blob: 63d9d9fbd5acbdf264d5d6a04262ddbb2eefb74d [file] [log] [blame]
// Copyright 2021 Google LLC.
#include "experimental/sktext/include/Text.h"
#include "experimental/sktext/src/LogicalRun.h"
#include "experimental/sktext/src/VisualRun.h"
#include <memory>
#include <stack>
namespace skia {
namespace text {
UnicodeText::UnicodeText(std::unique_ptr<SkUnicode> unicode, SkSpan<uint16_t> utf16)
: fText16(std::u16string((char16_t*)utf16.data(), utf16.size()))
, fUnicode(std::move(unicode)) {
initialize(utf16);
}
UnicodeText::UnicodeText(std::unique_ptr<SkUnicode> unicode, const SkString& utf8)
: fUnicode(std::move(unicode)) {
fText16 = fUnicode->convertUtf8ToUtf16(utf8);
initialize(SkSpan<uint16_t>((uint16_t*)fText16.data(), fText16.size()));
}
bool UnicodeText::isWhitespaces(TextRange range) const {
for (auto i = range.fStart; i < range.fEnd; ++i) {
if (!this->hasProperty(i, CodeUnitFlags::kPartOfWhiteSpace)) {
return false;
}
}
return true;
}
void UnicodeText::initialize(SkSpan<uint16_t> utf16) {
if (!fUnicode) {
SkASSERT(fUnicode);
return;
}
// Get white spaces
fCodeUnitProperties.push_back_n(utf16.size() + 1, CodeUnitFlags::kNoCodeUnitFlag);
this->fUnicode->forEachCodepoint((char16_t*)utf16.data(), utf16.size(),
[this](SkUnichar unichar, int32_t start, int32_t end) {
if (this->fUnicode->isWhitespace(unichar)) {
for (auto i = start; i < end; ++i) {
fCodeUnitProperties[i] |= CodeUnitFlags::kPartOfWhiteSpace;
}
}
});
// Get graphemes
this->fUnicode->forEachBreak((char16_t*)utf16.data(), utf16.size(), SkUnicode::BreakType::kGraphemes,
[this](SkBreakIterator::Position pos, SkBreakIterator::Status) {
fCodeUnitProperties[pos]|= CodeUnitFlags::kGraphemeStart;
});
// Get line breaks
this->fUnicode->forEachBreak((char16_t*)utf16.data(), utf16.size(), SkUnicode::BreakType::kLines,
[this](SkBreakIterator::Position pos, SkBreakIterator::Status status) {
if (status == (SkBreakIterator::Status)SkUnicode::LineBreakType::kHardLineBreak) {
// Hard line breaks clears off all the other flags
// TODO: Treat \n as a formatting mark and do not pass it to SkShaper
fCodeUnitProperties[pos - 1] = CodeUnitFlags::kHardLineBreakBefore;
} else {
fCodeUnitProperties[pos] |= CodeUnitFlags::kSoftLineBreakBefore;
}
});
}
std::unique_ptr<FontResolvedText> UnicodeText::resolveFonts(SkSpan<FontBlock> blocks) {
auto fontResolvedText = std::make_unique<FontResolvedText>();
TextRange adjustedBlock(0, 0);
TextIndex index = 0;
for (auto& block : blocks) {
index += block.charCount;
adjustedBlock.fStart = adjustedBlock.fEnd;
adjustedBlock.fEnd = index;
if (adjustedBlock.fStart >= adjustedBlock.fEnd) {
// The last block adjustment went over the entire block
continue;
}
// Move the end of the block to the right until it's on the grapheme edge
while (adjustedBlock.fEnd < this->fText16.size() && !this->hasProperty(adjustedBlock.fEnd, CodeUnitFlags::kGraphemeStart)) {
++adjustedBlock.fEnd;
}
SkASSERT(block.type == BlockType::kFontChain);
fontResolvedText->resolveChain(this, adjustedBlock, *block.chain);
}
std::sort(fontResolvedText->fResolvedFonts.begin(), fontResolvedText->fResolvedFonts.end(),
[](const ResolvedFontBlock& a, const ResolvedFontBlock& b) {
return a.textRange.fStart < b.textRange.fStart;
});
/*
SkDebugf("Resolved:\n");
for (auto& f : fontResolvedText->fResolvedFonts) {
SkDebugf("[%d:%d)\n", f.textRange.fStart, f.textRange.fEnd);
}
*/
return std::move(fontResolvedText);
}
bool FontResolvedText::resolveChain(UnicodeText* unicodeText, TextRange textRange, const FontChain& fontChain) {
std::deque<TextRange> unresolvedTexts;
unresolvedTexts.push_back(textRange);
for (auto fontIndex = 0; fontIndex < fontChain.count(); ++fontIndex) {
auto typeface = fontChain[fontIndex];
std::deque<TextRange> newUnresolvedTexts;
// Check all text range that have not been resolved yet
while (!unresolvedTexts.empty()) {
// Take the first unresolved
