[PyQt] Rendering unicode 0x1D122 on Linu

[Phil Thompson]

On Wed, 5 Aug 2009 15:24:33 +0100, Peter Howard
<peterhoward42 at googlemail.com> wrote:
> Hi Phil,
> 
> 
> 
> I wonder if you can shed any light on this problem – or suggest
> diagnostic
> steps.
> 
> 
> 
> The program below successfully renders the bass cleff musical symbol on a
> Windows/PyQt installation:
> 
> 
> 
> from PyQt4.QtGui import *
> 
> from PyQt4.QtCore import *
> 
> local_app = QApplication([])
> 
> buf = u"<font style='font-family: Euterpe; font-size:
> 40px;'>\U0001D122</font>"
> 
> lbl = QLabel()
> 
> lbl.setText(buf)
> 
> lbl.show()
> 
> local_app.exec_()
> 
> 
> 
> The same program on a Linux installation runs without complaint, but
shows
> a
> different character in place of the expected bass cleff symbol (I don't
> know
> what it is).
> 
> 
> Of course this is dependent on the cited font being available. In both
> cases
> I have intalled the Euterpre truetype font:
> http://openfontlibrary.org/media/files/Eimai/191
> 
> 
> I have attempted to prove the successful installation of this font on the
> Linux machine using the Gnome Character Map application. This sucessfully
> shows a bunch of musical symbols in the preview pane when the Euterpre
font
> is selected, and with the music symbols unicode block selected. If I
> uninstall/reinstall the font, this application's ability to preview the
> musical symbols disappears / reappears accordingly. So it seems the font
is
> viable and available.
> 
> 
> You will see that the unicode code point in question is > 0xFFFF, ie
beyond
> the basic multilingual plane, and thus requires surrogate-pair
> representation in Python. (std build)
> 
> 
> I have tried to reproduce the problem in straight C++ Qt (to rule out
PyQt)
> , but have fallen near the finishing post.
> 
> 
> The program below is I believe equivalent to the Python - and this builds
> and runs as expected. However my hurdle is that I am not confident about
> how
> to insert the unicode string literal into the C++, and thus cannot quite
> finish the job.
> 
> 
> #include <QApplication>
> #include <QLabel>
> 
> int main(int argc, char *argv[])
>     {
>     QApplication app(argc, argv);
>     QString s("<font style='font-family: Euterpe; font-size: 40px;'>plain
> text</font>");
>     QLabel label(s);
>     label.show();
>     return app.exec();
>     }
> 
> 
> The Linux machine environment is: Ubuntu 9.04. Qt 4.5.0, Python 2.6, PyQt
> 4.5.4
> 
> 
> Any advice gratefully received.

Works fine for me with a self built Python 2.6, Qt 4.5.2 and current SIP
and PyQt snapshots (I don't think the snapshots will make a difference).

It doesn't work with the standard Kubuntu Python, Qt, SIP and PyQt
packages. That seems to suggest the problem is either with Ubuntu's build
of Python or Qt.

Phil