C++ SVGInlineTextBox::renderer方法代码示例

void SVGTextChunkBuilder::addTextChunk(Vector<SVGInlineTextBox*>& lineLayoutBoxes, unsigned boxStart, unsigned boxCount)
{
    SVGInlineTextBox* textBox = lineLayoutBoxes[boxStart];
    ASSERT(textBox);

    const RenderStyle* style = textBox->renderer().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(textBox->renderer().parent())) {
        SVGLengthContext lengthContext(textContentElement);
        desiredTextLength = textContentElement->specifiedTextLength().value(lengthContext);

        switch (textContentElement->lengthAdjust()) {
        case SVGLengthAdjustUnknown:
            break;
        case SVGLengthAdjustSpacing:
            chunkStyle |= SVGTextChunk::LengthAdjustSpacing;
            break;
        case SVGLengthAdjustSpacingAndGlyphs:
            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);
}

static inline void reverseInlineBoxRangeAndValueListsIfNeeded(void* userData, Vector<InlineBox*>::iterator first, Vector<InlineBox*>::iterator last)
{
    ASSERT(userData);
    Vector<SVGTextLayoutAttributes*>& attributes = *reinterpret_cast<Vector<SVGTextLayoutAttributes*>*>(userData);

    // This is a copy of std::reverse(first, last). It additionally assures that the metrics map within the renderers belonging to the InlineBoxes are reordered as well.
    while (true)  {
        if (first == last || first == --last)
            return;

        if (!(*last)->isSVGInlineTextBox() || !(*first)->isSVGInlineTextBox()) {
            InlineBox* temp = *first;
            *first = *last;
            *last = temp;
            ++first;
            continue;
        }

        SVGInlineTextBox* firstTextBox = toSVGInlineTextBox(*first);
        SVGInlineTextBox* lastTextBox = toSVGInlineTextBox(*last);

        // Reordering is only necessary for BiDi text that is _absolutely_ positioned.
        if (firstTextBox->len() == 1 && firstTextBox->len() == lastTextBox->len()) {
            RenderSVGInlineText& firstContext = firstTextBox->renderer();
            RenderSVGInlineText& lastContext = lastTextBox->renderer();

            SVGTextLayoutAttributes* firstAttributes = 0;
            SVGTextLayoutAttributes* lastAttributes = 0;
            findFirstAndLastAttributesInVector(attributes, &firstContext, &lastContext, firstAttributes, lastAttributes);
            swapItemsInLayoutAttributes(firstAttributes, lastAttributes, firstTextBox->start(), lastTextBox->start());
        }

        InlineBox* temp = *first;
        *first = *last;
        *last = temp;

        ++first;
    }
}

static inline void dumpTextBoxes(Vector<SVGInlineTextBox*>& boxes)
{
    unsigned boxCount = boxes.size();
    fprintf(stderr, "Dumping all text fragments in text sub tree, %i boxes\n", boxCount);

    for (unsigned boxPosition = 0; boxPosition < boxCount; ++boxPosition) {
        SVGInlineTextBox* textBox = boxes.at(boxPosition);
        Vector<SVGTextFragment>& fragments = textBox->textFragments();
        fprintf(stderr, "-> Box %i: Dumping text fragments for SVGInlineTextBox, textBox=%p, textRenderer=%p\n", boxPosition, textBox, textBox->renderer());
        fprintf(stderr, "        textBox properties, start=%i, len=%i, box direction=%i\n", textBox->start(), textBox->len(), textBox->direction());
        fprintf(stderr, "   textRenderer properties, textLength=%i\n", textBox->renderer()->textLength());

        const UChar* characters = textBox->renderer()->characters();

        unsigned fragmentCount = fragments.size();
        for (unsigned i = 0; i < fragmentCount; ++i) {
            SVGTextFragment& fragment = fragments.at(i);
            String fragmentString(characters + fragment.characterOffset, fragment.length);
            fprintf(stderr, "    -> Fragment %i, x=%lf, y=%lf, width=%lf, height=%lf, characterOffset=%i, length=%i, characters='%s'\n"
                          , i, fragment.x, fragment.y, fragment.width, fragment.height, fragment.characterOffset, fragment.length, fragmentString.utf8().data());
        }
    }
}

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 charsConsumed = 0;
                float glyphWidth = 0.0f;
                float glyphHeight = 0.0f;
                String glyphName;
                String unicodeString;
                box->measureCharacter(style, i + positionOffset - 1, charsConsumed, glyphName, unicodeString, glyphWidth, glyphHeight);

                if (calcWidthOnly)
                    length += currentCharacter.x - lastCharacter.x - glyphWidth;
                else
                    length += currentCharacter.y - lastCharacter.y - glyphHeight;
            }

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

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