On 02/13/2012 01:50 AM, ext Jon Trulson wrote: > Hi, I'm building Qt5 (latest from git) on an arm board (imx53 QSB). I > am not using X11. I am using the eglfs plugin. > > I have attempted to run several of the qtbase demos (like > animatedtiles). In all cases, I get a SEGV in > qpaintengineex_opengl2.cpp:1960 (QGL2PaintEngineEx::begin()). > > This code looks like: > 1959: d->ctx = d->device->context(); > 1960: d->ctx->d_ptr->active_engine = this; > > d->device->context() is returning NULL, and of course it then cores > when it tries to deref it on line 1960. > > I have gone through the eglfs plugin code in as much detail as I can - > The egl display and window surfaces are being created and initialized > properly, and seem to return sane values. The eglCreateContext() > calls in qeglplatformcontext.cpp are working and returning sane > results. > > So - where/when is this QGLContext supposed to be created? And why is > it not being created :) > > I am very new to the guts of Qt, so please forgive me if I'm missing > something stupid. Any ideas or suggestions are definitely welcome. > > Thanks. > > > PS: I case it's useful, here are a few lines from the backtrace in > gdb (frame #1 is where the trouble is): > > #0 0x2c4eb7f4 in QScopedPointer<QGLContextPrivate, > QScopedPointerDeleter<QGLContextPrivate> >::operator-> (this=0x4) > at ../../include/QtCore/../../src/corelib/tools/qscopedpointer.h:109 > #1 0x2c520cd8 in QGL2PaintEngineEx::begin (this=0x358d8, pdev=0x355a8) > at gl2paintengineex/qpaintengineex_opengl2.cpp:1960 > #2 0x2b68c558 in QPainter::begin (this=0x7eedf430, pd=0x355a8) > at painting/qpainter.cpp:1826 > #3 0x2b68ab28 in QPainter (this=0x7eedf430, pd=0x2f868) > at painting/qpainter.cpp:1470 > #4 0x2ac371b0 in QWidgetPrivate::drawWidget (this=0x2f878, pdev=0x355a8, > rgn=@0x7eedf550, offset=@0x7eedf59c, flags=4, sharedPainter=0x0, > backingStore=0x35350) at kernel/qwidget.cpp:5091 > > I have more if you like :)
I'd recommend trying qmlscene or examples/opengl/hellowindow --single here as well, as I'm not sure eglfs supports multiple top-levels. A QGLWidget embedded in a widget hierarchy will always force a top-level platform window to be created, since it needs its own EGLSurface (or similar on other platforms). -- Samuel _______________________________________________ Interest mailing list Interest@qt-project.org http://lists.qt-project.org/mailman/listinfo/interest