auto unresolvedText = unresolvedTexts.front();
unresolvedTexts.pop_front();
// Resolve font for the entire grapheme
auto start = newUnresolvedTexts.size();
unicodeText->forEachGrapheme(unresolvedText, [&](TextRange grapheme) {
auto count = typeface->textToGlyphs(unicodeText->getText16().data() + grapheme.fStart, grapheme.width() * 2, SkTextEncoding::kUTF16, nullptr, 0);
SkAutoTArray<SkGlyphID> glyphs(count);
typeface->textToGlyphs(unicodeText->getText16().data() + grapheme.fStart, grapheme.width() * 2, SkTextEncoding::kUTF16, glyphs.data(), count);
for (auto i = 0; i < count; ++i) {
if (glyphs[i] == 0) {
if (newUnresolvedTexts.empty() || newUnresolvedTexts.back().fEnd < grapheme.fStart) {
// It's a new unresolved block
newUnresolvedTexts.push_back(grapheme);
} else {
// Let's extend the last unresolved block
newUnresolvedTexts.back().fEnd = grapheme.fEnd;
}
break;
}
}
});
// Let's fill the resolved blocks with the current font
TextRange resolvedText(unresolvedText.fStart, unresolvedText.fStart);
for (auto newUnresolvedText : newUnresolvedTexts) {
if (start > 0) {
--start;
continue;
}
resolvedText.fEnd = newUnresolvedText.fStart;
if (resolvedText.width() > 0) {
// Add another resolved block
fResolvedFonts.emplace_back(resolvedText, typeface, fontChain.fontSize(), SkFontStyle::Normal());
}
resolvedText.fStart = newUnresolvedText.fEnd;
}
resolvedText.fEnd = unresolvedText.fEnd;
if (resolvedText.width() > 0) {
// Add the last resolved block
fResolvedFonts.emplace_back(resolvedText, typeface, fontChain.fontSize(), SkFontStyle::Normal());
}
}
// Try the next font in chain
SkASSERT(unresolvedTexts.empty());
unresolvedTexts = std::move(newUnresolvedTexts);
}
return unresolvedTexts.empty();
}
// Font iterator that finds all formatting marks
// and breaks runs on them (so we can select and interpret them later)
class FormattingFontIterator final : public SkShaper::FontRunIterator {
public:
FormattingFontIterator(TextIndex textCount,
SkSpan<ResolvedFontBlock> fontBlocks,
SkSpan<TextIndex> marks)
: fTextCount(textCount)
, fFontBlocks(fontBlocks)
, fFormattingMarks(marks)
, fCurrentBlock(fontBlocks.begin())
, fCurrentMark(marks.begin())
, fCurrentFontIndex(fCurrentBlock->textRange.fEnd) {
fCurrentFont = this->createFont(*fCurrentBlock);
}
void consume() override {
SkASSERT(fCurrentBlock < fFontBlocks.end());
SkASSERT(fCurrentMark < fFormattingMarks.end());
if (fCurrentFontIndex > *fCurrentMark) {
++fCurrentMark;
return;
}
if (fCurrentFontIndex == *fCurrentMark) {
++fCurrentMark;
}
++fCurrentBlock;
if (fCurrentBlock < fFontBlocks.end()) {
fCurrentFontIndex = fCurrentBlock->textRange.fEnd;
fCurrentFont = this->createFont(*fCurrentBlock);
}
}
size_t endOfCurrentRun() const override {
SkASSERT(fCurrentMark != fFormattingMarks.end() || fCurrentBlock != fFontBlocks.end());
if (fCurrentMark == fFormattingMarks.end()) {
return fCurrentFontIndex;
} else if (fCurrentBlock == fFontBlocks.end()) {
return *fCurrentMark;
} else {
return std::min(fCurrentFontIndex, *fCurrentMark);
}
}
bool atEnd() const override {
return (fCurrentBlock == fFontBlocks.end() || fCurrentFontIndex == fTextCount) &&
(fCurrentMark == fFormattingMarks.end() || *fCurrentMark == fTextCount);
}
const SkFont& currentFont() const override { return fCurrentFont; }
SkFont createFont(const ResolvedFontBlock& resolvedFont) const {
SkFont font(resolvedFont.typeface, resolvedFont.size);
font.setEdging(SkFont::Edging::kAntiAlias);
font.setHinting(SkFontHinting::kSlight);
font.setSubpixel(true);
return font;
}
private:
TextIndex const fTextCount;
SkSpan<ResolvedFontBlock> fFontBlocks;
SkSpan<TextIndex> fFormattingMarks;
ResolvedFontBlock* fCurrentBlock;
TextIndex* fCurrentMark;
TextIndex fCurrentFontIndex;
SkFont fCurrentFont;
};
std::unique_ptr<ShapedText> FontResolvedText::shape(UnicodeText* unicodeText,
TextDirection textDirection) {
// Get utf8 <-> utf16 conversion tables.
