svgrootinlinebox.cpp

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        // Finalize text rendering 
        if (!flowBox->isRootInlineBox()) {
            finishRenderSVGContent(object, m_paintInfo, m_boundingBox, m_filter, m_savedInfo.context);
            m_filter = 0;
        }

        // Restore context & repaint rect
        m_paintInfo.context->restore();
        m_paintInfo.rect = m_savedInfo.rect;
    }

    bool chunkSetupFillCallback(InlineBox* box)
    {
        InlineFlowBox* flowBox = box->parent();

        // Setup fill paint server
        RenderObject* object = flowBox->renderer();
        ASSERT(object);

        ASSERT(!m_strokePaintServer);
        teardownFillPaintServer();

        m_fillPaintServer = SVGPaintServer::fillPaintServer(object->style(), object);
        if (m_fillPaintServer) {
            m_fillPaintServer->setup(m_paintInfo.context, object, ApplyToFillTargetType, true);
            m_fillPaintServerObject = object;
            return true;
        }

        return false;
    }

    bool chunkSetupStrokeCallback(InlineBox* box)
    {
        InlineFlowBox* flowBox = box->parent();

        // Setup stroke paint server
        RenderObject* object = flowBox->renderer();
        ASSERT(object);

        // If we're both stroked & filled, teardown fill paint server before stroking.
        teardownFillPaintServer();
        teardownStrokePaintServer();

        m_strokePaintServer = SVGPaintServer::strokePaintServer(object->style(), object);

        if (m_strokePaintServer) {
            m_strokePaintServer->setup(m_paintInfo.context, object, ApplyToStrokeTargetType, true);
            m_strokePaintServerObject = object;
            return true;
        }

        return false;
    }

    void chunkPortionCallback(SVGInlineTextBox* textBox, int startOffset, const TransformationMatrix& chunkCtm,
                              const Vector<SVGChar>::iterator& start, const Vector<SVGChar>::iterator& end)
    {
        RenderText* text = textBox->textRenderer();
        ASSERT(text);

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

        startOffset += textBox->start();

        int textDecorations = styleToUse->textDecorationsInEffect(); 

        int textWidth = 0;
        IntPoint decorationOrigin;
        SVGTextDecorationInfo info;

        if (!chunkCtm.isIdentity())
            m_paintInfo.context->concatCTM(chunkCtm);

        for (Vector<SVGChar>::iterator it = start; it != end; ++it) {
            if (it->isHidden())
                continue;

            // Determine how many characters - starting from the current - can be drawn at once.
            Vector<SVGChar>::iterator itSearch = it + 1;
            while (itSearch != end) {
                if (itSearch->drawnSeperated || itSearch->isHidden())
                    break;

                itSearch++;
            }

            const UChar* stringStart = text->characters() + startOffset + (it - start);
            unsigned int stringLength = itSearch - it;

            // Paint decorations, that have to be drawn before the text gets drawn
            if (textDecorations != TDNONE && m_paintInfo.phase != PaintPhaseSelection) {
                textWidth = styleToUse->font().width(svgTextRunForInlineTextBox(stringStart, stringLength, styleToUse, textBox, (*it).x));
                decorationOrigin = IntPoint((int) (*it).x, (int) (*it).y - styleToUse->font().ascent());
                info = m_rootBox->retrievePaintServersForTextDecoration(text);
            }

            if (textDecorations & UNDERLINE && textWidth != 0.0f)
                textBox->paintDecoration(UNDERLINE, m_paintInfo.context, decorationOrigin.x(), decorationOrigin.y(), textWidth, *it, info);

            if (textDecorations & OVERLINE && textWidth != 0.0f)
                textBox->paintDecoration(OVERLINE, m_paintInfo.context, decorationOrigin.x(), decorationOrigin.y(), textWidth, *it, info);

            // Paint text
            SVGPaintServer* activePaintServer = m_fillPaintServer;
            if (!activePaintServer)
                activePaintServer = m_strokePaintServer;

            ASSERT(activePaintServer);
            textBox->paintCharacters(m_paintInfo, m_tx, m_ty, *it, stringStart, stringLength, activePaintServer);

