Commit Graph

203 Commits

Author SHA1 Message Date
Behdad Esfahbod 59055b5494 [GX] Implement Feature Variations
Not hooked up to shaper yet.
2016-12-16 19:06:26 -06:00
Behdad Esfahbod 359dead960 Allow MultipleSubst to delete glyph
Fixes https://github.com/behdad/harfbuzz/issues/253

Hopefully we got the logic right.
2016-05-06 16:19:19 +01:00
Behdad Esfahbod 69f9fbc420 Synthesize GDEF glyph class for any glyph that does not have one in GDEF
Previously we only synthesized GDEF glyph classes if the glyphClassDef
array in GDEF was null.  This worked well enough, and is indeed what
OpenType requires: "If the font does not include a GlyphClassDef table,
the client must define and maintain this information when using the
GSUB and GPOS tables."  That sentence does not quite make sense since
one needs Unicode properties as well, but is close enough.

However, looks like Arial Unicode as shipped on WinXP, does have GDEF
glyph class array, but defines no classes for Hebrew.  This results
in Hebrew marks not getting their widths zeroed.  So, with this change,
we synthesize glyph class for any glyph that is not specified in the
GDEF glyph class table.  Since, from our point of view, a glyph not
being listed in that table is a font bug, any unwanted consequence of
this change is a font bug :).

Note that we still don't get the same rendering as Uniscribe, since
Uniscribe seems to do fallback positioning as well, even though the
font does have a GPOS table (which does NOT cover Hebrew!).  We are
not going to try to match that though.

Test string for Arial Unicode:

	U+05E9,U+05B8,U+05C1,U+05DC

Before:		[gid1166=3+991|gid1142=0+737|gid5798=0+1434]
After:		[gid1166=3+991|gid1142=0+0|gid5798=0+1434]
Uniscribe:	[gid1166=3+991|gid1142=0@348,0+0|gid5798=0+1434]

Note that our new output matches what we were generating until July
2014, because the Hebrew shaper used to zero mark advances based on
Unicode, NOT GDEF.  That's 9e834e29e0.

Reported by Greg Douglas.
2016-03-17 11:59:43 -07:00
Behdad Esfahbod 7d8d58ac81 [GPOS] Divide position_finish() into two phases, for advances and offsets
Right now the position_finish_advances() is empty.  To be used for
spacing attachments proposal later.
2016-02-11 16:34:28 +07:00
Behdad Esfahbod 5ba450407b Make max context-length and max nesting level configurable
...at compile time.
2015-11-02 15:43:39 -08:00
Behdad Esfahbod f396fbb000 Fix return value of sanitize when subformat is not readable
This is a fix on top of the previous issue fixed in
c917965b9e.

This was caught by "libFuzzer" testing.
2015-10-09 12:25:55 -04:00
Behdad Esfahbod b47159011c Define return_trace()
Not functional change (expected!).
2015-09-29 14:57:02 +01:00
Behdad Esfahbod c917965b9e Add missing returns
Fixes possible invalid read of two bytes.

Reported by Behzad Najjarpour Jabbari, Secunia Research.
2015-09-29 14:45:35 +01:00
Behdad Esfahbod 2c8b3b2e53 [debug] Print lookup index in debug-apply output 2015-08-18 14:36:43 +01:00
Behdad Esfahbod fc3c59a1d7 Fix unused var warnings 2015-04-08 13:04:29 -07:00
Behdad Esfahbod bd047d3b7f [layout] Minor 2015-02-25 15:43:31 -08:00
Behdad Esfahbod 1a2322134a [layout] Don't check glyph props against lookup flags when recursing
Shouldn't be needed.  I have a hard time imagining this breaking any
legitimate use case.
2015-02-25 15:43:30 -08:00
Behdad Esfahbod 095a1257cc [layout] Port sanitize() to use dispatch()
Needed some rework of Extension table.  Hopefully I got it right, and
the new template usage doesn't break any compilers...
2015-02-25 15:43:30 -08:00
Behdad Esfahbod 40c58923cb [layout] Refactor Lookup::dispatch() 2015-02-25 15:43:30 -08:00
Behdad Esfahbod 70366f5d19 [layout] Refactor get_subtable() 2015-02-25 15:43:29 -08:00
Behdad Esfahbod 8e36ccfd4f [layout] Use dispatch() for add_coverage() 2015-02-25 15:43:29 -08:00
Behdad Esfahbod 50b8dc79da [layout] Add may_dispatch()
No functional change right now.
2015-02-25 15:43:29 -08:00
Behdad Esfahbod de2118ed7a Make sanitize() a const method
This makes a lot of code safer.  We only try modifying the object in one
place, after making sure it's safe to do so.  So, do a const_cast<> in
that one place...
2015-02-25 15:43:28 -08:00
Behdad Esfahbod 6759ed95a3 Minor 2015-02-25 15:43:28 -08:00
Behdad Esfahbod 6b599dac1f Remove unnecessary check in sanitize 2015-02-25 15:43:28 -08:00
Behdad Esfahbod 7788993bc1 [layout] Use setter method to set c->lookup_props 2015-02-25 15:43:25 -08:00
Behdad Esfahbod 241eac9559 Hide internals of lookup accelerators 2015-02-25 15:43:25 -08:00
Behdad Esfahbod 00f6a8e334 [ot] Print format in dispatch trace 2014-12-12 20:36:49 -08:00
Behdad Esfahbod 5c87120b81 Fix misc warnings
Fixes https://github.com/behdad/harfbuzz/pull/51
2014-10-14 20:07:31 -07:00
Behdad Esfahbod 8f3eebf7ee Make sure gsubgpos buffer vars are available during fallback_position
Add buffer var allocation asserts to a few key places.
2014-08-02 19:07:49 -04:00
Behdad Esfahbod 7627100f42 Mark unsigned integer literals with the u suffix
Simplifies hb_in_range() calls as the type can be inferred.
The rest is obsessiveness, I admit.
2014-07-11 16:22:13 -04:00
Behdad Esfahbod 832a6f99b3 [indic] Don't reorder reph/pref if ligature was expanded
Normally if you want to, say, conditionally prevent a 'pref', you
would use blocking contextual matching.  Some designers instead
form the 'pref' form, then undo it in context.  To detect that
we now also remember glyphs that went through MultipleSubst.

