Example #1
0
PositionWithAffinity LayoutSVGInlineText::positionForPoint(const LayoutPoint& point)
{
    if (!hasTextBoxes() || !textLength())
        return createPositionWithAffinity(0);

    ASSERT(m_scalingFactor);
    float baseline = m_scaledFont.getFontMetrics().floatAscent() / m_scalingFactor;

    LayoutBlock* containingBlock = this->containingBlock();
    ASSERT(containingBlock);

    // Map local point to absolute point, as the character origins stored in the text fragments use absolute coordinates.
    FloatPoint absolutePoint(point);
    absolutePoint.moveBy(containingBlock->location());

    float closestDistance = std::numeric_limits<float>::max();
    float closestDistancePosition = 0;
    const SVGTextFragment* closestDistanceFragment = nullptr;
    SVGInlineTextBox* closestDistanceBox = nullptr;

    for (InlineTextBox* box = firstTextBox(); box; box = box->nextTextBox()) {
        if (!box->isSVGInlineTextBox())
            continue;

        SVGInlineTextBox* textBox = toSVGInlineTextBox(box);
        for (const SVGTextFragment& fragment : textBox->textFragments()) {
            FloatRect fragmentRect = fragment.boundingBox(baseline);

            float distance = 0;
            if (!fragmentRect.contains(absolutePoint))
                distance = fragmentRect.squaredDistanceTo(absolutePoint);

            if (distance <= closestDistance) {
                closestDistance = distance;
                closestDistanceBox = textBox;
                closestDistanceFragment = &fragment;
                closestDistancePosition = fragmentRect.x();
            }
        }
    }

    if (!closestDistanceFragment)
        return createPositionWithAffinity(0);

    int offset = closestDistanceBox->offsetForPositionInFragment(*closestDistanceFragment, LayoutUnit(absolutePoint.x() - closestDistancePosition), true);
    return createPositionWithAffinity(offset + closestDistanceBox->start(), offset > 0 ? VP_UPSTREAM_IF_POSSIBLE : TextAffinity::Downstream);
}