// We need to pass to SkShaper indices in utf8 and then convert them back to utf16 for SkText
auto text16 = unicodeText->getText16();
auto text8 = SkUnicode::convertUtf16ToUtf8(std::u16string(text16.data(), text16.size()));
size_t utf16Index = 0;
SkTArray<size_t, true> UTF16FromUTF8;
SkTArray<size_t, true> UTF8FromUTF16;
UTF16FromUTF8.push_back_n(text8.size() + 1, utf16Index);
UTF8FromUTF16.push_back_n(text16.size() + 1, utf16Index);
unicodeText->getUnicode()->forEachCodepoint(text8.c_str(), text8.size(),
[&](SkUnichar unichar, int32_t start, int32_t end, int32_t count) {
// utf8 index group of 1, 2 or 3 can be represented with one utf16 index group
for (auto i = start; i < end; ++i) {
UTF16FromUTF8[i] = utf16Index;
}
// utf16 index group of 1 or 2 can refer to the same group of utf8 indices
for (; count != 0; --count) {
UTF8FromUTF16[utf16Index++] = start;
}
});
UTF16FromUTF8[text8.size()] = text16.size();
UTF8FromUTF16[text16.size()] = text8.size();
// Break text into pieces by font blocks and by formatting marks
// Formatting marks: \n (and possibly some other later)
std::vector<size_t> formattingMarks;
for (size_t i = 0; i < text16.size(); ++i) {
if (unicodeText->isHardLineBreak(i)) {
formattingMarks.emplace_back(UTF8FromUTF16[i]);
formattingMarks.emplace_back(UTF8FromUTF16[i + 1]);
++i;
}
}
formattingMarks.emplace_back(text8.size()/* UTF8FromUTF16[text16.size() */);
// Convert fontBlocks from utf16 to utf8
SkTArray<ResolvedFontBlock, true> fontBlocks8;
TextIndex index8 = 0;
for (auto& fb : fResolvedFonts) {
TextRange text8(UTF8FromUTF16[fb.textRange.fStart], UTF8FromUTF16[fb.textRange.fEnd]);
fontBlocks8.emplace_back(text8, fb.typeface, fb.size, fb.style);
}
auto shapedText = std::make_unique<ShapedText>();
// Shape the text
FormattingFontIterator fontIter(text8.size(),
SkSpan<ResolvedFontBlock>(fontBlocks8.data(), fontBlocks8.size()),
SkSpan<TextIndex>(&formattingMarks[0], formattingMarks.size()));
SkShaper::TrivialLanguageRunIterator langIter(text8.c_str(), text8.size());
std::unique_ptr<SkShaper::BiDiRunIterator> bidiIter(
SkShaper::MakeSkUnicodeBidiRunIterator(
unicodeText->getUnicode(), text8.c_str(), text8.size(), textDirection == TextDirection::kLtr ? 0 : 1));
std::unique_ptr<SkShaper::ScriptRunIterator> scriptIter(
SkShaper::MakeSkUnicodeHbScriptRunIterator(unicodeText->getUnicode(), text8.c_str(), text8.size()));
auto shaper = SkShaper::MakeShapeDontWrapOrReorder();
if (shaper == nullptr) {
// For instance, loadICU does not work. We have to stop the process
return nullptr;
}
shaper->shape(
text8.c_str(), text8.size(),
fontIter, *bidiIter, *scriptIter, langIter,
std::numeric_limits<SkScalar>::max(), shapedText.get());
if (shapedText->fLogicalRuns.empty()) {
// Create a fake run for an empty text (to avoid all the checks)
SkShaper::RunHandler::RunInfo emptyInfo {
fontIter.createFont(fResolvedFonts.front()),
0,
SkVector::Make(0.0f, 0.0f),
0,
SkShaper::RunHandler::Range(0, 0)
};
shapedText->fLogicalRuns.emplace_back(emptyInfo, 0, 0.0f);
shapedText->fLogicalRuns.front().commit();
}
// Fill out all code unit properties
for (auto& logicalRun : shapedText->fLogicalRuns) {
// Convert utf8 range into utf16 range
logicalRun.convertUtf16Range([&](unsigned long index8) {
return UTF16FromUTF8[index8];
});
// Convert all utf8 indexes into utf16 indexes (and also shift them to be on the entire text scale, too)
logicalRun.convertClusterIndexes([&](TextIndex clusterIndex8) {
return UTF16FromUTF8[clusterIndex8];
});
// Detect and mark line break runs
if (logicalRun.getTextRange().width() == 1 &&
logicalRun.size() == 1 &&
unicodeText->isHardLineBreak(logicalRun.getTextRange().fStart)) {
logicalRun.setRunType(LogicalRunType::kLineBreak);
}
}
return std::move(shapedText);
}
// TODO: Implement the vertical restriction (height) and add ellipsis
std::unique_ptr<WrappedText> ShapedText::wrap(UnicodeText* unicodeText, float width, float height) {
auto wrappedText = std::unique_ptr<WrappedText>(new WrappedText());
// line + spaces + clusters
Stretch line;
Stretch spaces;
Stretch clusters;
Stretch cluster;
for (size_t runIndex = 0; runIndex < this->fLogicalRuns.size(); ++runIndex ) {
auto& run = this->fLogicalRuns[runIndex];
if (run.getRunType() == LogicalRunType::kLineBreak) {