In the only place that this is used, Uniscribe seems to only care
about the "last" transformation between Ligature and Multiple
substitions.  Ie. if you ligate, expand, and ligate again, it
moves the pref, but if you ligate and expand it doesn't.  That's
why we clear the MULTIPLIED bit when setting LIGATED.

Micro-test added.  Test: U+0D2F,0D4D,0D30 with font from:

[1]
https://code.google.com/a/google.com/p/noto-alpha/issues/detail?id=186#c29
2014-06-05 20:36:01 -04:00
Behdad Esfahbod b5be231720 [gsub] Adjust single-length ligature subst to act like single subst 2014-06-05 19:00:22 -04:00
Behdad Esfahbod aae69451df [gsub] Minor shuffling 2014-06-05 19:00:08 -04:00
Behdad Esfahbod b6b304f12b [ot] Add TODO re zero-len MultipleSubst sequences 2014-06-05 17:12:54 -04:00
Behdad Esfahbod 6faff8e413 Add static storage classifier to inline functions
Before we were just relying on the compiler inlining them and not
leaving a trace in our public API.  Try to fix.  Hopefully not
breaking anyone's build.
2014-04-28 14:30:44 -07:00
Behdad Esfahbod 333cc6e2d1 [otlayout] Remove unused is_inplace()
Patch from Jonathan Kew.
2013-10-30 17:30:11 +00:00
Behdad Esfahbod 101303dbf7 [otlayout] More shuffling around 2013-10-18 11:21:15 +02:00
Behdad Esfahbod 91689de260 [otlayout] Add _hb_glyph_info_set_glyph_props()
No functional change.
2013-10-18 11:21:15 +02:00
Behdad Esfahbod 3ddf892b53 [otlayout] Renaming 2013-10-18 11:21:15 +02:00
Behdad Esfahbod 03058c3d1e [otlayout] Remove two unused HB_OT_LAYOUT_GLYPH_PROPS_* values 2013-10-17 20:55:34 +02:00
Behdad Esfahbod 49901862e3 [otlayout] Guard against use of ReverseChain through Context 2013-10-17 19:48:51 +02:00
Behdad Esfahbod e714fe6d6a [otlayout] Simplify ligate_input()
Shouldn't change behavior at all, but is faster / more robust.
2013-10-17 13:49:51 +02:00
Behdad Esfahbod 6b65a76b40 [otlayout] Fix (Chain)Context recursion!
Previously we only supported recursive sublookups with
ascending indices.  We were also not correctly handling
non-1-to-1 recursed lookups.

Fix all that!

