226288 - freetype code uses ceiling when rounding is better

Status: RESOLVED FIXED

(Core Graveyard :: GFX: Gtk, defect)

Description

[Jungshik Shin]

spun off from bug 222920.

dbaron found that freetype library itself uses rounding whenever it wants to
convert 'design' units to pixels and fixed it in nsFontMetricsXft. We have to
fix it in nsFreetype.cpp as well. It uses ceiling in several places. 



FT_CEIL used there is defined here (I think I copied MOZ_FT_CEILING from here):

http://lxr.mozilla.org/seamonkey/source/gfx/idl/nsIFreeType2.idl#51

Comment 1

[Jungshik Shin]

Attachment: a patch

In addition to fixing the bug, I changed the dummy functions for superscript
offset/subscript offset to do the real job by reading values from the OS/2
table.

Comment 2

[Jungshik Shin]

Comment on attachment 136731 [details] [diff] [review]
a patch

asking for r/sr.
this is a straightforward application of what's done in Xft to FT2/PS code.

Comment 3

[Jungshik Shin]

dbaron, can you review?

Comment 4

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

Comment on attachment 136731 [details] [diff] [review]
a patch

r=dbaron, although I think it would be cleaner if both implementations of
max_ascent and max_descent used the same macro that everything else did (which
wouldn't be hard -- just factor out the FT_MulFix call).

Comment 5

[rbs]

Comment on attachment 136731 [details] [diff] [review]
a patch

sr=rbs, I agree with the simplification requested above.

Comment 6

[Jungshik Shin]

thanks. fix checked (with the simplication suggested by dbaron) into the trunk.
I just came up with an idea to get rid of the code duplication in
nsFontFreeType.cpp and nsFontMtericsPS.cpp. I should have done it here. I'll
deal with it in another bug.