[ft-devel] Peculiar Hinting / Rendering Behavior

[Darrell Bellert]

Greetings to the freetype community.

I am using freetype 2.5.0 and have encountered an interesting rendering 
artefact around hinting. I am using the Microsoft "MS Mincho Regular" 
true type typeface (msmincho.ttc) found with Windows 8:

ftview -m "四" -r 150 9 msmincho.ttc
(that's character 0x56db for the message)

When the viewer loads, do two things:
(1) Hit 'b' to turn embedded bitmap strikes OFF.
(2) Hit 'a' to turn anti-aliasing OFF

In my version of ftview, following these two steps results in the left 
vertical bar of the character to go missing. What I find to be rather 
interesting is that when I hit the 'h' key to turn hinting OFF in 
ftview, then the left vertical bar of the glyph returns!

My understanding of hinting is that it would do the opposite. In other 
words, turning hinting ON would enable better character generation.

Is this a problem in the font itself? A problem in freetype? Or is my 
understanding of hinting errant?

FWIW, forcing the autohinter on with the 'f' command will also correct 
the problem, but I can't use that in my code as I noticed that the 
autohinter tends to lighten some bold fonts at small resolutions, which 
for the moment is not desirable for me.

Thanks,

Darrell