            // Paint decorations, that have to be drawn afterwards
            if (textDecorations & LINE_THROUGH && textWidth != 0.0f)
                textBox->paintDecoration(LINE_THROUGH, m_paintInfo.context, decorationOrigin.x(), decorationOrigin.y(), textWidth, *it, info);

            // Skip processed characters
            it = itSearch - 1;
        }

        if (!chunkCtm.isIdentity())
            m_paintInfo.context->concatCTM(chunkCtm.inverse());
    }

private:
    SVGRootInlineBox* m_rootBox;
    bool m_chunkStarted : 1;

    RenderObject::PaintInfo m_paintInfo;
    RenderObject::PaintInfo m_savedInfo;

    FloatRect m_boundingBox;
    SVGResourceFilter* m_filter;
    SVGResourceFilter* m_rootFilter;

    SVGPaintServer* m_fillPaintServer;
    SVGPaintServer* m_strokePaintServer;

    RenderObject* m_fillPaintServerObject;
    RenderObject* m_strokePaintServerObject;

    int m_tx;
    int m_ty;
};

void SVGRootInlineBox::paint(RenderObject::PaintInfo& paintInfo, int tx, int ty)
{
    if (paintInfo.context->paintingDisabled() || paintInfo.phase != PaintPhaseForeground)
        return;

    RenderObject::PaintInfo savedInfo(paintInfo);
    paintInfo.context->save();

    SVGResourceFilter* filter = 0;
    FloatRect boundingBox(tx + x(), ty + y(), width(), height());

    // Initialize text rendering
    paintInfo.context->concatCTM(renderer()->localTransform());
    prepareToRenderSVGContent(renderer(), paintInfo, boundingBox, filter);
    paintInfo.context->concatCTM(renderer()->localTransform().inverse());
 
    // Render text, chunk-by-chunk
    SVGRootInlineBoxPaintWalker walkerCallback(this, filter, paintInfo, tx, ty);
    SVGTextChunkWalker<SVGRootInlineBoxPaintWalker> walker(&walkerCallback,
                                                           &SVGRootInlineBoxPaintWalker::chunkPortionCallback,
                                                           &SVGRootInlineBoxPaintWalker::chunkStartCallback,
                                                           &SVGRootInlineBoxPaintWalker::chunkEndCallback,
                                                           &SVGRootInlineBoxPaintWalker::chunkSetupFillCallback,
                                                           &SVGRootInlineBoxPaintWalker::chunkSetupStrokeCallback);

    walkTextChunks(&walker);

    // Finalize text rendering 
    finishRenderSVGContent(renderer(), paintInfo, boundingBox, filter, savedInfo.context);
    paintInfo.context->restore();
}

int SVGRootInlineBox::placeBoxesHorizontally(int, int& leftPosition, int& rightPosition, bool&)
{
    // Remove any offsets caused by RTL text layout
    leftPosition = 0;
    rightPosition = 0;
    return 0;
}

int SVGRootInlineBox::verticallyAlignBoxes(int)
{
    // height is set by layoutInlineBoxes.
    return height();
}

float cummulatedWidthOfInlineBoxCharacterRange(SVGInlineBoxCharacterRange& range)
{
    ASSERT(!range.isOpen());
    ASSERT(range.isClosed());
    ASSERT(range.box->isInlineTextBox());

    InlineTextBox* textBox = static_cast<InlineTextBox*>(range.box);
    RenderText* text = textBox->textRenderer();
    RenderStyle* style = text->style();

    return style->font().floatWidth(svgTextRunForInlineTextBox(text->characters() + textBox->start() + range.startOffset, range.endOffset - range.startOffset, style, textBox, 0));
}

float cummulatedHeightOfInlineBoxCharacterRange(SVGInlineBoxCharacterRange& range)
{
    ASSERT(!range.isOpen());
    ASSERT(range.isClosed());
    ASSERT(range.box->isInlineTextBox());

    InlineTextBox* textBox = static_cast<InlineTextBox*>(range.box);
    RenderText* text = textBox->textRenderer();
    const Font& font = text->style()->font();

    return (range.endOffset - range.startOffset) * (font.ascent() + font.descent());
}

