[Interest] [Qt3D] Ununderstable message when closing a scene

[Sean Harmer]

Hi,

On Friday 17 June 2016 12:11:56 Xavier Bigand wrote:
> I finally found a work around to fix my crash when loading models
> after few unload.
> 
> I simply release myself all children of the delete entity with the
> following recursive method :
> 
> 
>     void    releaseModel(Qt3DCore::QNode& model)
> 
>     {
> 
>         QEntity*    entity = dynamic_cast<QEntity*>(&model);
> 
> 
>         if (entity)
> 
>         {
> 
>             QComponentVector    components = entity->components();
> 
> 
>             foreach (QComponent* component, components)
> 
>             {
> 
>                 entity->removeComponent(component);
> 
>                 delete component;
> 
>             }
> 
>         }
> 
> 
>         QNodeVector nodes = model.childNodes();
> 
> 
>         foreach (QNode* node, nodes)
> 
>         {
> 
>             releaseModel(*node);
> 
>             delete node;
> 
>         }
> 
>     }
> 
> 
> 
> I don't know why I haven't the same behavior when letting Qt doing it.
> 
> 
> 
> Need I fill a bug?

Yes, please file a JIRA. Ideally with a test case. Also for any leaks you 
suspect.

Thanks,

Sean

> 
> 
> 
> It seems that Qt3D have a lot of memory leaks, after changing a few
> projects our application use more than 1Go when with our actual 3D engine
> it's always lower than 200Mo.
> 
> 2016-06-16 23:03 GMT+02:00 Xavier Bigand <flamaros.xavier at gmail.com>:
> > Thank for the report.
> > 
> > I was not sure if it wasn't me doing something wrong.
> > 
> > But it might be the case, because the assert seems to come from a bad
> > ressources management.
> > When I switch projects I simply delete entities that attached to the root
> > one, but doing this leads to the assert at a certain time and memory leaks
> > apparently.
> > 
> > My scenes are composed of objects that I load from a custom file format,
> > it's for an architecture software.
> > 
> > I can load 2 projects in a row, and on the third I get the assert.
> > 
> > It seems that I can debug when using Visual instead of QtCreator. And it
> > surprise me because the release of ressources seems to be done later than
> > when I call the delete of entities.
> > 
> > 2016-06-16 21:14 GMT+02:00 Harald Vistnes <harald.vistnes at gmail.com>:
> >> I get the same QMetaProperty::read warning. I just filed a Jira for it.
> >> https://bugreports.qt.io/browse/QTBUG-54159?filter=17174
> >> 
> >> Annoying and it came recently, but not critical as you can continue
> >> running the debugger.
> >> 
> >> Harald
> >> 
> >> 2016-06-16 17:53 GMT+02:00 Xavier Bigand <flamaros.xavier at gmail.com>:
> >>> Sometimes when it doesn't crash on the first scene switch I can get this
> >>> assert :
> >>> ASSERT: "m_entries[index].m_counter == handle.counter()" in file
> >>> c:/Users/qt/work/qt/qt3d/src/core/resources/qhandlemanager_p.h, line 170
> >>> 
> >>> Sadly it seems that I am not able to debug it with source code.
> >>> 
> >>> 2016-06-16 17:35 GMT+02:00 Xavier Bigand <flamaros.xavier at gmail.com>:
> >>>> I am getting the following message when I unload a scene. I am simply
> >>>> deleting the entities I don't have to display anymore.
> >>>> 
> >>>> QMetaProperty::read: Unable to handle unregistered datatype
> >>>> 'Qt3DRender::QBuffer*' for property 'Qt3DRender::QAttribute::buffer'
> >>>> 
> >>>> What is the proper way to unload meshes in c++? Need I also delete all
> >>>> attached components (QGeometryRenderer, QBuffer, ...)?
> >>>> 
> >>>> --
> >>>> Xavier
> >>> 
> >>> --
> >>> Xavier
> >>> 
> >>> _______________________________________________
> >>> Interest mailing list
> >>> Interest at qt-project.org
> >>> http://lists.qt-project.org/mailman/listinfo/interest
> > 
> > --
> > Xavier

--
Dr Sean Harmer | sean.harmer at kdab.com | Managing Director UK
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