svgrootinlinebox.cpp

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            if (chunk.isVerticalText)
                curChar.y += (chunkIt - chunk.start) * spacingToApply;
            else
                curChar.x += (chunkIt - chunk.start) * spacingToApply;
        }
    }
}

void SVGRootInlineBox::computePerCharacterLayoutInformation()
{
    // Clean up any previous layout information
    m_svgChars.clear();
    m_svgTextChunks.clear();

    // Build layout information for all contained render objects
    SVGCharacterLayoutInfo info(m_svgChars);
    buildLayoutInformation(this, info);

    // Now all layout information are available for every character
    // contained in any of our child inline/flow boxes. Build list
    // of text chunks now, to be able to apply text-anchor shifts.
    buildTextChunks(m_svgChars, m_svgTextChunks, this);

    // Layout all text chunks
    // text-anchor needs to be applied to individual chunks.
    layoutTextChunks();

    // Finally the top left position of our box is known.
    // Propogate this knownledge to our RenderSVGText parent.
    FloatPoint topLeft = topLeftPositionOfCharacterRange(m_svgChars);
    block()->setLocation((int) floorf(topLeft.x()), (int) floorf(topLeft.y()));

    // Layout all InlineText/Flow boxes
    // BEWARE: This requires the root top/left position to be set correctly before!
    layoutInlineBoxes();
}

void SVGRootInlineBox::buildLayoutInformation(InlineFlowBox* start, SVGCharacterLayoutInfo& info)
{
    if (start->isRootInlineBox()) {
        ASSERT(start->renderer()->node()->hasTagName(SVGNames::textTag));

        SVGTextPositioningElement* positioningElement = static_cast<SVGTextPositioningElement*>(start->renderer()->node());
        ASSERT(positioningElement);
        ASSERT(positioningElement->parentNode());

        info.addLayoutInformation(positioningElement);
    }

    LastGlyphInfo lastGlyph;
    
    for (InlineBox* curr = start->firstChild(); curr; curr = curr->nextOnLine()) {
        if (curr->renderer()->isText())
            buildLayoutInformationForTextBox(info, static_cast<InlineTextBox*>(curr), lastGlyph);
        else {
            ASSERT(curr->isInlineFlowBox());
            InlineFlowBox* flowBox = static_cast<InlineFlowBox*>(curr);

            if (!flowBox->renderer()->node())
                continue; // Skip generated content.

            bool isAnchor = flowBox->renderer()->node()->hasTagName(SVGNames::aTag);
            bool isTextPath = flowBox->renderer()->node()->hasTagName(SVGNames::textPathTag);

            if (!isTextPath && !isAnchor) {
                SVGTextPositioningElement* positioningElement = static_cast<SVGTextPositioningElement*>(flowBox->renderer()->node());
                ASSERT(positioningElement);
                ASSERT(positioningElement->parentNode());

                info.addLayoutInformation(positioningElement);
            } else if (!isAnchor) {
                info.setInPathLayout(true);

                // Handle text-anchor/textLength on path, which is special.
                SVGTextContentElement* textContent = 0;
                Node* node = flowBox->renderer()->node();
                if (node && node->isSVGElement())
                    textContent = static_cast<SVGTextContentElement*>(node);
                ASSERT(textContent);

                ELengthAdjust lengthAdjust = (ELengthAdjust) textContent->lengthAdjust();
                ETextAnchor anchor = flowBox->renderer()->style()->svgStyle()->textAnchor();
                float textAnchorStartOffset = 0.0f;

                // Initialize sub-layout. We need to create text chunks from the textPath
                // children using our standard layout code, to be able to measure the
                // text length using our normal methods and not textPath specific hacks.
                Vector<SVGChar> tempChars;
                Vector<SVGTextChunk> tempChunks;

                SVGCharacterLayoutInfo tempInfo(tempChars);
                buildLayoutInformation(flowBox, tempInfo);

                buildTextChunks(tempChars, tempChunks, flowBox);

