[ft-devel] [PATCH] CJK Autohinter should not clump stems together when there are too many of them

[r6144]

Hello,

Some Chinese characters, such as 量 and 置, have a large number of
horizontal stems.  At ordinary sizes, the autohinter will often clump
adjacent stems together; although the result remains readable, the
unevenness of black and white looks rather ugly.

afcjk.patch is my patch that attempts to solve this problem.  All stems
that are pixel-aligned have at least one pixel of space (or other stems)
in between.  Other stems are not aligned, but only have their position
interpolated, so they have the un-hinted look which is IMHO better.

orig.png and new.png compares the rendered result without and with this
patch, for WenQuanYi MicroHei at 15px with slight autohinting.  I think
new.png looks noticeably better than orig.png, and better than no
hinting as well.  That font is now quite comfortable to read down to
about 12px.

The entire tree currently used by myself is at:
https://github.com/r6144/freetype2/tree/infinality-my-adjustment

Please CC me as I'm not subscribed.

r6144

afcjk.patch
Description: Text Data

orig.png
Description: PNG image

new.png
Description: PNG image