ok, so when I use samplelevel at the 0th level it seems to go slower when i just use sample and autodetect the level. Is samplelevel slow? or is it only going slow because its checking the final level, where sample is picking off mips instead?
i think im right, just clear my mind, thanks.
Forcing things to a lower mip level can indeed make rendering slower since you'll have more texture cache misses. But I would only expect that to happen when you're far enough away from the texture that it wouldn't use the lower mip level at all under standard sampling.
I am far far away from the texture, its right in the sky looking at a water body - so yeh it comes up.
machine wise you kill me,thanks for the info.