Akima spline curves give drawing freedom, at least some kind of interpolating
spline curve where you can just simply lay the points down and the curve
follows along the points - I have a hard time getting bezier curves to do what
I want. It's like Alice in wonderland using a flamingo for a mallet in a game
of croquet. unweildly.
Bezier Curves were introduced into Windows NT. It seems like a lot of paint
programs began including Bezier Curves as a drawing method after that.
They should have also introduced Akima spline curves into Windows. I am not
saying take Bezier curves out - I am saying Add Akima Spline curves, or the
bettered (modified) version of Akima Spline curves that doesn't react as much.
At least some type of interpolating spline curve where you just lay the points
down and the curve follows the points.
Akima spline curves are cool. just put points along where you want the curve.
simple. you just need more points around sharp edges, or you get a "ringing"
effect around that area. (See discussion and visuals link).
part of the challenge of using Akima spline curves is that the first 2 data
points must be faked or dropped. same goes with the last data point. this can
be taken care of with some simple engineering tricks.
Wikipedia article on Spline curves (mathematics). This does not cover the Akima
keeps its curve along the data points rather than just near it like a B-spline
demonstration of the various curve types in action. (requires Java) play with
the spline curve for
a while (delete the existing points other than 0 first to get started)
B-Spline curve with Knots (can be active demo)
GNU Scientific Library Reference Manual
book - has Akima Spline & Cubic Spline. See also
PDF file from medical site on akima and spline methods and its associated
for fixing the significant overshoot on abrupt changes, and suggestion to use
more closely spaced
points around those regions. must purchase.
The Akima Univariate Interpolation Method (spline) article from the acm. by
requires web account and probably money to buy the PDF article.
Equations for Akima Spline
http://www.alglib.net/interpolation/spline3.phpdiscussion and visuals of Akima
Spline and its
drawbacks. also has source code in C++, C#, Delphi, VB6, Zonnon.
pay-for article on some sort of improved-smoothness spline. Shape of data is
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