void SVGTextLayoutAttributesBuilder::buildLayoutScopes(RenderObject* start, unsigned& atCharacter, UChar& lastCharacter)
{
for (RenderObject* child = start->firstChild(); child; child = child->nextSibling()) {
if (child->isSVGInlineText()) {
RenderSVGInlineText* text = toRenderSVGInlineText(child);
if (!shouldPreserveAllWhiteSpace(text->style())) {
const UChar* characters = text->characters();
unsigned textLength = text->textLength();
for (unsigned textPosition = 0; textPosition < textLength; ++textPosition) {
const UChar& currentCharacter = characters[textPosition];
if (characterIsSpace(currentCharacter) && characterIsSpaceOrNull(lastCharacter))
continue;
lastCharacter = currentCharacter;
++atCharacter;
}
} else
atCharacter += text->textLength();
continue;
}
if (!child->isSVGInline())
continue;
unsigned textContentStart = atCharacter;
buildLayoutScopes(child, atCharacter, lastCharacter);
LayoutScope scope;
buildLayoutScope(scope, child, textContentStart, atCharacter - textContentStart);
m_scopes.append(scope);
}
}
static inline void writeSVGInlineTextBox(TextStream& ts, SVGInlineTextBox* textBox, int indent)
{
Vector<SVGTextFragment>& fragments = textBox->textFragments();
if (fragments.isEmpty())
return;
RenderSVGInlineText* textRenderer = toRenderSVGInlineText(textBox->textRenderer());
ASSERT(textRenderer);
const SVGRenderStyle* svgStyle = textRenderer->style()->svgStyle();
String text = textBox->textRenderer()->text();
unsigned fragmentsSize = fragments.size();
for (unsigned i = 0; i < fragmentsSize; ++i) {
SVGTextFragment& fragment = fragments.at(i);
writeIndent(ts, indent + 1);
unsigned startOffset = fragment.characterOffset;
unsigned endOffset = fragment.characterOffset + fragment.length;
// FIXME: Remove this hack, once the new text layout engine is completly landed. We want to preserve the old layout test results for now.
ts << "chunk 1 ";
ETextAnchor anchor = svgStyle->textAnchor();
bool isVerticalText = svgStyle->isVerticalWritingMode();
if (anchor == TA_MIDDLE) {
ts << "(middle anchor";
if (isVerticalText)
ts << ", vertical";
ts << ") ";
} else if (anchor == TA_END) {
ts << "(end anchor";
if (isVerticalText)
ts << ", vertical";
ts << ") ";
} else if (isVerticalText)
ts << "(vertical) ";
startOffset -= textBox->start();
endOffset -= textBox->start();
// </hack>
ts << "text run " << i + 1 << " at (" << fragment.x << "," << fragment.y << ")";
ts << " startOffset " << startOffset << " endOffset " << endOffset;
if (isVerticalText)
ts << " height " << fragment.height;
else
ts << " width " << fragment.width;
if (!textBox->isLeftToRightDirection() || textBox->dirOverride()) {
ts << (textBox->isLeftToRightDirection() ? " LTR" : " RTL");
if (textBox->dirOverride())
ts << " override";
}
ts << ": " << quoteAndEscapeNonPrintables(text.substring(fragment.characterOffset, fragment.length)) << "\n";
}
}
void SVGTextLayoutAttributesBuilder::propagateLayoutAttributes(RenderObject* start, unsigned& atCharacter, UChar& lastCharacter) const
{
for (RenderObject* child = start->firstChild(); child; child = child->nextSibling()) {
if (child->isSVGInlineText()) {
RenderSVGInlineText* text = toRenderSVGInlineText(child);
const UChar* characters = text->characters();
unsigned textLength = text->textLength();
bool preserveWhiteSpace = shouldPreserveAllWhiteSpace(text->style());
SVGTextLayoutAttributes attributes;
attributes.reserveCapacity(textLength);
unsigned valueListPosition = atCharacter;
unsigned metricsLength = 1;
for (unsigned textPosition = 0; textPosition < textLength; textPosition += metricsLength) {
const UChar& currentCharacter = characters[textPosition];
SVGTextMetrics metrics = SVGTextMetrics::measureCharacterRange(text, textPosition, 1);
metricsLength = metrics.length();
if (!preserveWhiteSpace && characterIsSpace(currentCharacter) && characterIsSpaceOrNull(lastCharacter)) {
assignEmptyLayoutAttributesForCharacter(attributes);
attributes.textMetricsValues().append(SVGTextMetrics::emptyMetrics());
continue;
}
assignLayoutAttributesForCharacter(attributes, metrics, valueListPosition);
if (metricsLength > 1) {
for (unsigned i = 0; i < metricsLength - 1; ++i)
