1 Department of Mathematics, Technical University of Denmark2 Department of Applied Mathematics and Computer Science, Technical University of Denmark
This paper presents the intrinsic equation of a planar curve as a practical tool for curve design. It is demonstrated that the tangent direction, the arc length, and the curvature is readily available. It is furthermore shown that a parametrization of the curve by tangent direction is easily obtained, as are the evolute, the involutes and the offsets. It is finally shown how Hermite data can be fitted in a local and convexity preserving way.