# Smooth Interpolating Curves with Local Control and Monotone Alternating Curvature

### Abstract

We propose a method for the construction of a planar curve based on piecewise clothoids and straight lines that intuitively interpolates a given sequence of control points. Our method has several desirable properties that are not simultaneously fulfilled by previous approaches: Our interpolating curves are $C^2$ continuous, their computation does not rely on global optimization and has local support, enabling fast evaluation for interactive modeling. Further, the sign of the curvature at control points is consistent with the control polygon; the curvature attains its extrema at control points and is monotone between consecutive control points of opposite curvature signs. In addition, we can ensure that the curve has self-intersections only when the control polygon also self-intersects between the same control points. For more fine-grained control, the user can specify the desired curvature and tangent values at certain control points, though it is not required by our method. Our local optimization can lead to discontinuity w.r.t. the locations of control points, although the problem is limited by its locality. We demonstrate the utility of our approach in generating various curves and provide a comparison with the state of the art.

Type
Publication
In EUROGRAPHICS Symposium on Geometry Processing 2022

## Talk

##### Comparison table
Trigonometric Blending $\kappa$-curves 3-arcs clothoid clothoid-line-clothoid
(Open images in a new tab to display the .svg properly)
##### Alexandre Binninger
###### Doctoral Student in Computer Science

My research interests include computer graphics, shape representations and interactive geometry.