I tried Mip Map dithering on my Voodoo 5 AGES ago on one game, Ultima IX, and all I noticed was that mip maps had a ugly dithering between them which was probably more distracting than normal bilinear mip map levels. I turned it off never touched the option again.
Until today, when I was playing around with my old system. I turned it on and fired up Quake 3. Being used to the rather obvious mip mapping in Quake 3, especially with certain floor textures, I was AMAZED at how it looked with mip map dithering on. It looked damn close to trilinear! This was something I never thought the card could do. It didn't look anything like the actual "dithering" that I remember. There was a smooth gradiation between mip map levels.
Needless to say, I'm rather shocked at having missed out on that IQ improvement at the time. Of course now I use anisotropic on my new syste, it still looks crap by comparison, but it looks a lot better than bilinear.
Now the 3dfx help says this is achieved by blending between mip map levels. Isn't that basically what has been said about NVIDIA and it's cheating trilinear or "brilinear" filtering? Or is it yet another fake trilinear method?
I have always found it sucks so I've always disabled it
but it really looks good in quake3, thanks for the info :)