[HarfBuzz] Can't map characters to glyphInfos using clusters

[Khaled Hosny]

> On Mar 4, 2020, at 12:08 AM, bo samson <bo.samson at gmail.com> wrote:
> 
> Hi all,
> When rendering each of my glyphs, I'd like to know if there are, for example, linebreaks, so that I can skip them and go to the next line. (or at the very least, skip that character)
> 
> According to the documentation, I should be using the glyphinfo.cluster for this, but this info is unusable, even in ClusterLevel 2. The cluster number will even increment past the length of my string. 

The cluster is input string code units (if you use add_utf* functions), so if your input is UTF-8 string it will be in bytes.

Regards,
Khaled