The QGLContext class encapsulates an OpenGL rendering context. ... QGLContext  ( const QGLFormat & format, QPaintDevice * device )  . ... bool  create  ( const QGLContext * shareContext = 0 )  . ... Constructs an OpenGL context for the paint device device, which must be a widget or a pixmap. ... Returns TRUE if it was successful in creating a context that satisfies the requested format , otherwise FALSE is returned (the context is invalid). ... Sets a new OpenGL context specification format. ...