mouse scrolling zoom patch

[Peter Kümmel]

Stephan, Qt 4.7 could not compile lines like this:

    zoom &= !(ev->modifiers() & (Qt::ShiftModifier || Qt::AltModifier));

It mixes flag (&,|) and bool (&&,||) operations, so do you mean

    zoom &= !(ev->modifiers() & (Qt::ShiftModifier | Qt::AltModifier));
or
    zoom &= !(ev->modifiers() && (Qt::ShiftModifier || Qt::AltModifier));

Peter