// This is the end of the word, the end of the line
if (!clusters.isEmpty()) {
line.moveTo(spaces);
line.moveTo(clusters);
spaces = clusters;
}
this->addLine(wrappedText.get(), unicodeText->getUnicode(), line, spaces, true);
line = spaces;
clusters = spaces;
continue;
}
TextMetrics runMetrics(run.fFont);
// Let's wrap the text
GlyphRange clusterGlyphs;
DirTextRange clusterText(EMPTY_RANGE, run.leftToRight());
for (size_t glyphIndex = 0; glyphIndex < run.fPositions.size(); ++glyphIndex) {
auto textIndex = run.fClusters[glyphIndex];
if (clusterText == EMPTY_RANGE) {
// The beginning of a new line (or the first one)
clusterText = DirTextRange(textIndex, textIndex, run.leftToRight());
clusterGlyphs = GlyphRange(glyphIndex, glyphIndex);
Stretch empty(GlyphPos(runIndex, glyphIndex), textIndex, runMetrics);
line = empty;
spaces = empty;
clusters = empty;
continue;
}
if (textIndex == clusterText.fStart) {
// Skip until the next cluster
continue;
}
// Finish the cluster (notice that it belongs to a single run)
clusterText.fStart = clusterText.fEnd;
clusterText.fEnd = textIndex;
clusterGlyphs.fStart = clusterGlyphs.fEnd;
clusterGlyphs.fEnd = glyphIndex;
cluster = Stretch(runIndex, clusterGlyphs, clusterText.normalized(), run.calculateWidth(clusterGlyphs), runMetrics);
auto isSoftLineBreak = unicodeText->isSoftLineBreak(cluster.textStart());
auto isWhitespaces = unicodeText->isWhitespaces(cluster.textRange());
auto isEndOfText = run.leftToRight() ? textIndex == run.fUtf16Range.fEnd : textIndex == run.fUtf16Range.fStart;
// line + spaces + clusters + cluster
if (isWhitespaces) {
// This is the end of the word
if (!clusters.isEmpty()) {
line.moveTo(spaces);
line.moveTo(clusters);
spaces = clusters;
}
spaces.moveTo(cluster);
clusters = cluster;
// Whitespaces do not extend the line width so no wrapping
continue;
} else if (!SkScalarIsFinite(width)) {
// No wrapping - the endless line
clusters.moveTo(cluster);
continue;
}
// Now let's find out if we can add the cluster to the line
auto currentWidth = line.width() + spaces.width() + clusters.width() + cluster.width();
if (currentWidth > width) {
// Finally, the wrapping case
if (line.isEmpty()) {
if (spaces.isEmpty() && clusters.isEmpty()) {
// There is only this cluster and it's too long; we are drawing it anyway
line.moveTo(cluster);
} else {
// We break the only one word on the line by this cluster
line.moveTo(clusters);
}
} else {
// We move clusters + cluster on the next line
// TODO: Parametrise possible ways of breaking too long word
// (start it from a new line or squeeze the part of it on this line)
}
this->addLine(wrappedText.get(), unicodeText->getUnicode(), line, spaces, false);
line = spaces;
}
clusters.moveTo(cluster);
clusterGlyphs.fStart = clusterGlyphs.fEnd;
clusterText.fStart = clusterText.fEnd;
}
}
// Deal with the last line
if (!clusters.isEmpty()) {
line.moveTo(spaces);
line.moveTo(clusters);
spaces = clusters;
} else if (wrappedText->fVisualLines.empty()) {
// Empty text; we still need a line to avoid checking for empty lines every time
line.moveTo(cluster);
spaces.moveTo(cluster);
}
this->addLine(wrappedText.get(), unicodeText->getUnicode(), line, spaces, false);
wrappedText->fActualSize.fWidth = width;
return std::move(wrappedText);
}
SkTArray<int32_t> ShapedText::getVisualOrder(SkUnicode* unicode, RunIndex startRun, RunIndex endRun) {
auto numRuns = endRun - startRun + 1;
SkTArray<int32_t> results;
results.push_back_n(numRuns);
if (numRuns == 0) {
return results;
}
SkTArray<SkUnicode::BidiLevel> runLevels;
runLevels.push_back_n(numRuns);
size_t runLevelsIndex = 0;
for (RunIndex runIndex = startRun; runIndex <= endRun; ++runIndex) {
runLevels[runLevelsIndex++] = fLogicalRuns[runIndex].bidiLevel();
}
SkASSERT(runLevelsIndex == numRuns);
unicode->reorderVisual(runLevels.data(), numRuns, results.data());
return results;
}
// TODO: Fill line fOffset.fY
void ShapedText::addLine(WrappedText* wrappedText, SkUnicode* unicode, Stretch& stretch, Stretch& spaces, bool hardLineBreak) {
auto spacesStart = spaces.glyphStart();
Stretch lineStretch = stretch;
lineStretch.moveTo(spaces);
auto startRun = lineStretch.glyphStart().runIndex();
auto endRun = lineStretch.glyphEnd().runIndex();
