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Old 10-26-05, 02:09 PM   #66
tertsi
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Join Date: May 2003
Posts: 340
Default Re: Quak4 - Quake 4 tuning tool for NVIDIA G70/NV40/NV30 Series GPU's

Quote:
Originally Posted by Mr. Nice
It's those ubiquitous (in both doom3 and quake4) floor gratings, they look fairly fugly with fp16 on (and that's on my 6800GT, ie NV40). Using short temps though is fine.
I haven't noticed any problems with/without ARB_precision_hint_fastest, FP16 ALU Operations or Short Temps (75 or 80 series drivers).

Quote:
Originally Posted by Mr. Nice
Hmmn? If SUB/MUL/MUL uses one more cycle then MAD/MUL (which seems fairly intuitive), why would it be 1-2fps faster? Especially since one of your other optimizations is to replace a MUL/ADD with a MAD? (Although I do see why it was left as MUL/ADD, it looks neater due to the ADD being the summation of the results of two lots of SUB/DP3/RSQ/MUL's).
Well 1 cycle more gpu time in NVShaderPerf doesn't mean really nothing... like I said, "SUB/MUL/MUL" is faster IN DOOM 3 than "MAD/MUL"

MUL/ADD optimization is for vertex programs.
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