vcl/source/font/FeatureCollector.cxx | 41 +++++++++++++++++++----------------
1 file changed, 23 insertions(+), 18 deletions(-)
New commits:
commit 3e544b6938ee509a4f6df4c2e2996d71ce072506
Author: Khaled Hosny <kha...@aliftype.com>
AuthorDate: Wed Aug 31 23:35:24 2022 +0200
Commit: خالد حسني <kha...@aliftype.com>
CommitDate: Thu Sep 1 00:33:20 2022 +0200
FeatureCollector: check for alternates only in GSUB
hb_ot_layout_lookup_get_glyph_alternates() does not take a table ta and
GSUB table is assumed, but if we are checking GPOS table then we will
passing a lookup index from a different table and the result will be
garbage (e.g. think Inter’s kern feature has 8 alternate glyphs).
Change-Id: I78d5eb8304aee3321f492d15e3fc10db47cdc628
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/139138
Tested-by: خالد حسني <kha...@aliftype.com>
Reviewed-by: خالد حسني <kha...@aliftype.com>
diff --git a/vcl/source/font/FeatureCollector.cxx
b/vcl/source/font/FeatureCollector.cxx
index 9430a7833e12..134462e0ed44 100644
--- a/vcl/source/font/FeatureCollector.cxx
+++ b/vcl/source/font/FeatureCollector.cxx
@@ -162,29 +162,34 @@ void FeatureCollector::collectForTable(hb_tag_t aTableTag)
}
}
- // Collect lookups in this feature, and input glyphs for each
- // lookup, and calculate the max number of alternates they have.
- unsigned int nLookups = hb_ot_layout_feature_get_lookups(
- m_pHbFace, aTableTag, nFeatureIdx, 0, nullptr, nullptr);
- std::vector<unsigned int> aLookups(nLookups);
- hb_ot_layout_feature_get_lookups(m_pHbFace, aTableTag,
nFeatureIdx, 0, &nLookups,
- aLookups.data());
unsigned int nAlternates = 0;
- hb_set_t* pGlyphs = hb_set_create();
- for (unsigned int nLookupIdx : aLookups)
+ if (aTableTag == HB_OT_TAG_GSUB)
{
- hb_set_clear(pGlyphs);
- hb_ot_layout_lookup_collect_glyphs(m_pHbFace, aTableTag,
nLookupIdx, nullptr,
- pGlyphs, nullptr, nullptr);
- hb_codepoint_t nGlyphIdx = HB_SET_VALUE_INVALID;
- while (hb_set_next(pGlyphs, &nGlyphIdx))
+ // Collect lookups in this feature, and input glyphs for each
+ // lookup, and calculate the max number of alternates they
have.
+ unsigned int nLookups = hb_ot_layout_feature_get_lookups(
+ m_pHbFace, aTableTag, nFeatureIdx, 0, nullptr, nullptr);
+ std::vector<unsigned int> aLookups(nLookups);
+ hb_ot_layout_feature_get_lookups(m_pHbFace, aTableTag,
nFeatureIdx, 0, &nLookups,
+ aLookups.data());
+
+ hb_set_t* pGlyphs = hb_set_create();
+ for (unsigned int nLookupIdx : aLookups)
{
- nAlternates = std::max(
- nAlternates, hb_ot_layout_lookup_get_glyph_alternates(
- m_pHbFace, nLookupIdx, nGlyphIdx, 0,
nullptr, nullptr));
+ hb_set_clear(pGlyphs);
+ hb_ot_layout_lookup_collect_glyphs(m_pHbFace, aTableTag,
nLookupIdx, nullptr,
+ pGlyphs, nullptr,
nullptr);
+ hb_codepoint_t nGlyphIdx = HB_SET_VALUE_INVALID;
+ while (hb_set_next(pGlyphs, &nGlyphIdx))
+ {
+ nAlternates
+ = std::max(nAlternates,
+
hb_ot_layout_lookup_get_glyph_alternates(
+ m_pHbFace, nLookupIdx, nGlyphIdx,
0, nullptr, nullptr));
+ }
}
+ hb_set_destroy(pGlyphs);
}
- hb_set_destroy(pGlyphs);
// Append the alternates to the feature parameters, keeping any
// existing ones calculated from cvXX features above.