// Reorder and cut (if needed) runs so they fit the line
auto visualOrder = std::move(this->getVisualOrder(unicode, startRun, endRun));
// Walk through the line's runs in visual order
auto firstRunIndex = startRun;
auto runStart = wrappedText->fVisualRuns.size();
SkScalar runOffsetInLine = 0.0f;
for (auto visualIndex : visualOrder) {
auto& logicalRun = fLogicalRuns[firstRunIndex + visualIndex];
if (logicalRun.getRunType() == LogicalRunType::kLineBreak) {
SkASSERT(false);
}
bool isFirstRun = startRun == (firstRunIndex + visualIndex);
bool isLastRun = endRun == (firstRunIndex + visualIndex);
bool isSpaceRun = spacesStart.runIndex() == (firstRunIndex + visualIndex);
auto glyphStart = isFirstRun ? lineStretch.glyphStart().glyphIndex() : 0;
auto glyphEnd = isLastRun ? lineStretch.glyphEnd().glyphIndex() : logicalRun.size();
auto glyphSize = glyphEnd - glyphStart;
auto glyphSpaces = isSpaceRun ? spacesStart.glyphIndex() : glyphEnd;
if (glyphSpaces > glyphStart) {
auto textStart = isFirstRun ? lineStretch.textRange().fStart : logicalRun.fUtf16Range.fStart;
auto textEnd = isLastRun ? lineStretch.textRange().fEnd : logicalRun.fUtf16Range.fEnd;
wrappedText->fVisualRuns.emplace_back(TextRange(textStart, textEnd),
glyphSpaces - glyphStart,
logicalRun.fFont,
lineStretch.textMetrics().baseline(),
SkPoint::Make(runOffsetInLine, wrappedText->fActualSize.fHeight),
logicalRun.leftToRight(),
SkSpan<SkPoint>(&logicalRun.fPositions[glyphStart], glyphSize + 1),
SkSpan<SkGlyphID>(&logicalRun.fGlyphs[glyphStart], glyphSize),
SkSpan<uint32_t>((uint32_t*)&logicalRun.fClusters[glyphStart], glyphSize + 1));
}
runOffsetInLine += logicalRun.calculateWidth(glyphStart, glyphEnd);
}
auto runRange = wrappedText->fVisualRuns.size() == runStart
? SkSpan<VisualRun>(nullptr, 0)
: SkSpan<VisualRun>(&wrappedText->fVisualRuns[runStart], wrappedText->fVisualRuns.size() - runStart);
wrappedText->fVisualLines.emplace_back(lineStretch.textRange(), hardLineBreak, wrappedText->fActualSize.fHeight, runRange);
wrappedText->fActualSize.fHeight += lineStretch.textMetrics().height();
wrappedText->fActualSize.fWidth = std::max(wrappedText->fActualSize.fWidth, lineStretch.width());
stretch.clean();
spaces.clean();
}
void WrappedText::format(TextAlign textAlign, TextDirection textDirection) {
if (fAligned == textAlign) {
return;
}
SkScalar verticalOffset = 0.0f;
for (auto& line : this->fVisualLines) {
if (textAlign == TextAlign::kLeft) {
// Good by default
} else if (textAlign == TextAlign::kCenter) {
line.fOffset.fX = (this->fActualSize.width() - line.fActualWidth) / 2.0f;
} else {
// TODO: Implement all formatting features
}
line.fOffset.fY = verticalOffset;
verticalOffset += line.fTextMetrics.height();
}
}
void WrappedText::visit(Visitor* visitor) const {
size_t lineIndex = 0;
SkScalar verticalOffset = 0.0f;
for (auto& line : fVisualLines) {
visitor->onBeginLine(lineIndex, line.text(), line.isHardBreak(), SkRect::MakeXYWH(0, verticalOffset, line.fActualWidth, line.fTextMetrics.height()));
// Select the runs that are on the line
size_t glyphCount = 0ul;
for (auto& run : line.fRuns) {
auto diff = line.fTextMetrics.above() - run.fTextMetrics.above();
SkRect boundingRect = SkRect::MakeXYWH(line.fOffset.fX + run.fPositions[0].fX, line.fOffset.fY + diff, run.width(), run.fTextMetrics.height());
visitor->onGlyphRun(run.fFont, run.dirTextRange(), boundingRect, run.trailingSpacesStart(),
run.size(), run.fGlyphs.data(), run.fPositions.data(), run.fClusters.data());
glyphCount += run.size();
}
visitor->onEndLine(lineIndex, line.text(), line.trailingSpaces(), glyphCount);
verticalOffset += line.fTextMetrics.height();
++lineIndex;
}
}
std::vector<TextIndex> WrappedText::chunksToBlocks(SkSpan<size_t> chunks) {
std::vector<TextIndex> blocks;
blocks.reserve(chunks.size() + 1);
TextIndex index = 0;
for (auto chunk : chunks) {
blocks.emplace_back(index);
index += chunk;
}
blocks.emplace_back(index);
return std::move(blocks);
}
SkSpan<TextIndex> WrappedText::limitBlocks(TextRange textRange, SkSpan<TextIndex> blocks) {
TextRange limited = EMPTY_RANGE;
for (auto i = 0ul; i < blocks.size(); ++i) {
auto block = blocks[i];
if (textRange.fEnd < block) {
continue;
} else if (textRange.fStart >= block) {
