RTL handling for ghost runs, NotoNaskhArabic test font (#8638)
diff --git a/third_party/txt/src/txt/paragraph.cc b/third_party/txt/src/txt/paragraph.cc
index 393b28b..01ced24 100644
--- a/third_party/txt/src/txt/paragraph.cc
+++ b/third_party/txt/src/txt/paragraph.cc
@@ -17,6 +17,8 @@
#include "paragraph.h"
#include <hb.h>
+#include <minikin/Layout.h>
+
#include <algorithm>
#include <limits>
#include <map>
@@ -24,7 +26,6 @@
#include <utility>
#include <vector>
-#include <minikin/Layout.h>
#include "flutter/fml/logging.h"
#include "font_collection.h"
#include "font_skia.h"
@@ -34,9 +35,6 @@
#include "minikin/LayoutUtils.h"
#include "minikin/LineBreaker.h"
#include "minikin/MinikinFont.h"
-#include "unicode/ubidi.h"
-#include "unicode/utf16.h"
-
#include "third_party/skia/include/core/SkCanvas.h"
#include "third_party/skia/include/core/SkFont.h"
#include "third_party/skia/include/core/SkFontMetrics.h"
@@ -46,6 +44,8 @@
#include "third_party/skia/include/core/SkTypeface.h"
#include "third_party/skia/include/effects/SkDashPathEffect.h"
#include "third_party/skia/include/effects/SkDiscretePathEffect.h"
+#include "unicode/ubidi.h"
+#include "unicode/utf16.h"
namespace txt {
namespace {
@@ -552,14 +552,8 @@
// Find the runs comprising this line.
std::vector<BidiRun> line_runs;
for (const BidiRun& bidi_run : bidi_runs) {
- if (bidi_run.start() < line_end_index &&
- bidi_run.end() > line_range.start) {
- line_runs.emplace_back(std::max(bidi_run.start(), line_range.start),
- std::min(bidi_run.end(), line_end_index),
- bidi_run.direction(), bidi_run.style());
- }
// A "ghost" run is a run that does not impact the layout, breaking,
- // alignment, width, etc but is still "visible" though getRectsForRange.
+ // alignment, width, etc but is still "visible" through getRectsForRange.
// For example, trailing whitespace on centered text can be scrolled
// through with the caret but will not wrap the line.
//
@@ -567,13 +561,30 @@
// let it impact metrics. After layout of the whitespace run, we do not
// add its width into the x-offset adjustment, effectively nullifying its
// impact on the layout.
+ std::unique_ptr<BidiRun> ghost_run = nullptr;
if (paragraph_style_.ellipsis.empty() &&
line_range.end_excluding_whitespace < line_range.end &&
bidi_run.start() <= line_range.end &&
bidi_run.end() > line_end_index) {
- line_runs.emplace_back(std::max(bidi_run.start(), line_end_index),
- std::min(bidi_run.end(), line_range.end),
- bidi_run.direction(), bidi_run.style(), true);
+ ghost_run = std::make_unique<BidiRun>(
+ std::max(bidi_run.start(), line_end_index),
+ std::min(bidi_run.end(), line_range.end), bidi_run.direction(),
+ bidi_run.style(), true);
+ }
+ // Include the ghost run before normal run if RTL
+ if (bidi_run.direction() == TextDirection::rtl && ghost_run != nullptr) {
+ line_runs.push_back(*ghost_run);
+ }
+ // Emplace a normal line run.
+ if (bidi_run.start() < line_end_index &&
+ bidi_run.end() > line_range.start) {
+ line_runs.emplace_back(std::max(bidi_run.start(), line_range.start),
+ std::min(bidi_run.end(), line_end_index),
+ bidi_run.direction(), bidi_run.style());
+ }
+ // Include the ghost run after normal run if LTR
+ if (bidi_run.direction() == TextDirection::ltr && ghost_run != nullptr) {
+ line_runs.push_back(*ghost_run);
}
}
bool line_runs_all_rtl =
@@ -661,6 +672,17 @@
if (layout.nGlyphs() == 0)
continue;
+ // When laying out RTL ghost runs, shift the run_x_offset here by the
+ // advance so that the ghost run is positioned to the left of the first
+ // real run of text in the line. However, since we do not want it to
+ // impact the layout of real text, this advance is subsequently added
+ // back into the run_x_offset after the ghost run positions have been
+ // calcuated and before the next real run of text is laid out, ensuring
+ // later runs are laid out in the same position as if there were no ghost
+ // run.
