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Old 10-26-05, 10:48 AM   #60
Mr. Nice
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Join Date: Jul 2005
Location: UK
Posts: 43
Default Re: Quak4 - Quake 4 tuning tool for NVIDIA G70/NV40/NV30 Series GPU's

Quote:
Originally Posted by ssj4goku887
im sorry to be the bearer of bad news but the performance settings DO decrease image quality... especialy fp16 and fp12.
Yeah your right, I said as much months back in the 3mood thread about fp16. On my 6800GT the performance advantage was quite negligible as well for this option.
As a point of order though, it's not fp12, that's fx12.

On another couple of the settings, both doom3 and quake4 actually use precision hint fastest in the standard interaction.vxp already, and quake 4 by default already does what the "swizzle" option does (which is mask the final result by xyz, ie skips writing out the redundant w channel). Indeed, quake 4's interaction.vxp is replete with quite aggressive write masks (as opposed to doom3's, which contains none). Finally, quake 4 already does the specular with maths, not a texture lookup, and indeed it does it with one less instruction then quak4/3mood . Quak4/3mood subtract's 0.75, squares it, then multiplies by 16, 3 instructions. Quake 4 uses a single MAD instruction to multiple by 4 then subtract 3, and then squares it, which is mathematically equivalent (multiplying by 4 before squaring is the same as multiplying by 16 afterwards, since 4 squared is 16, and similarly 3 is subtracted instead of 0.75 since 4x0.75=3).
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