Use include/osgQt also for osgQt5

[manisandro]

As a followup to b7d1d03, since the osgQt4 and osgQt5 headers are identical, I think it is better to use include/osgQt also for osgQt5, given that most osgQt consumers include their headers via #include <osgQt/...>.

[manisandro]

Scratch that, there is #define OSGQT_QT_VERSION in osgQt/Version. The only other solution I see is following the convention a number of packages/distros use in installing the headers to include/qt5/<package>. This means that consumers might need to tweak their build scripts, but at least the #includes can remain the same.

[manisandro]

Or maybe one can do without OSGQT_QT_VERSION and keep the headers identical? Given that the library names now differ, the risk of mixing up qt versions is pretty small.

[manisandro]

So I actually think that include/osgQt for both qt4 and qt5 and dropping osgQt/Version is the least invasive option.

[marache]

Hi @manisandro
Does that mean that you can't have both Qt4 and Qt5 headers intalled at the same time ?

[manisandro]

@marache Well the headers are identical for both Qt4 and Qt5, so it is merely a question how you deal with packaging them. RPM supports file co-ownership, meaning that multiple packages can own the same file as long as the file is identical. I'm not sure if DEB supports something similar, but if not you can still have a subpackage common to both Qt4 and Qt5 which pulls in the headers.