+ if (run.is_ghost() && run.is_rtl())
+ run_x_offset -= layout.getAdvance();
+
std::vector<float> layout_advances(text_count);
layout.getAdvances(layout_advances.data());
@@ -808,6 +830,7 @@
[](const GlyphPosition& a, const GlyphPosition& b) {
return a.code_units.start < b.code_units.start;
});
+
line_code_unit_runs.emplace_back(
std::move(code_unit_positions),
Range<size_t>(run.start(), run.end()),
@@ -815,14 +838,17 @@
glyph_positions.back().x_pos.end),
line_number, metrics, run.direction());
- min_left_ = std::min(min_left_, glyph_positions.front().x_pos.start);
- max_right_ = std::max(max_right_, glyph_positions.back().x_pos.end);
+ if (!run.is_ghost()) {
+ min_left_ = std::min(min_left_, glyph_positions.front().x_pos.start);
+ max_right_ = std::max(max_right_, glyph_positions.back().x_pos.end);
+ }
} // for each in glyph_blobs
-
- // Do not increase x offset for trailing ghost runs as it should not
- // impact the layout of visible glyphs. We do keep the record though so
- // GetRectsForRange() can find metrics for trailing spaces.
- if (!run.is_ghost()) {
+ // Do not increase x offset for LTR trailing ghost runs as it should not
+ // impact the layout of visible glyphs. RTL tailing ghost runs have the
+ // advance subtracted, so we do add the advance here to reset the
+ // run_x_offset. We do keep the record though so GetRectsForRange() can
+ // find metrics for trailing spaces.
+ if (!run.is_ghost() || run.is_rtl()) {
run_x_offset += layout.getAdvance();
}
} // for each in line_runs
diff --git a/third_party/txt/tests/paragraph_unittests.cc b/third_party/txt/tests/paragraph_unittests.cc
index bab5430..4be162d 100644
--- a/third_party/txt/tests/paragraph_unittests.cc
+++ b/third_party/txt/tests/paragraph_unittests.cc
@@ -706,6 +706,7 @@
txt::ParagraphStyle paragraph_style;
paragraph_style.max_lines = 14;
paragraph_style.text_align = TextAlign::justify;
+ paragraph_style.text_direction = TextDirection::rtl;
txt::ParagraphBuilder builder(paragraph_style, GetTestFontCollection());
txt::TextStyle text_style;
@@ -725,16 +726,33 @@
paragraph->Paint(GetCanvas(), 0, 0);
- ASSERT_TRUE(Snapshot());
-
auto glyph_line_width = [¶graph](int index) {
size_t second_to_last_position_index =
- paragraph->glyph_lines_[index].positions.size() - 2;
+ paragraph->glyph_lines_[index].positions.size() - 1;
return paragraph->glyph_lines_[index]
.positions[second_to_last_position_index]
.x_pos.end;
};
+ SkPaint paint;
+ paint.setStyle(SkPaint::kStroke_Style);
+ paint.setAntiAlias(true);
+ paint.setStrokeWidth(1);
+
+ // Tests for GetRectsForRange()
+ Paragraph::RectHeightStyle rect_height_style =
+ Paragraph::RectHeightStyle::kMax;
+ Paragraph::RectWidthStyle rect_width_style =
+ Paragraph::RectWidthStyle::kTight;
+ paint.setColor(SK_ColorRED);
+ std::vector<txt::Paragraph::TextBox> boxes =
+ paragraph->GetRectsForRange(0, 100, rect_height_style, rect_width_style);
+ for (size_t i = 0; i < boxes.size(); ++i) {
+ GetCanvas()->drawRect(boxes[i].rect, paint);
+ }
+ ASSERT_EQ(boxes.size(), 5ull);
+ ASSERT_TRUE(Snapshot());
+
// All lines except the last should be justified to the width of the
// paragraph.
for (size_t i = 0; i < paragraph->glyph_lines_.size() - 1; ++i) {
@@ -971,6 +989,74 @@
ASSERT_TRUE(Snapshot());
}
+// Checks if the rects are in the correct positions after typing spaces in
+// Arabic.
