FT_Get_Advances does not use the hdmx table
The hdmx
table is designed to accelerate the access to advances that are per-computed and stored for a few selected ppem sizes to avoid loading and hinting outlines. It is only useful for the v35 interpreter and less important for the modern hinting strategies with without horizontal hinting, and even illegal in variation fonts. Still, it seem to be an oversight not to use it in FT_Get_Advances
. At the first glance, this might be difficult to implement because the module get_advances
are used to returning unscaled values. We can probably make an exception for the hdmx
advances after specifically checking for the v35 engine (elseif of light).