Subscript text in painter->drawTExt(..)

[Uwe]

void drawRichText(QPainter *painter, const QRect &rect, int flags, QTextDocument &text)
{
    text.setPageSize(QSize(rect.width(), QWIDGETSIZE_MAX));
 
    QAbstractTextDocumentLayout* layout = text.documentLayout();
 
    const int height = qRound(layout->documentSize().height());
    int y = rect.y();
    if (flags & Qt::AlignBottom)
        y += (rect.height() - height);
    else if (flags & Qt::AlignVCenter)
        y += (rect.height() - height)/2;
 
    QAbstractTextDocumentLayout::PaintContext context;
    context.palette.setColor(QPalette::Text, painter->pen().color());
 
    painter->save();
 
    painter->translate(rect.x(), y);
    layout->draw(painter, context);
 
    painter->restore();
}

void drawRichText(QPainter *painter, const QRect &rect, int flags, QTextDocument &text)
{
    text.setPageSize(QSize(rect.width(), QWIDGETSIZE_MAX));

    QAbstractTextDocumentLayout* layout = text.documentLayout();

    const int height = qRound(layout->documentSize().height());
    int y = rect.y();
    if (flags & Qt::AlignBottom)
        y += (rect.height() - height);
    else if (flags & Qt::AlignVCenter)
        y += (rect.height() - height)/2;

    QAbstractTextDocumentLayout::PaintContext context;
    context.palette.setColor(QPalette::Text, painter->pen().color());

    painter->save();

    painter->translate(rect.x(), y);
    layout->draw(painter, context);

    painter->restore();
}

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If you need additional operations like heightForWidth() or textSize() you can have a look at the implementation of QwtRichTextEngine in the Qwt package.

And yes, you can ask yourself, why you have to write this strange code for such a simple task.

HTH,
Uwe