[HarfBuzz] HarfBuzz glyph offsets

[Khaled Hosny]

On Wed, Dec 23, 2015 at 03:20:10PM -0800, Jonathan Blow wrote:
> >
> >
> >
> > You don't need to look into bearings metrics if you want to render
> > something. And no, they are not offsets.
> >
> > HB gives you advances and offset vectors. So what you need to do is:
> >
> > (origin) -> (render glyph at origin+offset) -> (move origin by advance)
> > -> repeat.
> >
> 
> ​I guess the point of confusion is what does "render glyph" mean in your
> flowchart here. I am not able to conceive of any version of "render glyph"
> whose implementation does not involve adding horiBearingX, which is why I
> wonder if you guys are thinking about it as calling some API call that
> people commonly presume but which is not what is going on in my case.
> ​

The problem is that you are mixing “render glyph” internal with the rest
of this flow chart. How you render a glyph is up to what font rendering
API you use, just don’t mix it with how the glyph origin is placed.

Regards,
Khaled