[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [ft-devel] Hinting paths

From: Nikolaus Waxweiler
Subject: Re: [ft-devel] Hinting paths
Date: Mon, 2 Nov 2015 23:35:00 +0100
User-agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.3.0

One peculiarity to note: If in `native ClearType' mode, a modification
of a glyph's advance width is properly executed by the MS hinter.
However, the MS rasterizer ignores it, always using linear advance
widths in modern Windows versions.  Previous versions supported a
`compatible-width ClearType' mode (cf. selector bit 7 in the GETINFO
instruction).  Unfortunately, there is no way currently to circumvent

So that's where the different advances between GDI and DirectWrite come from? :)

Yes.  Backwards-compatibility mode is essential to hint older fonts,
or fonts that are written to use the same bytecode for both ClearType
and non-ClearType, relying on the fact that (most) instructions along
the horizontal axis are ignored.

And that mode is hidden behind the SUBPIXEL_HINTING define? What's the difficulty in leaving out horizontal instructions?

Example, please, ideally translated to key sequences that I can use
with ftview.

Hm, I couldn't reproduce the differences between autohint off medium and full (reset my conf.d to mostly defaults yesterday, might have been some spurious interaction with 10-autohint.conf or something?). However, the difference between autohint on medium and full is still there: (full-noauto, full-auto, medium-auto). Not sure about the key strokes, according to cairo source, both medium and full should lead to FT_LOAD_TARGET_LCD(_V) and autohint should result in an additional FT_LOAD_FORCE_AUTOHINT. Dunno.

reply via email to

[Prev in Thread] Current Thread [Next in Thread]