[cairo] Shouldn't Cairo use/offer degrees rather than radians?

David Kastrup dak at gnu.org
Wed Jul 5 20:03:35 UTC 2017

Andreas Lobinger <lobingera at gmail.com> writes:

> Hello colleague(s),
> i actually wanted to look closer on the example, unfortunately i
> cannot reproduce. This is a linux box, intel i3, ubuntu 14.04.

Intel Penryn (Core Duo) and Ubuntu 17.10 (to be) here.

> Can you explain further, how you decided for the y- coordinate?

Bisection: make the value smaller when the half circle did not touch the
border (like in your picture), make it larger when it did touch.

Eventually I reached a value where only one leg touched.  14.04 is a
long time ago: conceivable that there were changes in rasterization
since then.  Still I consider it rather likely that you'll find such a
half-touching value.

I did not try to automate this.

David Kastrup

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