Fixes the three tests in test/shaping/tests/context-matching.tests,
which were derived from NotoSansBengali and NotoSansDevanagari
among others.
2013-10-14 18:54:51 +02:00
Behdad Esfahbod 6c48f20eea [otlayout] Add structs for JSTF table 2013-09-09 15:43:10 -04:00
Behdad Esfahbod 45f3d980c9 [OTLayout] Merge / templateize apply_string() 2013-05-04 16:04:04 -04:00
Behdad Esfahbod 780cd930a9 [OTLayout] Minor 2013-05-04 16:04:04 -04:00
Behdad Esfahbod 2e0c44f4be [OTLayout] Add is_inplace() method to GSUB 2013-05-04 16:04:04 -04:00
Behdad Esfahbod 5d59f99920 [OTLayout] Make MultipleSubst in-place for sequences of len=1 2013-05-02 15:39:16 -04:00
Behdad Esfahbod 54f84a6b85 [OTLayout] Whitespace 2013-05-02 15:39:16 -04:00
Behdad Esfahbod 0dc3a4e034 Obssesive optimization
Not measurable by any means, but conceptually this is faster since
the mask matches more often than the digest.
2013-04-17 23:04:03 -04:00
Behdad Esfahbod ee5464d17f [OTLayout] Move code around 2013-03-09 01:59:30 -05:00
Behdad Esfahbod 9c5a9ee967 [OTLayout] Rename process() to dispatch() 2013-03-09 01:55:04 -05:00
Behdad Esfahbod 99fa9ea020 Minor 2013-02-15 11:47:24 -05:00
Behdad Esfahbod 607feb7cff [OTLayout] Ignore default-ignorables when matching GSUB/GPOS
When matching lookups, be smart about default-ignorable characters.
In particular:

Do nothing specific about ZWNJ, but for the other default-ignorables:

If the lookup in question uses the ignorable character in a sequence,
then match it as we used to do.  However, if the sequence match will
fail because the default-ignorable blocked it, try skipping the
ignorable character and continue.

The most immediate thing it means is that if Lam-Alef forms a ligature,
then Lam-ZWJ-Alef will do to.  Finally!

One exception: when matching for GPOS, or for backtrack/lookahead of
GSUB, we ignore ZWNJ too.  That's the right thing to do.

It certainly is possible to build fonts that this feature will result
in undesirable glyphs, but it's hard to think of a real-world case
that that would happen.

This *does* break Indic shaping right now, since Indic Unicode has
specific rules for what ZWJ/ZWNJ mean, and skipping ZWJ is breaking
those rules.  That will be fixed in upcoming commits.
2013-02-14 12:57:50 -05:00
Behdad Esfahbod 407fc12466 [OTLayout] Remove bogus caching of glyph property 2013-02-13 11:13:06 -05:00
Behdad Esfahbod 8303593ba1 Minor
Use pointers instead of references, in preparation for upcoming change.
2012-12-04 17:08:41 -05:00
Behdad Esfahbod 3038ae6adb [OTLayout] Minor 2012-11-30 08:24:13 +02:00
Behdad Esfahbod b67881b171 [OTLayout] Remove operator() from Coverage 2012-11-24 19:13:55 -05:00
Behdad Esfahbod 4c4e8f0e75 [OTLayout] Reuse apply context for recursion 2012-11-24 01:13:20 -05:00
Behdad Esfahbod 26514d51b6 [OTLayout] More collect_glyphs() 2012-11-23 18:13:48 -05:00
Behdad Esfahbod c6fb843f2a [OTLayout] Templatize process_recurse_func 2012-11-23 18:04:08 -05:00
Behdad Esfahbod 9b34677f36 [OTLayout] Clean up closure() a bit 2012-11-23 17:55:40 -05:00
Behdad Esfahbod f48ec0e834 [OTLayout] Add process() tracing 2012-11-23 17:23:41 -05:00
Behdad Esfahbod ed2e135944 [OTLayout] More Extension templatizing 2012-11-23 17:10:40 -05:00
Behdad Esfahbod 7dddd4e72b [OTLayout] More templatizing Extension 2012-11-23 17:04:55 -05:00
Behdad Esfahbod 653eeb2645 Make Extension a template 2012-11-23 16:57:36 -05:00
Behdad Esfahbod 08f1eede1b Minor 2012-11-23 16:51:43 -05:00
Behdad Esfahbod be218c688c Pass this object to trace macros 2012-11-23 15:32:14 -05:00
Behdad Esfahbod c779d82b2f Fix warnings 2012-11-23 14:09:21 -05:00
Behdad Esfahbod ec35a72a44 [OTLayout] Port apply() operator to process() template 2012-11-22 16:33:46 -05:00
Behdad Esfahbod 2005fa5340 [OTLayout] Port would_apply() and get_coverage() to process() templates 2012-11-22 16:33:46 -05:00
Behdad Esfahbod 44fc237b53 [OTLayout] Port closure() to process() template 2012-11-22 16:33:46 -05:00
Behdad Esfahbod e8cfdd7fa8 Start implementing collect_glyphs() operation
Not functional yet.
2012-11-16 19:07:06 -08:00
Behdad Esfahbod 7d52e6601f Whitespace 2012-11-16 18:49:54 -08:00
Behdad Esfahbod 5a08ecf920 Implement hb_ot_layout_get_glyph_class() 2012-11-16 13:34:29 -08:00
Behdad Esfahbod 0bc7a38463 [OT] Fix ReverseChainingSubst
We should make it clear that we don't want output buffer in this case,
otherwise buffer->backtrack_len() would be wrong.
2012-10-29 22:02:45 -07:00
Behdad Esfahbod fabd3113a9 [OT] Port Arabic fallback shaping to synthetic GSUB
All of init/medi/fina/isol and rlig implemented.

