Spline Sketchpad

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Using B-spline interpolation and approximation, this Demonstration turns your mouse's motion into smooth B-spline curves. Drag the pointer and release. The sketchpad takes care of the rest.


You can set color, opacity, and thickness for each curve. The other controls change global properties.

The higher the "approximation" slider value is, the smoother the resulting curves will be, but they will be less precise.


Contributed by: Yu-Sung Chang (March 2011)
Open content licensed under CC BY-NC-SA



In this Demonstration, least squares fitting is used to generate the approximate curves.

Higher-order approximation sometimes results in undesirable fitting, if given points are not smooth enough.

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