QTextDocument: Support for vertical alignment in points

It would be very helpful for me if in QTextDocument it was possible to change the vertical alignment of a text passage (i.e. QTextFragment) in detail in pt units.

In HTML e.g. you would write:

<p>Hello<br>
Hello<span style='vertical-align:-5pt;'>Hello deep</span>
<br>Hello Hello Hello Hello</p>

what should be rendered in this way:

I know there is a method setVerticalAlignment in QTextCharFormat, but this can only handle with some special modes (top, bottom, ...). What I'm missing is a function to specify the alignment in pt (> 0 -> higher; < 0 -> deeper). The size of the font should not change, only the alignment.

I can't usw QtWebKit because it isn't supported on iOS und Android ... so would be very nice to integrate this feature into QTextDocument!

Best, Christian