firka/flutter
3
0
Fork 1
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

libtxt: Restore code that had been disabled due to older versions of ICU and HarfBuzz (flutter/engine#4456)

Browse Source
This commit is contained in:
Jason Simmons
2017-12-14 09:43:59 -08:00
committed by GitHub
parent 99a8a731bb
commit 041deb64dc
2 changed files with 21 additions and 22 deletions
Download Patch File Download Diff File Expand all files Collapse all files

32
engine/src/flutter/third_party/txt/src/minikin/GraphemeBreak.cpp vendored
View File

@@ -113,8 +113,7 @@ bool GraphemeBreak::isGraphemeBreak(const float* advances,
return false;
}
// Rule GB9, x (Extend | ZWJ); Rule GB9a, x SpacingMark; Rule GB9b, Prepend x
// TODO(abarth): Add U_GCB_ZWJ once we update ICU.
if (p2 == U_GCB_EXTEND || /* p2 == U_GCB_ZWJ || */ p2 == U_GCB_SPACING_MARK ||
if (p2 == U_GCB_EXTEND || p2 == U_GCB_ZWJ || p2 == U_GCB_SPACING_MARK ||
p1 == U_GCB_PREPEND) {
return false;
}
@@ -158,25 +157,26 @@ bool GraphemeBreak::isGraphemeBreak(const float* advances,
}
}
// TODO(abarth): Enablet his code once we update ICU.
// Tailored version of Rule GB11, ZWJ × (Glue_After_Zwj | EBG)
// We try to make emoji sequences with ZWJ a single grapheme cluster, but only
// if they actually merge to one cluster. So we are more relaxed than the UAX
// #29 rules in accepting any emoji character after the ZWJ, but are tighter
// in that we only treat it as one cluster if a ligature is actually formed
// and we also require the character before the ZWJ to also be an emoji. if
// (p1 == U_GCB_ZWJ && isEmoji(c2) && offset_back > start) {
// // look at character before ZWJ to see that both can participate in an
// emoji zwj sequence uint32_t c0 = 0; size_t offset_backback =
// offset_back; U16_PREV(buf, start, offset_backback, c0); if (c0 ==
// 0xFE0F && offset_backback > start) {
// // skip over emoji variation selector
// U16_PREV(buf, start, offset_backback, c0);
// }
// if (isEmoji(c0)) {
// return false;
// }
// }
// and we also require the character before the ZWJ to also be an emoji.
if (p1 == U_GCB_ZWJ && isEmoji(c2) && offset_back > start) {
// look at character before ZWJ to see that both can participate in an
// emoji zwj sequence
uint32_t c0 = 0;
size_t offset_backback = offset_back;
U16_PREV(buf, start, offset_backback, c0);
if (c0 == 0xFE0F && offset_backback > start) {
// skip over emoji variation selector
U16_PREV(buf, start, offset_backback, c0);
}
if (isEmoji(c0)) {
return false;
}
}
// Tailored version of Rule GB12 and Rule GB13 that look at even-odd cases.
// sot (RI RI)* RI x RI

11
engine/src/flutter/third_party/txt/src/minikin/HbFontCache.cpp vendored
View File

@@ -103,12 +103,11 @@ hb_font_t* getHbFontLocked(const MinikinFont* minikinFont) {
hb_font_set_scale(parent_font, upem, upem);
font = hb_font_create_sub_font(parent_font);
// TODO(abarth): Enable this code once we update harfbuzz.
// std::vector<hb_variation_t> variations;
// for (const FontVariation& variation : minikinFont->GetAxes()) {
// variations.push_back({variation.axisTag, variation.value});
// }
// hb_font_set_variations(font, variations.data(), variations.size());
std::vector<hb_variation_t> variations;
for (const FontVariation& variation : minikinFont->GetAxes()) {
variations.push_back({variation.axisTag, variation.value});
}
hb_font_set_variations(font, variations.data(), variations.size());
hb_font_destroy(parent_font);
hb_face_destroy(face);
fontCache->put(fontId, font);