qt 4.8.2 qpa QGraphicsView ( QGLWidget ) rendering produces black screen

Question

I'm trying to render some simple qt application, that uses QGraphicsView with QGLWidget as a viewport ( slightly modified collidingmice ) on armv7 embedded platform ( beagleboard ). Starting application like this:

collidingmice -platform eglfs

But screen is always remains dark. ( textures example is working fine ). Is qt lighthouse able to render painting throught opengles with platform like elgfs? I can't find any precise information about it.
Thanks in Advance.

Answer 1

I just had a look to the sources here. The driver is not making any assumptions on your windows system, so it is using 0 as the default native window handle, which is often correct. This may not be the case for your platform. You'll have to modify the sources so that the function eglCreateWindowSurface is passed a valid native window handle. I suspect that might be the reason of the black screen.

EDIT: I don't know what exactly that library libpvrPVR2D_FRONTWSEGL.so does, but according to the name that may be what will provide the native window on the framebuffer. Read the manual of that library.

EDIT2: That library provides in fact the Window System. Look here: http://processors.wiki.ti.com/index.php/SGXDbg. You could also use Qt Embedded instead of Qt QPA as there is a working driver for the PowerVR: http://qt.gitorious.org/qt/qt/trees/4.8/src/plugins/gfxdrivers/powervr.