Jon - On Wed, Jul 10, 2019 at 01:29:11PM -0400, Jon Evans wrote: > I am curious why start-midpoint-end is better than start-center-end, though. > I think the latter is used more often in mcad tools, although I could be > wrong.
start-center-end is mathematically over-constrained, so it sounds worth avoiding. start-midpoint-end encodes a useless -- but not over-constrining -- degree of freedom, in the position along the arc of the "midpoint". The mathematically correct number of parameters is five, and Seth makes a good case that four of them should be the start and end coordinates. One non-pathological definition of the fifth parameter is curvature, in units of inverse-distance. Zero is no curvature -- converts back to a straight line. The sign of the curvature tells whether the arc bends left or right. I _don't_ assert that this is any better in real life than start-midpoint-end. - Larry _______________________________________________ Mailing list: https://launchpad.net/~kicad-developers Post to : kicad-developers@lists.launchpad.net Unsubscribe : https://launchpad.net/~kicad-developers More help : https://help.launchpad.net/ListHelp
