Re: [ft-devel] [patch] emboldening rework v1

[Behdad Esfahbod]

On 04/18/2012 01:36 PM, Alexei Podtelezhnikov wrote:
> When we talk about an outline as a collection of contours, things get
> out of control very quickly, because to do a good job you have to
> inspect the whole layout of contours. For example the orientations of
> both contours is the same in "=" and different in "o". So we may rely

Actually no.  Now I guess *you* got confused the same way that I got!  In '=',
each contour can have whatever direction it wants.  Non-zero winding renders
all four possibilities fine.

> on EITHER the orientation of the contour with the largest area OR the
> the sum of all contour areas.
> 
> So here is my simple suggestion. Return NONE when the orientation
> according to the the largest contour is not the same as the
> orientation according to the sum of all.

This will result in false positives, and that's bad.

> Thoughts? Once again, the current implementation is broken so it is
> not like we need to care about backwards compatibility.

It isn't impossible to detect the direction of all outer contours, but is much
more involved than your signed-area-based algorithm indeed.

Perhaps the question to be answered is, is anyone using that API right now?

behdad