                Vector<SVGTextChunk>::iterator it = tempChunks.begin();
                Vector<SVGTextChunk>::iterator end = tempChunks.end();

                TransformationMatrix ctm;
                float computedLength = 0.0f;
 
                for (; it != end; ++it) {
                    SVGTextChunk& chunk = *it;

                    // Apply text-length calculation
                    info.pathExtraAdvance += calculateTextLengthCorrectionForTextChunk(chunk, lengthAdjust, computedLength);

                    if (lengthAdjust == SVGTextContentElement::LENGTHADJUST_SPACINGANDGLYPHS) {
                        info.pathTextLength += computedLength;
                        info.pathChunkLength += chunk.textLength;
                    }

                    // Calculate text-anchor start offset
                    if (anchor == TA_START)
                        continue;

                    textAnchorStartOffset += calculateTextAnchorShiftForTextChunk(chunk, anchor);
                }

                info.addLayoutInformation(flowBox, textAnchorStartOffset);
            }

            float shiftxSaved = info.shiftx;
            float shiftySaved = info.shifty;

            buildLayoutInformation(flowBox, info);
            info.processedChunk(shiftxSaved, shiftySaved);

            if (isTextPath)
                info.setInPathLayout(false);
        }
    }
}

void SVGRootInlineBox::layoutInlineBoxes()
{
    int lowX = INT_MAX;
    int lowY = INT_MAX;
    int highX = INT_MIN;
    int highY = INT_MIN;

    // Layout all child boxes
    Vector<SVGChar>::iterator it = m_svgChars.begin(); 
    layoutInlineBoxes(this, it, lowX, highX, lowY, highY);
    ASSERT(it == m_svgChars.end());
}

void SVGRootInlineBox::layoutInlineBoxes(InlineFlowBox* start, Vector<SVGChar>::iterator& it, int& lowX, int& highX, int& lowY, int& highY)
{
    for (InlineBox* curr = start->firstChild(); curr; curr = curr->nextOnLine()) {
        RenderStyle* style = curr->renderer()->style();    
        if (curr->renderer()->isText()) {
            SVGInlineTextBox* textBox = static_cast<SVGInlineTextBox*>(curr);
            unsigned length = textBox->len();

            SVGChar curChar = *it; 
            ASSERT(it != m_svgChars.end());  

            FloatRect stringRect;
            for (unsigned i = 0; i < length; ++i) {
                ASSERT(it != m_svgChars.end());

                if (it->isHidden()) {
                    ++it;
                    continue;
                }

                stringRect.unite(textBox->calculateGlyphBoundaries(style, textBox->start() + i, *it));
                ++it;
            }

            IntRect enclosedStringRect = enclosingIntRect(stringRect);

            int minX = enclosedStringRect.x();
            int maxX = minX + enclosedStringRect.width();

            int minY = enclosedStringRect.y();
            int maxY = minY + enclosedStringRect.height();

            curr->setX(minX - block()->x());
            curr->setWidth(enclosedStringRect.width());

            curr->setY(minY - block()->y());
            textBox->setHeight(enclosedStringRect.height());

            if (minX < lowX)
                lowX = minX;

            if (maxX > highX)
                highX = maxX;

            if (minY < lowY)
                lowY = minY;

            if (maxY > highY)
                highY = maxY;
        } else {
            ASSERT(curr->isInlineFlowBox());

            int minX = INT_MAX;
            int minY = INT_MAX;
            int maxX = INT_MIN;
            int maxY = INT_MIN;

            InlineFlowBox* flowBox = static_cast<InlineFlowBox*>(curr);
            
            if (!flowBox->renderer()->node())
                continue; // Skip generated content.
    
