Excellent!  My favorite kinds of problems are those that are solved
without my input.  :)

On 5/13/10 9:39 AM, Flo wrote:
> Dear all, 
> 
> For the use of further VirtualGL users, here are my answers (if it can be
> called so) to the problem I had:
> 
> In paintEvent(QPaintEvent *e) we were calling swapBuffers();
> 
> However, in nokia' documentation, i twas stated that:
> http://doc.qt.nokia.com/4.6/qglwidget.html#swapBuffers
> <<void QGLWidget::setAutoBufferSwap ( bool on )   [protected]>>
> If on is true and the widget is using a double-buffered format, the
> background and foreground GL buffers will automatically be swapped after
> each paintGL() call.
> The buffer auto-swapping is on by default.
> 
> This means we were actually re-swapping the buffer. Although this had no
> effect locally, it had a huge negative impact with VirtualGL (that actually
> helped us realize our mistake).
> 
> Simply removing the unjustified call to the additional swapBuffers() solved
> our problem.
> 
> As such, VirtualGL 2.2alpha is working perfectly well.
> Regards,
> 
> -----Original Message-----
> From: DRC [mailto:[email protected]] 
> Sent: Sunday, April 11, 2010 7:30 PM
> To: [email protected]
> Subject: Re: [VirtualGL-Users] QT + VirtualGL = black viewport flickering -
> no display
> 
> There should not be a significant performance change in VGL 2.2 alpha,
> and in fact some users have observed it to be faster than previous
> releases.  We are no longer using TurboJPEG/IPP, but we are using
> libjpeg-turbo, which is a fully open source codec with approximately the
> same performance.
> 
> With 2.2 alpha, you can set VGL_LOGO=1 to verify that VirtualGL is
> indeed activated (if so, it will display a VGL logo in the lower right
> corner of the 3D rendering area.)
> 
> On 4/11/10 4:27 PM, Flo wrote:
>> I built a small app over the week-end ... to realize that it does not
>> reproduce the issue.
>> Every Qt openGL code and mine is running, but the app I want.
>>
>> However, I find a previous version of our app that is working (only with
>> VirtualGL 2.2alpha, seg fault with any other previous versions). I know we
>> did some speed improvement regarding Qt pixmap issues so I will dig into
>> that and let the mailinglist know as soon as I found which one of our
>> "improvements" caused this prob.
>>
>> I will send a small app reproducing the issue as soon as I found which
> part
>> of the code creates it.
>>
>> Now, the version of our app that works with VirtualGL2.2alpha is very
> slow.
>> Checking the release notes I saw you are not using the TurboJpeg anymore.
> Is
>> there a known decrease in performance with this change ? (glxgears is not
>> slow at all ... only our app .... again !)
>>
>> Best regards and thanks for the quick replies.
>>
>> Flo.
>>
>> -----Original Message-----
>> From: DRC [mailto:[email protected]] 
>> Sent: Friday, April 09, 2010 1:52 AM
>> To: VirtualGL Users
>> Subject: Re: [VirtualGL-Users] QT + VirtualGL = black viewport flickering
> -
>> no display
>>
>> I'm not sure it is the same issue.  Alex's issue was specific to MITK,
>> and he was able to resolve it by upgrading to a new version.
>>
>> Does your app use VTK or Qt or both?  Is it something that could be
>> reproduced with a simple test application that I could build and run here?
>>
>> On 4/8/10 10:24 PM, Flo wrote:
>>> Dear All,
>>>
>>> I have an issue that was previously reported on you mailinglist here and
>>> not answered:
>>>
>>
> _http://sourceforge.net/mailarchive/message.php?msg_id=cbb4c0f20802191246o28
>> [email protected]_
>>>
>>> Specifically, I have a Qt application that uses 2D and 3D rendering in
>>> viewports. Although fine as standalone, when used through VirtualGL,
>>> every viewport (2D or 3D) is black. The only moment when I can see the
>>> proper content is by creating a mouse event (movement, click and else),
>>> where it flickers and for a second I can see the proper content before
>>> it becomes black again.
>>>
>>> I tried many combination of VirtualGL options but it seems not to do any
>>> good.
>>>
>>> The VirtualGL server is a SLED 11, although using few Suse OSS 11.2
>>> repo, 64-bits and NVidia video card.
>>>
>>> "from what have been said: It sounds like if the
>>>
>>> OpenGL buffer is not flushed properly.
>>>
>>> We are also aware of problems with some OpenGL drivers, beside the
>>>
>>> ones from Nvidia, where setting the VTK rendering mode to "immediate"
>>>
>>> may help."
>>>
>>> But it didn't go any further in the thread.
>>>
>>> Any help would be greatly appreciated.
>>>
>>> Flo.
>>>
>>>
>>>
>>>
>>
> ----------------------------------------------------------------------------
>> --
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>>>
>>>
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>>
>>
> ----------------------------------------------------------------------------
>> --
>> Download Intel&#174; Parallel Studio Eval
>> Try the new software tools for yourself. Speed compiling, find bugs
>> proactively, and fine-tune applications for parallel performance.
>> See why Intel Parallel Studio got high marks during beta.
>> http://p.sf.net/sfu/intel-sw-dev
>> _______________________________________________
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>>
>>
>>
> ----------------------------------------------------------------------------
> --
>> Download Intel&#174; Parallel Studio Eval
>> Try the new software tools for yourself. Speed compiling, find bugs
>> proactively, and fine-tune applications for parallel performance.
>> See why Intel Parallel Studio got high marks during beta.
>> http://p.sf.net/sfu/intel-sw-dev
>> _______________________________________________
>> VirtualGL-Users mailing list
>> [email protected]
>> https://lists.sourceforge.net/lists/listinfo/virtualgl-users
> 
> ----------------------------------------------------------------------------
> --
> Download Intel&#174; Parallel Studio Eval
> Try the new software tools for yourself. Speed compiling, find bugs
> proactively, and fine-tune applications for parallel performance.
> See why Intel Parallel Studio got high marks during beta.
> http://p.sf.net/sfu/intel-sw-dev
> _______________________________________________
> VirtualGL-Users mailing list
> [email protected]
> https://lists.sourceforge.net/lists/listinfo/virtualgl-users
> 
> 
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