assignEmptyLayoutAttributesForCharacter(attributes);
}
lastCharacter = currentCharacter;
valueListPosition += metricsLength;
}
#if DUMP_TEXT_LAYOUT_ATTRIBUTES > 0
fprintf(stderr, "\nDumping layout attributes for RenderSVGInlineText, renderer=%p, node=%p (atCharacter: %i)\n", text, text->node(), atCharacter);
attributes.dump();
#endif
text->storeLayoutAttributes(attributes);
atCharacter = valueListPosition;
continue;
}
if (!child->isSVGInline())
continue;
propagateLayoutAttributes(child, atCharacter, lastCharacter);
}
}
static inline void processRenderSVGInlineText(const RenderSVGInlineText& text, unsigned& atCharacter, bool& lastCharacterWasSpace)
{
if (text.style().whiteSpace() == PRE) {
atCharacter += text.textLength();
return;
}
for (unsigned textPosition = 0, textLength = text.textLength(); textPosition < textLength; ++textPosition) {
const UChar currentCharacter = text[textPosition];
if (currentCharacter == ' ' && lastCharacterWasSpace)
continue;
lastCharacterWasSpace = currentCharacter == ' ';
++atCharacter;
}
}
void SVGTextMetricsCalculator::setupBidiRuns()
{
RenderStyle* style = m_text->style();
m_textDirection = style->direction();
if (isOverride(style->unicodeBidi()))
return;
BidiStatus status(LTR, false);
status.last = status.lastStrong = WTF::Unicode::OtherNeutral;
m_bidiResolver.setStatus(status);
m_bidiResolver.setPositionIgnoringNestedIsolates(TextRunIterator(&m_run, 0));
const bool hardLineBreak = false;
const bool reorderRuns = false;
m_bidiResolver.createBidiRunsForLine(TextRunIterator(&m_run, m_run.length()), NoVisualOverride, hardLineBreak, reorderRuns);
BidiRunList<BidiCharacterRun>& bidiRuns = m_bidiResolver.runs();
m_bidiRun = bidiRuns.firstRun();
}
int SVGInlineTextBox::offsetForPositionInFragment(const SVGTextFragment& fragment, float position, bool includePartialGlyphs) const
{
RenderSVGInlineText* textRenderer = toRenderSVGInlineText(this->textRenderer());
ASSERT(textRenderer);
float scalingFactor = textRenderer->scalingFactor();
ASSERT(scalingFactor);
RenderStyle* style = textRenderer->style();
ASSERT(style);
TextRun textRun = constructTextRun(style, fragment);
// Eventually handle lengthAdjust="spacingAndGlyphs".
// FIXME: Handle vertical text.
AffineTransform fragmentTransform;
fragment.buildFragmentTransform(fragmentTransform);
if (!fragmentTransform.isIdentity())
textRun.setHorizontalGlyphStretch(narrowPrecisionToFloat(fragmentTransform.xScale()));
return fragment.characterOffset - start() + textRenderer->scaledFont().offsetForPosition(textRun, position * scalingFactor, includePartialGlyphs);
}
void SVGTextLayoutEngine::layoutInlineTextBox(SVGInlineTextBox* textBox)
{
ASSERT(textBox);
RenderSVGInlineText* text = toRenderSVGInlineText(textBox->textRenderer());
ASSERT(text);
ASSERT(text->parent());
ASSERT(text->parent()->node());
ASSERT(text->parent()->node()->isSVGElement());
const RenderStyle* style = text->style();
ASSERT(style);
textBox->clearTextFragments();
m_isVerticalText = style->svgStyle()->isVerticalWritingMode();
layoutTextOnLineOrPath(textBox, text, style);
if (m_inPathLayout) {
m_pathLayoutBoxes.append(textBox);
return;
}
m_lineLayoutBoxes.append(textBox);
}
void SVGTextChunkBuilder::addTextChunk(Vector<SVGInlineTextBox*>& lineLayoutBoxes, unsigned boxStart, unsigned boxCount)
{
SVGInlineTextBox* textBox = lineLayoutBoxes[boxStart];
ASSERT(textBox);
RenderSVGInlineText* textRenderer = toRenderSVGInlineText(textBox->textRenderer());
ASSERT(textRenderer);
const RenderStyle* style = textRenderer->style();
ASSERT(style);
const SVGRenderStyle* svgStyle = style->svgStyle();
ASSERT(svgStyle);
// Build chunk style flags.
unsigned chunkStyle = SVGTextChunk::DefaultStyle;
// Handle 'direction' property.
if (!style->isLeftToRightDirection())
chunkStyle |= SVGTextChunk::RightToLeftText;
// Handle 'writing-mode' property.
if (svgStyle->isVerticalWritingMode())
chunkStyle |= SVGTextChunk::VerticalText;
// Handle 'text-anchor' property.
switch (svgStyle->textAnchor()) {
case TA_START:
break;
case TA_MIDDLE:
chunkStyle |= SVGTextChunk::MiddleAnchor;
break;
case TA_END:
chunkStyle |= SVGTextChunk::EndAnchor;
break;
};
// Handle 'lengthAdjust' property.
