according to carl Worth, the Cairo developper, quadratic are easy to implement with cubic (the two cubic control points go 2/3 of the way toward the quadratic control point)
on another note, NavTeq has a patent on using circle arcs...
- Is this patentable? Is it patentable to use curves? I don't think so... --AndreR 16:59, 16 January 2008 (UTC)
- Is a circle arc the same thing as a Bezier curve? Bezier curves don't necessarily form circles. In fact, Wikipedia says they can't form exact circles. I think of a circle arc as having a center point, radius, and start/stop angles. --Elyk 05:22, 2 November 2008 (UTC)
It would be really useful to our app (X-Plane) to be able to have bezier-defined roads in OSM, available for export; it would mean a much better quality->data size. --Bsupnik 18:23, 31 October 2008 (UTC)
- If stupid apps don't support Bezier curves, I think it should be possible to convert the curve to a straight-line approximation before handing it off to the app. --Elyk 05:22, 2 November 2008 (UTC)
I'm wondering is there is anything you need that [2geom.org] doesn't already provide (if not, we want to know ;). Dual licence LGPL, MPL. In particular you might find the function cubics_fitting_curvature particularly useful - it finds the best cubic that meets two endpoints, given a direction and curvature at each endpoint. Makes very nice eased curves, very fast. Don't hesitate to contact the project with technical queries, we love a challenge. --Njh 06:16, 15 January 2009 (UTC)