I once had the idea to use space-filling curves to speed up CPU image convolutions by increasing the probability that 2D-adjacent pixels would be 1D-adjacent, a

I once had the idea to use space-filling curves to speed up CPU image convolutions by increasing the probability that 2D-adjacent pixels would be 1D-adjacent, and hopefully get loaded in the same cache line. IIRC the effect was measurable but not large enough to be worthwhile.