break;
} else if (limited.fStart == EMPTY_INDEX) {
limited.fStart = i;
}
limited.fEnd = i;
}
return SkSpan<TextIndex>(&blocks[textRange.fStart], textRange.width());
}
void WrappedText::visit(UnicodeText* unicodeText, Visitor* visitor, PositionType positionType, SkSpan<size_t> chunks) const {
// Decor blocks have to be sorted by text cannot intersect but can skip some parts of the text
// (in which case we use default text style from paragraph style)
// The edges of the decor blocks don't have to match glyph, grapheme or even unicode code point edges
// It's out responsibility to adjust them to some reasonable values
// [a:b) -> [c:d) where
// c is closest GG cluster edge to a from the left and d is closest GG cluster edge to b from the left
auto textBlocks = WrappedText::chunksToBlocks(chunks);
SkScalar verticalOffset = 0.0f;
LineIndex lineIndex = 0ul;
size_t glyphCount = 0ul;
for (auto& line : fVisualLines) {
visitor->onBeginLine(lineIndex, line.text(), line.isHardBreak(), SkRect::MakeXYWH(0, verticalOffset, line.fActualWidth, line.fTextMetrics.height()));
RunIndex runIndex = 0ul;
auto lineBlocks = WrappedText::limitBlocks(line.fText, SkSpan<TextIndex>(textBlocks.data(), textBlocks.size()));
for (auto& run : fVisualRuns) {
run.forEachTextBlockInGlyphRange(lineBlocks, [&](DirTextRange dirTextRange) {
GlyphRange glyphRange = this->textToGlyphs(unicodeText, positionType, runIndex, dirTextRange);
auto diff = line.fTextMetrics.above() - run.fTextMetrics.above();
SkRect boundingRect =
SkRect::MakeXYWH(line.fOffset.fX + run.fPositions[glyphRange.fStart].fX,
line.fOffset.fY + diff,
run.calculateWidth(glyphRange),
run.fTextMetrics.height());
visitor->onGlyphRun(run.fFont,
dirTextRange,
boundingRect,
run.trailingSpacesStart(),
glyphRange.width(),
&run.fGlyphs[glyphRange.fStart],
&run.fPositions[glyphRange.fStart],
&run.fClusters[glyphRange.fStart]);
});
++runIndex;
glyphCount += run.size();
}
visitor->onEndLine(lineIndex, line.text(), line.trailingSpaces(), glyphCount);
verticalOffset += line.fTextMetrics.height();
++lineIndex;
}
}
// TODO: Implement more effective search
GlyphRange WrappedText::textToGlyphs(UnicodeText* unicodeText, PositionType positionType, RunIndex runIndex, DirTextRange dirTextRange) const {
SkASSERT(runIndex < fVisualRuns.size());
auto& run = fVisualRuns[runIndex];
SkASSERT(run.fDirTextRange.contains(dirTextRange));
GlyphRange glyphRange(0, run.size());
for (GlyphIndex glyph = 0; glyph < run.size(); ++glyph) {
auto textIndex = run.fClusters[glyph];
if (positionType == PositionType::kGraphemeCluster && unicodeText->hasProperty(textIndex, CodeUnitFlags::kGraphemeStart)) {
if (dirTextRange.after(textIndex)) {
glyphRange.fStart = glyph;
} else if (dirTextRange.before(textIndex)) {
glyphRange.fEnd = glyph;
} else {
return glyphRange;
}
}
}
SkASSERT(false);
return glyphRange;
}
std::unique_ptr<SelectableText> WrappedText::prepareToEdit(UnicodeText* unicodeText) const {
auto selectableText = std::make_unique<SelectableText>();
this->visit(selectableText.get());
selectableText->fGlyphUnitProperties.push_back_n(unicodeText->getText16().size() + 1, GlyphUnitFlags::kNoGlyphUnitFlag);
for (auto index = 0; index < unicodeText->getText16().size(); ++index) {
if (unicodeText->hasProperty(index, CodeUnitFlags::kHardLineBreakBefore)) {
selectableText->fGlyphUnitProperties[index] = GlyphUnitFlags::kGraphemeClusterStart;
}
}
for (const auto& run : fVisualRuns) {
for (auto& cluster : run.fClusters) {
if (unicodeText->hasProperty(cluster, CodeUnitFlags::kGraphemeStart)) {
selectableText->fGlyphUnitProperties[cluster] = GlyphUnitFlags::kGraphemeClusterStart;
}
}
}
return selectableText;
}
void SelectableText::onBeginLine(size_t index, TextRange lineText, bool hardBreak, SkRect bounds) {
SkASSERT(fBoxLines.size() == index);
fBoxLines.emplace_back(index, lineText, hardBreak, bounds);
}
void SelectableText::onEndLine(size_t index, TextRange lineText, GlyphRange trailingSpaces, size_t glyphCount) {
auto& line = fBoxLines.back();
line.fTextEnd = trailingSpaces.fStart;
line.fTrailingSpacesEnd = trailingSpaces.fEnd;
SkASSERT(line.fTextByGlyph.size() == glyphCount);
line.fBoxGlyphs.emplace_back(SkRect::MakeXYWH(line.fBounds.fRight, line.fBounds.fTop, 0.0f, line.fBounds.height()));