float desiredTextLength = 0;
if (SVGTextContentElement* textContentElement = SVGTextContentElement::elementFromRenderer(textRenderer->parent())) {
desiredTextLength = textContentElement->specifiedTextLength().value(textContentElement);
switch (textContentElement->lengthAdjust()) {
case SVGTextContentElement::LENGTHADJUST_UNKNOWN:
break;
case SVGTextContentElement::LENGTHADJUST_SPACING:
chunkStyle |= SVGTextChunk::LengthAdjustSpacing;
break;
case SVGTextContentElement::LENGTHADJUST_SPACINGANDGLYPHS:
chunkStyle |= SVGTextChunk::LengthAdjustSpacingAndGlyphs;
break;
};
}
SVGTextChunk chunk(chunkStyle, desiredTextLength);
Vector<SVGInlineTextBox*>& boxes = chunk.boxes();
for (unsigned i = boxStart; i < boxStart + boxCount; ++i)
boxes.append(lineLayoutBoxes[i]);
m_textChunks.append(chunk);
}
void SVGTextLayoutAttributesBuilder::propagateLayoutAttributes(RenderObject* start, Vector<SVGTextLayoutAttributes>& allAttributes, unsigned& atCharacter, UChar& lastCharacter) const
{
for (RenderObject* child = start->firstChild(); child; child = child->nextSibling()) {
if (child->isSVGInlineText()) {
RenderSVGInlineText* text = toRenderSVGInlineText(child);
const UChar* characters = text->characters();
unsigned textLength = text->textLength();
bool preserveWhiteSpace = shouldPreserveAllWhiteSpace(text->style());
SVGTextLayoutAttributes attributes(text);
attributes.reserveCapacity(textLength);
unsigned valueListPosition = atCharacter;
unsigned metricsLength = 1;
SVGTextMetrics lastMetrics(SVGTextMetrics::SkippedSpaceMetrics);
for (unsigned textPosition = 0; textPosition < textLength; textPosition += metricsLength) {
const UChar& currentCharacter = characters[textPosition];
SVGTextMetrics startToCurrentMetrics;
SVGTextMetrics currentMetrics;
unsigned valueListAdvance = 0;
if (U16_IS_LEAD(currentCharacter) && (textPosition + 1) < textLength && U16_IS_TRAIL(characters[textPosition + 1])) {
// Handle surrogate pairs.
startToCurrentMetrics = SVGTextMetrics::measureCharacterRange(text, 0, textPosition + 2);
currentMetrics = SVGTextMetrics::measureCharacterRange(text, textPosition, 2);
metricsLength = currentMetrics.length();
valueListAdvance = 1;
} else {
// Handle BMP characters.
startToCurrentMetrics = SVGTextMetrics::measureCharacterRange(text, 0, textPosition + 1);
currentMetrics = SVGTextMetrics::measureCharacterRange(text, textPosition, 1);
metricsLength = currentMetrics.length();
valueListAdvance = metricsLength;
}
if (!metricsLength)
break;
// Frequent case for Arabic text: when measuring a single character the arabic isolated form is taken
// when rendering the glyph "in context" (with it's surrounding characters) it changes due to shaping.
// So whenever runWidthAdvance != currentMetrics.width(), we are processing a text run whose length is
// not equal to the sum of the individual lengths of the glyphs, when measuring them isolated.
float runWidthAdvance = startToCurrentMetrics.width() - lastMetrics.width();
if (runWidthAdvance != currentMetrics.width())
currentMetrics.setWidth(runWidthAdvance);
lastMetrics = startToCurrentMetrics;
if (!preserveWhiteSpace && characterIsSpace(currentCharacter) && characterIsSpaceOrNull(lastCharacter)) {
attributes.positioningLists().appendEmptyValues();
attributes.textMetricsValues().append(SVGTextMetrics(SVGTextMetrics::SkippedSpaceMetrics));
continue;
}
SVGTextLayoutAttributes::PositioningLists& positioningLists = attributes.positioningLists();
positioningLists.appendValuesFromPosition(m_positioningLists, valueListPosition);
attributes.textMetricsValues().append(currentMetrics);
// Pad x/y/dx/dy/rotate value lists with empty values, if the metrics span more than one character.
if (metricsLength > 1) {
for (unsigned i = 0; i < metricsLength - 1; ++i)
positioningLists.appendEmptyValues();
}
lastCharacter = currentCharacter;
valueListPosition += valueListAdvance;
}
#if DUMP_TEXT_LAYOUT_ATTRIBUTES > 0
fprintf(stderr, "\nDumping layout attributes for RenderSVGInlineText, renderer=%p, node=%p (atCharacter: %i)\n", text, text->node(), atCharacter);
fprintf(stderr, "BiDi properties: unicode-bidi=%i, block direction=%i\n", text->style()->unicodeBidi(), text->style()->direction());
attributes.dump();
#endif
text->storeLayoutAttributes(attributes);
allAttributes.append(attributes);
atCharacter = valueListPosition;
continue;
}
if (!child->isSVGInline())
continue;
propagateLayoutAttributes(child, allAttributes, atCharacter, lastCharacter);
}
}
