Function findSplitPositionForChar

core/ui/UIRichText.cpp:2001–2054

}

int findSplitPositionForChar(Label* label,
                             const StringUtils::StringUTF8& text,
                             int estimatedIdx,
                             float originalLeftSpaceWidth,
                             float newLineWidth)
{
    bool startingNewLine = (newLineWidth == originalLeftSpaceWidth);

    int stringLength = static_cast<int>(text.length());
    int leftLength   = estimatedIdx;

    // The adjustment of the new line position
    std::string leftStr = text.getAsCharSequence(0, leftLength);
    label->setString(leftStr);
    float textRendererWidth = label->getContentSize().width;
    if (originalLeftSpaceWidth < textRendererWidth)  // Have protruding
    {
        while (leftLength-- > 0)
        {
            // try to erase a char
            auto& ch = text.getString().at(leftLength);
            leftStr.erase(leftStr.end() - ch._char.length(), leftStr.end());
            label->setString(leftStr);
            textRendererWidth = label->getContentSize().width;
            if (textRendererWidth <= originalLeftSpaceWidth)  // is fitted
                break;
        }
    }
    else if (textRendererWidth < originalLeftSpaceWidth)  // A wide margin
    {
        while (leftLength < stringLength)
        {
            // try to append a char
            auto& ch = text.getString().at(leftLength);
            ++leftLength;
            leftStr.append(ch._char);
            label->setString(leftStr);
            textRendererWidth = label->getContentSize().width;
            if (originalLeftSpaceWidth < textRendererWidth)  // protruded, undo add
            {
                --leftLength;
                break;
            }
            else if (originalLeftSpaceWidth == textRendererWidth)  // quite fit
            {
                break;
            }
        }
    }

    if (leftLength <= 0)
        return (startingNewLine) ? 1 : 0;
    return leftLength;
}
}  // namespace

void RichText::handleTextRenderer(std::string_view text,