if (line.fTextByGlyph.empty()) {
// Let's create an empty fake box to avoid all the checks
line.fTextByGlyph.emplace_back(lineText.fEnd);
}
line.fTextByGlyph.emplace_back(lineText.fEnd);
}
void SelectableText::onGlyphRun(const SkFont& font,
DirTextRange dirTextRange,
SkRect bounds,
TextIndex trailingSpaces,
size_t glyphCount,
const uint16_t glyphs[],
const SkPoint positions[],
const TextIndex clusters[]) {
auto& line = fBoxLines.back();
auto start = line.fTextByGlyph.size();
line.fBoxGlyphs.push_back_n(glyphCount);
line.fTextByGlyph.push_back_n(glyphCount);
for (auto i = 0; i < glyphCount; ++i) {
auto pos = positions[i];
auto pos1 = positions[i + 1];
line.fBoxGlyphs[start + i] = SkRect::MakeXYWH(pos.fX, bounds.fTop, pos1.fX - pos.fX, bounds.height());
line.fTextByGlyph[start + i] = clusters[i];
}
}
// TODO: Do something (logN) that is not a linear search
Position SelectableText::findPosition(PositionType positionType, const BoxLine& line, SkScalar x) const {
Position position(positionType);
position.fGlyphRange = GlyphRange(0, line.fBoxGlyphs.size() - 1);
position.fTextRange = line.fTextRange;
position.fBoundaries.fTop = line.fBounds.fTop;
position.fBoundaries.fBottom = line.fBounds.fBottom;
// We look for the narrowest glyph range adjusted to positionType that contains the point.
// So far we made sure that one unit of any positionType does not cross the run edges
// Therefore it's going to be represented by a single text range only
for (; position.fGlyphRange.fStart < position.fGlyphRange.fEnd; ++position.fGlyphRange.fStart) {
auto glyphBox = line.fBoxGlyphs[position.fGlyphRange.fStart];
if (glyphBox.fLeft > x) {
break;
}
if (position.fPositionType == PositionType::kGraphemeCluster) {
auto textIndex = line.fTextByGlyph[position.fGlyphRange.fStart];
if (this->hasProperty(textIndex, GlyphUnitFlags::kGraphemeClusterStart)) {
position.fTextRange.fStart = textIndex;
}
} else {
// TODO: Implement
SkASSERT(false);
}
}
for (; position.fGlyphRange.fEnd > position.fGlyphRange.fStart ; --position.fGlyphRange.fEnd) {
auto glyphBox = line.fBoxGlyphs[position.fGlyphRange.fStart];
if (glyphBox.fRight <= x) {
break;
}
if (position.fPositionType == PositionType::kGraphemeCluster) {
auto textIndex = line.fTextByGlyph[position.fGlyphRange.fEnd];
if (this->hasProperty(textIndex, GlyphUnitFlags::kGraphemeClusterStart)) {
position.fTextRange.fEnd = textIndex;
break;
}
} else {
// TODO: Implement
SkASSERT(false);
}
}
position.fLineIndex = line.fIndex;
position.fBoundaries.fLeft = line.fBoxGlyphs[position.fGlyphRange.fStart].fLeft;
position.fBoundaries.fRight = line.fBoxGlyphs[position.fGlyphRange.fEnd].fRight;
return position;
}
Position SelectableText::adjustedPosition(PositionType positionType, SkPoint xy) const {
xy.fX = std::min(xy.fX, this->fActualSize.fWidth);
xy.fY = std::min(xy.fY, this->fActualSize.fHeight);
Position position(positionType);
for (auto& line : fBoxLines) {
if (line.fBounds.fTop > xy.fY) {
// We are past the point vertically
break;
} else if (line.fBounds.fBottom <= xy.fY) {
// We haven't reached the point vertically yet
continue;
}
return this->findPosition(positionType, line, xy.fX);
}
return this->lastPosition(positionType);
}
Position SelectableText::previousPosition(Position current) const {
const BoxLine* currentLine = &fBoxLines[current.fLineIndex];
if (this->isFirstOnTheLine(current)) {
// Go to the previous line
if (current.fLineIndex == 0) {
// We reached the end; there is nowhere to move
current.fGlyphRange = GlyphRange(0, 0);
return current;
} else {
current.fLineIndex -= 1;
currentLine = &fBoxLines[current.fLineIndex];
current.fGlyphRange.fStart = currentLine->fBoxGlyphs.size();
}
}
auto position = this->findPosition(current.fPositionType, *currentLine, currentLine->fBoxGlyphs[current.fGlyphRange.fStart].centerX());
if (current.fPositionType == PositionType::kGraphemeCluster) {
// Either way we found us a grapheme cluster (just make sure of it)
SkASSERT(this->hasProperty(current.fTextRange.fStart, GlyphUnitFlags::kGraphemeClusterStart));
}
return position;
}
Position SelectableText::nextPosition(Position current) const {
const BoxLine* currentLine = &fBoxLines[current.fLineIndex];
if (this->isLastOnTheLine(current)) {