            layoutInlineBoxes(flowBox, it, minX, maxX, minY, maxY);

            curr->setX(minX - block()->x());
            curr->setWidth(maxX - minX);

            curr->setY(minY - block()->y());
            static_cast<SVGInlineFlowBox*>(curr)->setHeight(maxY - minY);

            if (minX < lowX)
                lowX = minX;

            if (maxX > highX)
                highX = maxX;

            if (minY < lowY)
                lowY = minY;

            if (maxY > highY)
                highY = maxY;
        }
    }

    if (start->isSVGRootInlineBox()) {
        int top = lowY - block()->y();
        int bottom = highY - block()->y();

        start->setX(lowX - block()->x());
        start->setY(top);

        start->setWidth(highX - lowX);
        static_cast<SVGRootInlineBox*>(start)->setHeight(highY - lowY);

        start->setVerticalOverflowPositions(top, bottom);
        start->setVerticalSelectionPositions(top, bottom);
    }
}

void SVGRootInlineBox::buildLayoutInformationForTextBox(SVGCharacterLayoutInfo& info, InlineTextBox* textBox, LastGlyphInfo& lastGlyph)
{
    RenderText* text = textBox->textRenderer();
    ASSERT(text);

    RenderStyle* style = text->style(textBox->isFirstLineStyle());
    ASSERT(style);

    const Font& font = style->font();
    SVGInlineTextBox* svgTextBox = static_cast<SVGInlineTextBox*>(textBox);

    unsigned length = textBox->len();

    const SVGRenderStyle* svgStyle = style->svgStyle();
    bool isVerticalText = isVerticalWritingMode(svgStyle);

    int charsConsumed = 0;
    for (unsigned i = 0; i < length; i += charsConsumed) {
        SVGChar svgChar;

        if (info.inPathLayout())
            svgChar.pathData = SVGCharOnPath::create();

        float glyphWidth = 0.0f;
        float glyphHeight = 0.0f;

        int extraCharsAvailable = length - i - 1;

        String unicodeStr;
        String glyphName;
        if (textBox->direction() == RTL) {
            glyphWidth = svgTextBox->calculateGlyphWidth(style, textBox->end() - i, extraCharsAvailable, charsConsumed, glyphName);
            glyphHeight = svgTextBox->calculateGlyphHeight(style, textBox->end() - i, extraCharsAvailable);
            unicodeStr = String(textBox->textRenderer()->text()->characters() + textBox->end() - i, charsConsumed);
        } else {
            glyphWidth = svgTextBox->calculateGlyphWidth(style, textBox->start() + i, extraCharsAvailable, charsConsumed, glyphName);
            glyphHeight = svgTextBox->calculateGlyphHeight(style, textBox->start() + i, extraCharsAvailable);
            unicodeStr = String(textBox->textRenderer()->text()->characters() + textBox->start() + i, charsConsumed);
        }

        bool assignedX = false;
        bool assignedY = false;

        if (info.xValueAvailable() && (!info.inPathLayout() || (info.inPathLayout() && !isVerticalText))) {
            if (!isVerticalText)
                svgChar.newTextChunk = true;

            assignedX = true;
            svgChar.drawnSeperated = true;
            info.curx = info.xValueNext();
        }

        if (info.yValueAvailable() && (!info.inPathLayout() || (info.inPathLayout() && isVerticalText))) {
            if (isVerticalText)
                svgChar.newTextChunk = true;

            assignedY = true;
            svgChar.drawnSeperated = true;
            info.cury = info.yValueNext();
        }

        float dx = 0.0f;
        float dy = 0.0f;

