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olidem
14th January 2012, 16:16
Hi :)

I have developed an application under Qt 4.5.2, which still runs fine.
Unfortunately I have not found the time so far to port it to a newer Qt-Version.

Today, I installed my app on a new Windows 7 machine which has

onchip Intel HD graphics.

Now, I encounter an incorrect refreshing-behaviour
of my QGraphicsView with underlying OpenGL viewport
(just on this machine, with newest Intel drivers):

I show a usual QWidget as window above my
QGraphicsView (so the widget overlaps the view partly).
If I then close this window, the view only refreshes those parts
which werer hidden behind the window.
The other parts of the view are "over-painted".

Again: on all other machines I have tested so far, this does happen.

I also tried to update manually the view, the scene the items, and also
the GLWidget, without success.

Do you know about any problems with Intel HD graphics controllers?

Best regards and many thanks in advance!

Olli

jh
20th January 2012, 22:47
hi,

i'm sorry, i cannot help with this problem but i can confirm that the intel HD cards are really buggy.
for instance we discovered that writing to the color buffer and reading the same pixles (OpenGL) do not get the same results.
you cannot see this when you just look at the rendered pictures but we use a backbuffer to select items in a view
by rendering them with the ID of an object translated to a color. since the color is not correct, we do get
wrong objects.
we do not have a solution nor any reply by intel (we posted on the intel forum some weeks ago).
we do not have this problem with ati or nvidia cards so we recommend to our customers
to have a 'real' graphics card and not just those things which intel calls a graphics card.

regards