// Go to the next line
if (current.fLineIndex == this->fBoxLines.size() - 1) {
// We reached the end; there is nowhere to move
current.fGlyphRange = GlyphRange(currentLine->fBoxGlyphs.size(), currentLine->fBoxGlyphs.size());
return current;
} else {
current.fLineIndex += 1;
currentLine = &fBoxLines[current.fLineIndex];
current.fGlyphRange.fEnd = 0;
}
}
auto position = this->findPosition(current.fPositionType, *currentLine, currentLine->fBoxGlyphs[current.fGlyphRange.fStart].centerX());
if (current.fPositionType == PositionType::kGraphemeCluster) {
// Either way we found us a grapheme cluster (just make sure of it)
SkASSERT(this->hasProperty(current.fTextRange.fEnd, GlyphUnitFlags::kGraphemeClusterStart));
}
return position;
}
Position SelectableText::upPosition(Position current) const {
if (current.fLineIndex == 0) {
// We are on the first line; just move to the first position
return this->firstPosition(current.fPositionType);
}
// Go to the previous line
const BoxLine* currentLine = &fBoxLines[current.fLineIndex];
auto position = this->findPosition(current.fPositionType, fBoxLines[current.fLineIndex - 1], currentLine->fBoxGlyphs[current.fGlyphRange.fStart].centerX());
if (current.fPositionType == PositionType::kGraphemeCluster) {
// Either way we found us a grapheme cluster (just make sure of it)
SkASSERT(this->hasProperty(current.fTextRange.fEnd, GlyphUnitFlags::kGraphemeClusterStart));
}
return position;
}
Position SelectableText::downPosition(Position current) const {
if (current.fLineIndex == this->countLines() - 1) {
// We are on the last line; just move to the last position
return this->lastPosition(current.fPositionType);
}
// Go to the next line
const BoxLine* currentLine = &fBoxLines[current.fLineIndex];
auto position = this->findPosition(current.fPositionType, fBoxLines[current.fLineIndex + 1], currentLine->fBoxGlyphs[current.fGlyphRange.fStart].centerX());
if (current.fPositionType == PositionType::kGraphemeCluster) {
// Either way we found us a grapheme cluster (just make sure of it)
SkASSERT(this->hasProperty(current.fTextRange.fEnd, GlyphUnitFlags::kGraphemeClusterStart));
}
return position;
}
Position SelectableText::firstPosition(PositionType positionType) const {
auto firstLine = fBoxLines.front();
auto firstGlyph = firstLine.fBoxGlyphs.front();
Position beginningOfText(positionType);
// Set the glyph range after the last glyph
beginningOfText.fGlyphRange = GlyphRange { 0, 0};
beginningOfText.fLineIndex = 0;
beginningOfText.fBoundaries = SkRect::MakeXYWH(firstGlyph.fLeft, firstGlyph.fTop, 0, firstGlyph.height());
beginningOfText.fTextRange = this->glyphsToText(beginningOfText);
beginningOfText.fLineIndex = 0;
return beginningOfText;
}
Position SelectableText::lastPosition(PositionType positionType) const {
auto lastLine = fBoxLines.back();
auto lastGlyph = lastLine.fBoxGlyphs.back();
Position endOfText(positionType);
endOfText.fLineIndex = lastLine.fIndex;
endOfText.fGlyphRange = GlyphRange(lastLine.fBoxGlyphs.size() - 1, lastLine.fBoxGlyphs.size() - 1);
endOfText.fBoundaries = SkRect::MakeXYWH(lastGlyph.fRight, lastGlyph.fTop, 0, lastGlyph.height());
endOfText.fTextRange = this->glyphsToText(endOfText);
endOfText.fLineIndex = lastLine.fIndex;
return endOfText;
}
Position SelectableText::firstInLinePosition(PositionType positionType, LineIndex lineIndex) const {
SkASSERT(lineIndex >= 0 && lineIndex < fBoxLines.size());
auto& line = fBoxLines[lineIndex];
return this->findPosition(positionType, line, line.fBounds.left());
}
Position SelectableText::lastInLinePosition(PositionType positionType, LineIndex lineIndex) const {
auto& line = fBoxLines[lineIndex];
return this->findPosition(positionType, line, line.fBounds.right());
}
TextRange SelectableText::glyphsToText(Position position) const {
SkASSERT(position.fPositionType != PositionType::kRandomText);
auto line = this->getLine(position.fLineIndex);
TextRange textRange = EMPTY_RANGE;
for (auto glyph = position.fGlyphRange.fStart; glyph <= position.fGlyphRange.fEnd; ++glyph) {
if (textRange.fStart == EMPTY_INDEX) {
textRange.fStart = line.fTextByGlyph[glyph];
}
textRange.fEnd = line.fTextByGlyph[glyph];
}
return textRange;
}
} // namespace text
} // namespace skia