+TEST_F(ParagraphTest, DISABLE_ON_WINDOWS(ArabicRectsParagraph)) {
+ const char* text = "بمباركة التقليدية قام عن. تصفح يد ";
+ auto icu_text = icu::UnicodeString::fromUTF8(text);
+ std::u16string u16_text(icu_text.getBuffer(),
+ icu_text.getBuffer() + icu_text.length());
+
+ txt::ParagraphStyle paragraph_style;
+ paragraph_style.max_lines = 14;
+ paragraph_style.text_align = TextAlign::right;
+ paragraph_style.text_direction = TextDirection::rtl;
+ txt::ParagraphBuilder builder(paragraph_style, GetTestFontCollection());
+
+ txt::TextStyle text_style;
+ text_style.font_families = std::vector<std::string>(1, "Noto Naskh Arabic");
+ text_style.font_size = 26;
+ text_style.letter_spacing = 1;
+ text_style.word_spacing = 5;
+ text_style.color = SK_ColorBLACK;
+ text_style.height = 1;
+ text_style.decoration = TextDecoration::kUnderline;
+ text_style.decoration_color = SK_ColorBLACK;
+ builder.PushStyle(text_style);
+
+ builder.AddText(u16_text);
+
+ builder.Pop();
+
+ auto paragraph = builder.Build();
+ paragraph->Layout(GetTestCanvasWidth() - 100);
+
+ paragraph->Paint(GetCanvas(), 0, 0);
+
+ SkPaint paint;
+ paint.setStyle(SkPaint::kStroke_Style);
+ paint.setAntiAlias(true);
+ paint.setStrokeWidth(1);
+
+ // Tests for GetRectsForRange()
+ Paragraph::RectHeightStyle rect_height_style =
+ Paragraph::RectHeightStyle::kMax;
+ Paragraph::RectWidthStyle rect_width_style =
+ Paragraph::RectWidthStyle::kTight;
+ paint.setColor(SK_ColorRED);
+ std::vector<txt::Paragraph::TextBox> boxes =
+ paragraph->GetRectsForRange(0, 100, rect_height_style, rect_width_style);
+ for (size_t i = 0; i < boxes.size(); ++i) {
+ GetCanvas()->drawRect(boxes[i].rect, paint);
+ }
+ EXPECT_EQ(boxes.size(), 2ull);
+
+ EXPECT_FLOAT_EQ(boxes[0].rect.left(), 556.54688);
+ EXPECT_FLOAT_EQ(boxes[0].rect.top(), -0.26855469);
+ EXPECT_FLOAT_EQ(boxes[0].rect.right(), 900);
+ EXPECT_FLOAT_EQ(boxes[0].rect.bottom(), 44);
+
+ EXPECT_FLOAT_EQ(boxes[1].rect.left(), 510.09375);
+ EXPECT_FLOAT_EQ(boxes[1].rect.top(), -0.26855469);
+ EXPECT_FLOAT_EQ(boxes[1].rect.right(), 557.04688);
+ EXPECT_FLOAT_EQ(boxes[1].rect.bottom(), 44);
+
+ ASSERT_EQ(paragraph_style.text_align,
+ paragraph->GetParagraphStyle().text_align);
+
+ ASSERT_TRUE(Snapshot());
+}
+
TEST_F(ParagraphTest, GetGlyphPositionAtCoordinateParagraph) {
const char* text =
"12345 67890 12345 67890 12345 67890 12345 67890 12345 67890 12345 "
diff --git a/third_party/txt/third_party/fonts/NotoNaskhArabic-LICENSE.txt b/third_party/txt/third_party/fonts/NotoNaskhArabic-LICENSE.txt
new file mode 100644
index 0000000..d952d62
--- /dev/null
+++ b/third_party/txt/third_party/fonts/NotoNaskhArabic-LICENSE.txt
@@ -0,0 +1,92 @@
+This Font Software is licensed under the SIL Open Font License,
+Version 1.1.