        // Apply x-axis shift
        if (info.dxValueAvailable()) {
            svgChar.drawnSeperated = true;

            dx = info.dxValueNext();
            info.dx += dx;

            if (!info.inPathLayout())
                info.curx += dx;
        }

        // Apply y-axis shift
        if (info.dyValueAvailable()) {
            svgChar.drawnSeperated = true;

            dy = info.dyValueNext();
            info.dy += dy;

            if (!info.inPathLayout())
                info.cury += dy;
        }

        // Take letter & word spacing and kerning into account
        float spacing = font.letterSpacing() + calculateKerning(textBox->renderer()->node()->renderer());

        const UChar* currentCharacter = text->characters() + (textBox->direction() == RTL ? textBox->end() - i : textBox->start() + i);
        const UChar* lastCharacter = 0;

        if (textBox->direction() == RTL) {
            if (i < textBox->end())
                lastCharacter = text->characters() + textBox->end() - i +  1;
        } else {
            if (i > 0)
                lastCharacter = text->characters() + textBox->start() + i - 1;
        }

        if (info.nextDrawnSeperated || spacing != 0.0f) {
            info.nextDrawnSeperated = false;
            svgChar.drawnSeperated = true;
        }

        if (currentCharacter && Font::treatAsSpace(*currentCharacter) && lastCharacter && !Font::treatAsSpace(*lastCharacter)) {
            spacing += font.wordSpacing();

            if (spacing != 0.0f && !info.inPathLayout())
                info.nextDrawnSeperated = true;
        }

        float orientationAngle = glyphOrientationToAngle(svgStyle, isVerticalText, *currentCharacter);

        float xOrientationShift = 0.0f;
        float yOrientationShift = 0.0f;
        float glyphAdvance = calculateGlyphAdvanceAndShiftRespectingOrientation(isVerticalText, orientationAngle, glyphWidth, glyphHeight,
                                                                                font, svgChar, xOrientationShift, yOrientationShift);

        // Handle textPath layout mode
        if (info.inPathLayout()) {
            float extraAdvance = isVerticalText ? dy : dx;
            float newOffset = FLT_MIN;

            if (assignedX && !isVerticalText)
                newOffset = info.curx;
            else if (assignedY && isVerticalText)
                newOffset = info.cury;

            float correctedGlyphAdvance = glyphAdvance;

            // Handle lengthAdjust="spacingAndGlyphs" by specifying per-character scale operations
            if (info.pathTextLength > 0.0f && info.pathChunkLength > 0.0f) { 
                if (isVerticalText) {
                    svgChar.pathData->yScale = info.pathChunkLength / info.pathTextLength;
                    spacing *= svgChar.pathData->yScale;
                    correctedGlyphAdvance *= svgChar.pathData->yScale;
                } else {
                    svgChar.pathData->xScale = info.pathChunkLength / info.pathTextLength;
                    spacing *= svgChar.pathData->xScale;
                    correctedGlyphAdvance *= svgChar.pathData->xScale;
                }
            }

            // Handle letter & word spacing on text path
            float pathExtraAdvance = info.pathExtraAdvance;
            info.pathExtraAdvance += spacing;

            svgChar.pathData->hidden = !info.nextPathLayoutPointAndAngle(correctedGlyphAdvance, extraAdvance, newOffset);
            svgChar.drawnSeperated = true;

            info.pathExtraAdvance = pathExtraAdvance;
        }

        // Apply rotation
        if (info.angleValueAvailable())
            info.angle = info.angleValueNext();

        // Apply baseline-shift
        if (info.baselineShiftValueAvailable()) {
            svgChar.drawnSeperated = true;
            float shift = info.baselineShiftValueNext();

            if (isVerticalText)
                info.shiftx += shift;
            else
                info.shifty -= shift;
        }

        // Take dominant-baseline / alignment-baseline into account
        yOrientationShift += alignmentBaselineToShift(isVerticalText, text, font);

        svgChar.x = info.curx;
        svgChar.y = info.cury;
        svgChar.angle = info.angle;

        // For text paths any shift (dx/dy/baseline-shift) has to be applied after the rotation
        if (!info.inPathLayout()) {
            svgChar.x += info.shiftx + xOrientationShift;
            svgChar.y += info.shifty + yOrientationShift;

            if (orientationAngle != 0.0f)