[Qt-interest] invalid drawable with Cocoa/QGLWidget

[Alan Norton]

Thanks, Oliver. 
I have a bit more information.  This problem seems to only occur if the 
qglwidget is not visible when it first gets a paintEvent().  In my 
example the qglwidget is scrolled out of view when its containing widget 
first is shown.  I suspect that Qt is creating the OpenGL context right 
before or right after the containing widget gets the first paintEvent(), 
but I don't know how to intercept this before it fails.
-Alan
Oliver.Knoll at comit.ch wrote:
> Alan Norton wrote on Thursday, February 25, 2010 6:03 PM:
>
>   
>> With Cocoa on Mac OSX10.5, I get a message "invalid drawable" (and a
>> defective image) whenever my QGLWidget redraws.  
>>     
>
> I can confirm that I use a QGLWidget with Qt 4.6 binary build Cocoa on Mac OS 10.6.2 without problems :) I know, that is little help to your problem, but it might make the "future" a bit brighter ;) (and be a strong hint that the problem really seems to be in the GL driver shipped with Mac OS 10.5 or wherever, assuming that you are also using the latest Qt 4.6.x).
>
> The stuff which is drawn is admittedly very simple: 2 triangles with a texture on it, using Qt shader programs (so basically I draw a "photo" ;)
>
> Cheers, Oliver
>