+
+This license is copied below, and is also available with a FAQ at:
+http://scripts.sil.org/OFL
+
+-----------------------------------------------------------
+SIL OPEN FONT LICENSE Version 1.1 - 26 February 2007
+-----------------------------------------------------------
+
+PREAMBLE
+The goals of the Open Font License (OFL) are to stimulate worldwide
+development of collaborative font projects, to support the font
+creation efforts of academic and linguistic communities, and to
+provide a free and open framework in which fonts may be shared and
+improved in partnership with others.
+
+The OFL allows the licensed fonts to be used, studied, modified and
+redistributed freely as long as they are not sold by themselves. The
+fonts, including any derivative works, can be bundled, embedded,
+redistributed and/or sold with any software provided that any reserved
+names are not used by derivative works. The fonts and derivatives,
+however, cannot be released under any other type of license. The
+requirement for fonts to remain under this license does not apply to
+any document created using the fonts or their derivatives.
+
+DEFINITIONS
+"Font Software" refers to the set of files released by the Copyright
+Holder(s) under this license and clearly marked as such. This may
+include source files, build scripts and documentation.
+
+"Reserved Font Name" refers to any names specified as such after the
+copyright statement(s).
+
+"Original Version" refers to the collection of Font Software
+components as distributed by the Copyright Holder(s).
+
+"Modified Version" refers to any derivative made by adding to,
+deleting, or substituting -- in part or in whole -- any of the
+components of the Original Version, by changing formats or by porting
+the Font Software to a new environment.
+
+"Author" refers to any designer, engineer, programmer, technical
+writer or other person who contributed to the Font Software.
+
+PERMISSION & CONDITIONS
+Permission is hereby granted, free of charge, to any person obtaining
+a copy of the Font Software, to use, study, copy, merge, embed,
+modify, redistribute, and sell modified and unmodified copies of the
+Font Software, subject to the following conditions:
+
+1) Neither the Font Software nor any of its individual components, in
+Original or Modified Versions, may be sold by itself.
+
+2) Original or Modified Versions of the Font Software may be bundled,
+redistributed and/or sold with any software, provided that each copy
+contains the above copyright notice and this license. These can be
+included either as stand-alone text files, human-readable headers or
+in the appropriate machine-readable metadata fields within text or
+binary files as long as those fields can be easily viewed by the user.
+
+3) No Modified Version of the Font Software may use the Reserved Font
+Name(s) unless explicit written permission is granted by the
+corresponding Copyright Holder. This restriction only applies to the
+primary font name as presented to the users.
+
+4) The name(s) of the Copyright Holder(s) or the Author(s) of the Font
+Software shall not be used to promote, endorse or advertise any
+Modified Version, except to acknowledge the contribution(s) of the
+Copyright Holder(s) and the Author(s) or with their explicit written
+permission.
+
+5) The Font Software, modified or unmodified, in part or in whole,
+must be distributed entirely under this license, and must not be
+distributed under any other license. The requirement for fonts to
+remain under this license does not apply to any document created using
+the Font Software.
+
+TERMINATION
+This license becomes null and void if any of the above conditions are
+not met.
+
+DISCLAIMER
+THE FONT SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT
+OF COPYRIGHT, PATENT, TRADEMARK, OR OTHER RIGHT. IN NO EVENT SHALL THE
+COPYRIGHT HOLDER BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+INCLUDING ANY GENERAL, SPECIAL, INDIRECT, INCIDENTAL, OR CONSEQUENTIAL
+DAMAGES, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+FROM, OUT OF THE USE OR INABILITY TO USE THE FONT SOFTWARE OR FROM
+OTHER DEALINGS IN THE FONT SOFTWARE.
diff --git a/third_party/txt/third_party/fonts/NotoNaskhArabic-Regular.ttf b/third_party/txt/third_party/fonts/NotoNaskhArabic-Regular.ttf
new file mode 100644
index 0000000..ee6cdaa
--- /dev/null
+++ b/third_party/txt/third_party/fonts/NotoNaskhArabic-Regular.ttf
Binary files differ