TextRun svgTextRunForInlineTextBox(const UChar* c, int len, RenderStyle* style, const InlineTextBox* textBox, float xPos)
{
    ASSERT(textBox);
    ASSERT(style);

    TextRun run(c, len, false, static_cast<int>(xPos), textBox->toAdd(), textBox->direction() == RTL, textBox->m_dirOverride || style->visuallyOrdered());

#if ENABLE(SVG_FONTS)
    run.setReferencingRenderObject(textBox->textRenderer()->parent());
#endif

    // We handle letter & word spacing ourselves
    run.disableSpacing();
    return run;
}

static float cummulatedWidthOrHeightOfTextChunk(SVGTextChunk& chunk, bool calcWidthOnly)
{
    float length = 0.0f;
    Vector<SVGChar>::iterator charIt = chunk.start;

    Vector<SVGInlineBoxCharacterRange>::iterator it = chunk.boxes.begin();
    Vector<SVGInlineBoxCharacterRange>::iterator end = chunk.boxes.end();

    for (; it != end; ++it) {
        SVGInlineBoxCharacterRange& range = *it;

        SVGInlineTextBox* box = static_cast<SVGInlineTextBox*>(range.box);
        RenderStyle* style = box->renderer()->style();

        for (int i = range.startOffset; i < range.endOffset; ++i) {
            ASSERT(charIt <= chunk.end);

            // Determine how many characters - starting from the current - can be measured at once.
            // Important for non-absolute positioned non-latin1 text (ie. Arabic) where ie. the width
            // of a string is not the sum of the boundaries of all contained glyphs.
            Vector<SVGChar>::iterator itSearch = charIt + 1;
            Vector<SVGChar>::iterator endSearch = charIt + range.endOffset - i;
            while (itSearch != endSearch) {
                // No need to check for 'isHidden()' here as this function is not called for text paths.
                if (itSearch->drawnSeperated)
                    break;

                itSearch++;
            }

            unsigned int positionOffset = itSearch - charIt;

            // Calculate width/height of subrange
            SVGInlineBoxCharacterRange subRange;
            subRange.box = range.box;
            subRange.startOffset = i;
            subRange.endOffset = i + positionOffset;

            if (calcWidthOnly)
                length += cummulatedWidthOfInlineBoxCharacterRange(subRange);
            else
                length += cummulatedHeightOfInlineBoxCharacterRange(subRange);

            // Calculate gap between the previous & current range
            // <text x="10 50 70">ABCD</text> - we need to take the gaps between A & B into account
            // so add "40" as width, and analogous for B & C, add "20" as width.
            if (itSearch > chunk.start && itSearch < chunk.end) {
                SVGChar& lastCharacter = *(itSearch - 1);
                SVGChar& currentCharacter = *itSearch;

                int offset = box->direction() == RTL ? box->end() - i - positionOffset + 1 : box->start() + i + positionOffset - 1;

                // FIXME: does this need to change to handle multichar glyphs?
                int charsConsumed = 1;
                String glyphName;
                if (calcWidthOnly) {
                    float lastGlyphWidth = box->calculateGlyphWidth(style, offset, 0, charsConsumed, glyphName);
                    length += currentCharacter.x - lastCharacter.x - lastGlyphWidth;
                } else {
                    float lastGlyphHeight = box->calculateGlyphHeight(style, offset, 0);
                    length += currentCharacter.y - lastCharacter.y - lastGlyphHeight;
                }
            }

            // Advance processed characters
            i += positionOffset - 1;
            charIt = itSearch;
        }
    }

    ASSERT(charIt == chunk.end);
    return length;
}

static float cummulatedWidthOfTextChunk(SVGTextChunk& chunk)
{
    return cummulatedWidthOrHeightOfTextChunk(chunk, true);
}

static float cummulatedHeightOfTextChunk(SVGTextChunk& chunk)
{
    return cummulatedWidthOrHeightOfTextChunk(chunk, false);
}

static float calculateTextAnchorShiftForTextChunk(SVGTextChunk& chunk, ETextAnchor anchor)
{
    float shift = 0.0f;

    if (chunk.isVerticalText)
        shift = cummulatedHeightOfTextChunk(chunk);
    else
        shift = cummulatedWidthOfTextChunk(chunk);

    if (anchor == TA_MIDDLE)
        shift *= -0.5f;
    else
        shift *= -1.0f;

    return shift;
}

static void applyTextAnchorToTextChunk(SVGTextChunk& chunk)
{
    // This method is not called for chunks containing chars aligned on a path.
    // -> all characters are visible, no need to check for "isHidden()" anywhere.

