OpenGL vs. Qt4 OpenGL

[Allen Winter]

On Friday 14 December 2007 02:48:44 Matthias Kretz wrote:
> On Friday 14 December 2007, Andreas Pakulat wrote:
> > On 13.12.07 17:53:49, Allen Winter wrote:
> > > kpat links against ${QT_QTOPENGL_LIBRARY}, which points to
> > > qt-copy/lib/libQtOpenGL.so
> > >
> > > so this is why I'm confused.  I do have 2 separate OpenGL builds
> > > available.
> > >
> > > should we permit stuff to build against QT_QTOPENGL?
> > > so far, the only instance I've seen of this is in kpat
> >
> > I'm not into that stuff that much, but I think things like kwin that
> > want to render directly onto the screen with OpenGL need to link only
> > against libGL, not against libQtOpenGL.
> >
> > If an app however only wants to display an OpenGL scene inside a QWidget
> > then it primarly needs QtOpenGL. (the libGL is automatically pulled in
> > through the deps).
> 
> Just a small correction...
> 
> there are basically three cases for Qt apps with GL:
> 
> a) using only libGL (e.g. kwin)
> b) using only libQtOpenGL (e.g. an application that just wants QPainter to use 
> OpenGL internally)
> c) using both libGL and libQtOpenGL (e.g. an app that uses OpenGL calls for a 
> QGLWidget)
> 
> a) needs ${OPENGL_gl_LIBRARY}
> b) needs ${QT_QTOPENGL_LIBRARY}
> c) needs ${QT_QTOPENGL_LIBRARY} ${OPENGL_gl_LIBRARY}
> 

Thanks Andreas and Matthias for clearing up my confusion.

-Allen