> This is not correct. Normal hinting is intended for xppem = yppem. > Subpixel hinting, however, is a special mode to adjust hints in > TrueType fonts so that you get good rendering results for xppem = > 3*yppem, i.e., the resolution along the x axis is increased by a > factor of three.
> Regarding the `explosion', please read the beginning of Greg's > whitepaper on ClearType. > https://www.microsoft.com/typography/cleartype/truetypecleartype.aspx > Note that the new ClearType mode from Nikolaus has superseded the > Infinality mode (which was very slow and no longer actively > maintained). Just to clarify, when subpixel hinting is on, glyphs are hinted to full pixels in vertical direction, and horizontal hints are ignored [1] [1] https://www.freetype.org/freetype2/docs/subpixel-hinting.html 2017-03-27 7:49 GMT+02:00 Werner LEMBERG <[email protected]>: > >>> possible, be aware that some old fonts might `explode' in this >>> mode. >> >> Why would the old fonts "explode"? I thought the "subpixel hinting" >> was contributed from Infinality and it works best with modern fonts >> without good hinting. > > This is not correct. Normal hinting is intended for xppem = yppem. > Subpixel hinting, however, is a special mode to adjust hints in > TrueType fonts so that you get good rendering results for xppem = > 3*yppem, i.e., the resolution along the x axis is increased by a > factor of three. > > Regarding the `explosion', please read the beginning of Greg's > whitepaper on ClearType. > > https://www.microsoft.com/typography/cleartype/truetypecleartype.aspx > > Note that the new ClearType mode from Nikolaus has superseded the > Infinality mode (which was very slow and no longer actively > maintained). > >> Is it true that, without "subpixel hinting" FreeType2 will just hint >> fonts to "full pixels" which is exactly the scenario the old fonts >> was developed? > > Correct. > >> I think the fonts would look sharper that way. > > Good B/W hinting is *very* expensive to add to fonts since you have to > take care of the exact pixelation; there are just a handful of > well-paid experts who are doing that, and only a handful of fonts that > have such hints at all – mainly the screen fonts that come with > Windows XP and older. On the other hand, grayscale hinting can be > done quite well automatically (ttfautohint, VTT). > > To get `sharper' rendering you have to increase the sampling frequency > along the x axis; there are various possibilities how to do that. > FreeType's solution is, as mentioned above, to increase the horizontal > resolution, taking care of special situations that would yield to > wrong hinting. Microsoft's solution is super-sampling (which is the > superior approach IMHO), as explained in the whitepaper. > > > Werner > _______________________________________________ > Freetype mailing list > [email protected] > https://lists.nongnu.org/mailman/listinfo/freetype _______________________________________________ Freetype mailing list [email protected] https://lists.nongnu.org/mailman/listinfo/freetype
