[cairo] Ellipse stroke

Richard Copley rcopley at gmail.com
Fri Nov 17 21:36:54 UTC 2017

On 17 November 2017 at 08:31, Richard Copley <rcopley at gmail.com> wrote:
> I'm not sure exactly what shaped path HTML5 Canvas creates
> for the strokes in the cases I illustrated.

Here's an HTML5 Canvas sample of some elliptical arcs:

I tried it on desktop Firefox, Chrome and Edge. Cairo's stroke has
undesirable gaps, in my opinion, and it breaks down when the minor
semiaxis is near zero. Webkit's stroke is like Cairo's but without the
problems when the minor semiaxis is near zero. Webkit strokes a simple
straight line when the minor semiaxis is equal to zero. Gecko's stroke
(using Skia) has desirable properties (no gaps!) and is the best, IMO.
Edge's stroke is kind of weird but not completely unusable.

BTW and hypothetically, could Cairo accept a patch it it were derived
from Mozilla's source code?

More information about the cairo mailing list