    if (chunk.anchor == TA_START)
        return;

    float shift = calculateTextAnchorShiftForTextChunk(chunk, chunk.anchor);

    // Apply correction to chunk
    Vector<SVGChar>::iterator chunkIt = chunk.start;
    for (; chunkIt != chunk.end; ++chunkIt) {
        SVGChar& curChar = *chunkIt;

        if (chunk.isVerticalText)
            curChar.y += shift;
        else
            curChar.x += shift;
    }

    // Move inline boxes
    Vector<SVGInlineBoxCharacterRange>::iterator boxIt = chunk.boxes.begin();
    Vector<SVGInlineBoxCharacterRange>::iterator boxEnd = chunk.boxes.end();

    for (; boxIt != boxEnd; ++boxIt) {
        SVGInlineBoxCharacterRange& range = *boxIt;

        InlineBox* curBox = range.box;
        ASSERT(curBox->isInlineTextBox());

        // Move target box
        if (chunk.isVerticalText)
            curBox->setY(curBox->y() + static_cast<int>(shift));
        else
            curBox->setX(curBox->x() + static_cast<int>(shift));
    }
}

static float calculateTextLengthCorrectionForTextChunk(SVGTextChunk& chunk, ELengthAdjust lengthAdjust, float& computedLength)
{
    if (chunk.textLength <= 0.0f)
        return 0.0f;

    float computedWidth = cummulatedWidthOfTextChunk(chunk);
    float computedHeight = cummulatedHeightOfTextChunk(chunk);

    if ((computedWidth <= 0.0f && !chunk.isVerticalText) ||
        (computedHeight <= 0.0f && chunk.isVerticalText))
        return 0.0f;

    if (chunk.isVerticalText)
        computedLength = computedHeight;
    else
        computedLength = computedWidth;

    if (lengthAdjust == SVGTextContentElement::LENGTHADJUST_SPACINGANDGLYPHS) {
        if (chunk.isVerticalText)
            chunk.ctm.scaleNonUniform(1.0f, chunk.textLength / computedLength);
        else
            chunk.ctm.scaleNonUniform(chunk.textLength / computedLength, 1.0f);

        return 0.0f;
    }

    return (chunk.textLength - computedLength) / float(chunk.end - chunk.start);
}

static void applyTextLengthCorrectionToTextChunk(SVGTextChunk& chunk)
{
    // This method is not called for chunks containing chars aligned on a path.
    // -> all characters are visible, no need to check for "isHidden()" anywhere.

    // lengthAdjust="spacingAndGlyphs" is handled by modifying chunk.ctm
    float computedLength = 0.0f;
    float spacingToApply = calculateTextLengthCorrectionForTextChunk(chunk, chunk.lengthAdjust, computedLength);

    if (!chunk.ctm.isIdentity() && chunk.lengthAdjust == SVGTextContentElement::LENGTHADJUST_SPACINGANDGLYPHS) {
        SVGChar& firstChar = *(chunk.start);

        // Assure we apply the chunk scaling in the right origin
        TransformationMatrix newChunkCtm;
        newChunkCtm.translate(firstChar.x, firstChar.y);
        newChunkCtm = chunk.ctm * newChunkCtm;
        newChunkCtm.translate(-firstChar.x, -firstChar.y);

        chunk.ctm = newChunkCtm;
    }

    // Apply correction to chunk 
    if (spacingToApply != 0.0f) {
        Vector<SVGChar>::iterator chunkIt = chunk.start;
        for (; chunkIt != chunk.end; ++chunkIt) {
            SVGChar& curChar = *chunkIt;
            curChar.drawnSeperated = true;