fps by 5-20%, depending on what you're looking at ingame.

seta r_multigpu "1"

tweak.cfg:

//3 commands to fix the picmip bug related fps loss, change last picmip value to your preferred detail level, (look in config.cfg for value).

//Also increases framerate noticeably, 5-15% depending on scene.

r_picmip "2"

r_applyPicmip

r_picmip "0"

r_applyPicmip

//zfeather value (soften smoke edges), 0 disables for better performance, 1 enables. disabling (0) improves framerate by 5-20% when smoke is visible onscreen.

//speed benefits of disabling largely depends on how close you get to the smoke. Ditto for IQ benefits if enabled.

//couldn't locate the command controlling world/everything option, you must set that in the graphics menu first. "World only" is recommended IQ/speed tradeoff.

//set to 1 here despite the fps boost - you will notice the lines of smoke edges ingame otherwise.

r_zfeather "1"