Hmm, that picture *does* show cubic interpolation blurring the pixels
together too much.

I always thought bi-cubic interpolation was really just bi-linear
interpolation with the points interpolated between in a smoother manner.
Like, if you graphed a row of pixels interpolated with bi-linear
interpolation, you'd have a bunch of points connected with straight lines,
but if you graphed it with bi-cubic interpolation, you'd have a bunch of
points connected with curves that match the curve

y = -2*x^3 + 3*x^2 = x^2*(3-2*x)

from x=0 to 1. (the second expression is equivalent but faster to calculate
with a computer, I believe. I took it from the noise generator source code.)

 - Slime
[ http://www.slimeland.com/ ]

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