Download:

Paper (PDF, ~1.6 MB)
Video (DivX, ~2.5 MB)
Demo (Win32, ~400 kB)
Source (C++, ~4 MB. Includes VS2008 project file. Library dependencies: OpenGL, GLUT, GLUI, DevIL.)

(March 11, 2010) Update!

I have put up a new demo and source code demonstrating the convergent method to close curves. Also, I put in code to get eigenvalues and do linear regression within the ClothoidSpline class explicitly, removing the dependency to the WildMagic library. Added links to video and slides from SBIM 2008 presentation.

Overview:

A paper I presented at the Fifth Eurographics Conference on Sketch-Based Interfaces and Modeling 2008, which received one of four "best paper" awards of 23 submissions. In short, the paper details an approach to fitting a piecewise clothoid curve to an input polyline. The approach is ideal for applications where stroke fairness takes precedence over precise interpolation of points.