Spline Sketchpad
Spline Sketchpad
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.