Let there be dragons... ⻯
2012-09-06 00:51:44 -04:00
Behdad Esfahbod 1d3947a6bd Minor 2012-09-04 22:42:17 -04:00
Behdad Esfahbod b3b89b6658 [OT] Add SubstLookup serialize API 2012-09-04 21:28:33 -04:00
Behdad Esfahbod a930c68e9c [OT] More serialize. Implements all basic GSUB subtables 2012-09-04 19:16:09 -04:00
Behdad Esfahbod 1b38b4e817 Minor 2012-09-04 18:17:21 -04:00
Behdad Esfahbod 2bd9fe3598 Refactor 2012-09-04 15:15:19 -04:00
Behdad Esfahbod 2941683358 [OT] Implement serialize() for AlternateSubst 2012-09-03 23:31:14 -04:00
Behdad Esfahbod 1f07e3382a [OT] Implement serialize() for MultiSubst 2012-09-03 23:28:34 -04:00
Behdad Esfahbod 4912030dfb Minor 2012-09-03 21:00:48 -04:00
Behdad Esfahbod c61be03d6d [OT] A bit more serialize 2012-09-01 21:49:44 -04:00
Behdad Esfahbod abcc5ac1fd [OT] Improve serialize syntax
For some definition of improvement...
2012-09-01 21:30:17 -04:00
Behdad Esfahbod bc5be24014 [OT] Restart work on serialize() 2012-09-01 21:25:20 -04:00
Behdad Esfahbod 5e399a8a45 Minor 2012-08-29 10:40:49 -04:00
Behdad Esfahbod a177d027d1 [GSUB] Move ligation logic over 2012-08-28 23:18:22 -04:00
Behdad Esfahbod 191fa885d9 [GSUB] Merge Ligature and context input matching
Looks better now...
2012-08-28 22:58:55 -04:00
Behdad Esfahbod 93814ca7dc Start converging Ligature and match_input 2012-08-28 22:39:10 -04:00
Behdad Esfahbod 7c8e844d92 Use namespace for OpenType tables
Avoids USHORT, SHORT, ULONG, LONG clashes with Windows API.
2012-08-28 17:57:49 -04:00
Behdad Esfahbod 472f229a63 [GSUB] Generalize would_apply()
Fixes logic also, where before we were always matching if glyphs_len==1
and a ligature started with the glyph.
2012-08-07 22:25:24 -04:00
Behdad Esfahbod afbcc24be0 [GSUB] Wire the font, not just the face, down to substitute()
We need the font for glyph lookup during GSUB pauses in Indic shaper.
Could perhaps be avoided, but at this point, we don't mean to support
separate substitute()/position() entry points (anymore), so there is
no point in not providing the font to GSUB.
2012-08-02 08:36:40 -04:00
Behdad Esfahbod 22148b8c4a Use Coverage digests in would_apply 2012-08-02 03:51:51 -04:00
Behdad Esfahbod 6c459c8fef Minor 2012-08-02 03:45:53 -04:00
Behdad Esfahbod 0120ce9679 [GSUB/GPOS] Remove unused get_coverage() methods 2012-08-01 21:56:35 -04:00
Behdad Esfahbod 1336ecdf8e [GSUB/GPOS] Use Coverage digests as gatekeeper
Gives me a good 10% speedup for the Devanagari test case.  Less so
for less lookup-intensive tests.

For the Devanagari test case, the false positive rate of the GSUB digest
is 4%.
2012-08-01 21:46:36 -04:00
Behdad Esfahbod a878c58a8f [GSUB/GPOS] Add add_coverage() 2012-08-01 21:46:19 -04:00
Behdad Esfahbod 03b09214c0 [GSUB] Minor 2012-07-31 22:43:58 -04:00
Behdad Esfahbod c2e42c3db6 Minor 2012-07-30 19:54:50 -04:00
Behdad Esfahbod 03f67bc012 More refactoring glyph class access 2012-07-30 19:47:53 -04:00
Behdad Esfahbod 05bd1b6342 [GSUB/GPOS] Move glyph props matching around 2012-07-30 19:30:01 -04:00