<div dir="ltr">The rendering is separate from harfbuzz i thought, the glyphs get passed to cairo’s cr.show_glyphs() and it uses its own font structure that has to be loaded separately from harfbuzz’s fonts. So any value set on the harfbuzz font is not known by the renderer </div><div class="gmail_extra"> <div class="gmail_quote">On Tue, Jun 28, 2016 at 7:48 PM, Khaled Hosny <<a href="mailto:khaledhosny@eglug.org" target="_blank">khaledhosny@eglug.org</a>> wrote: <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">For device tables (as I said in my first reply) and I think hinting (though I don’t think hinting stuff affects HarfBuzz right now). <div class="HOEnZb"><div class="h5"> On Tue, Jun 28, 2016 at 07:25:27PM -0400, Kelvin Ma wrote: > ok this might be a dumb question but what is ppem used for anyway? I > thought it was a font value that harfbuzz just lets you read off of the > font (like upem, advance width, or glyph index) so you can do your own math > on the font outside of harfbuzz. > > On Tue, Jun 28, 2016 at 7:18 PM, Khaled Hosny <<a href="mailto:khaledhosny@eglug.org">khaledhosny@eglug.org</a>> wrote: > > > It is, but you have to set it separately, and then you can set the font > > scale to whatever value you need without both being interdependent. > > > > On Tue, Jun 28, 2016 at 07:15:23PM -0400, Kelvin Ma wrote: > > > I thought ppem was dependent on UPEM and font scale, is it not? > > > > > > On Tue, Jun 28, 2016 at 7:12 PM, Khaled Hosny <<a href="mailto:khaledhosny@eglug.org">khaledhosny@eglug.org</a>> > > wrote: > > > > > > > Device tables depend on ppem, so despite the scale being set > > > > on the font, you should still set the exact ppem. > > > > > > > > On Tue, Jun 28, 2016 at 06:43:58PM -0400, Kelvin Ma wrote: > > > > > so that’s the only way huh… > > > > > doesn’t that kind of defeat the purpose of hb.font_create() and > > having > > > > many > > > > > scaled versions of the same font? You would only ever need one font > > of > > > > each > > > > > face, scaled to the UPEM, if the fontsize was to be applied > > externally > > > > > after shaping already occurred. > > > > > > > > > > On Tue, Jun 28, 2016 at 5:51 PM, Behdad Esfahbod <<a href="mailto:behdad@behdad.org">behdad@behdad.org</a>> > > > > wrote: > > > > > > > > > > > HarfBuzz coordinates work in a int32 space. You are free to set > > > > whatever > > > > > > scales you want on the font. For example, use 6 or 8 or 10 or 16 > > bits > > > > of > > > > > > sub-pixel precision by multiplying your scale by a number. > > > > > > > > > > > > On Tue, Jun 28, 2016 at 4:57 PM, Kelvin Ma < > > <a href="mailto:kelvinsthirteen@gmail.com">kelvinsthirteen@gmail.com</a>> > > > > > > wrote: > > > > > > > > > > > >> It appears that harfbuzz rounds all decimals to integers when > > giving > > > > > >> glyph advances and offsets. This is causing some ugly misalignment > > > > problems > > > > > >> in arabic shaping, as well as latin cursive fonts. (see pictures) > > > > > >> > > > > > >> [image: Inline image 1] > > > > > >> > > > > > >> [image: Inline image 2] > > > > > >> > > > > > >> [image: Inline image 3] > > > > > >> How do I get harfbuzz to preserve the floats? > > > > > >> > > > > > >> _______________________________________________ > > > > > >> HarfBuzz mailing list > > > > > >> <a href="mailto:HarfBuzz@lists.freedesktop.org">HarfBuzz@lists.freedesktop.org</a> > > > > > >> <a href="https://lists.freedesktop.org/mailman/listinfo/harfbuzz" rel="noreferrer" target="_blank">https://lists.freedesktop.org/mailman/listinfo/harfbuzz</a> > > > > > >> > > > > > >> > > > > > > > > > > > > > > > > > > -- > > > > > > behdad > > > > > > <a href="http://behdad.org/" rel="noreferrer" target="_blank">http://behdad.org/</a> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > _______________________________________________ > > > > > HarfBuzz mailing list > > > > > <a href="mailto:HarfBuzz@lists.freedesktop.org">HarfBuzz@lists.freedesktop.org</a> > > > > > <a href="https://lists.freedesktop.org/mailman/listinfo/harfbuzz" rel="noreferrer" target="_blank">https://lists.freedesktop.org/mailman/listinfo/harfbuzz</a> > > > > > > > > > > </div></div></blockquote></div> </div>