Hi Riccardo, As far as I could tell Qt is designed to only allow you to drive it's event and rendering loop from the applications main thread. I tried lots of different combinations of threading to get round this but didn't succeed. Perhaps separate process might be able to do it.
Robert. On Tue, Dec 1, 2009 at 4:46 PM, Riccardo Corsi <[email protected]> wrote: > Hi Robert and All, > > I'm revamping this thread 'cause my question is related to it. > Simon knows much more than I do about windows event handling, but I have > tried to run the osgQtBrowser example under WinXP, and it works fine (with > active navigation) both in threaded and single thread mode. > > But on my side, I'd like to go the opposite way, which is having the control > of the main thread and spawn a new one for the Qt browser. > So far I've successfully isolated the Qt code in a component, not to > "pollute" the main application code. This way it's easier to plug this > component into any existing application. > But with this single-threaded approach, the application hiccups when the > page is loading (i.e. when the qtBrowser is retrieving network data), same > as when osgQtBrowser run in single thread. > > Do you think it's possible to spawn this qt data loading in a separate > thread, and then still connect to the "change" signal to update the image on > the osg side? > This new thread should also forward events to the WebView though, otherwise > navigation is no more possible... > I've checked the Qt documentation, but could not find a clean way to handle > this case. > > Thank you, > Ricky > > > On Tue, Oct 20, 2009 at 1:11 PM, Simon Hammett <[email protected]> > wrote: >> >> 2009/10/20 J.P. Delport <[email protected]>: >> > Hi Simon, >> > >> > Simon Hammett wrote: >> >>> >> >>> I will try osgqtbrowser on Windows and >> >>> see what happens. >> >>> >> >>> Anyone else have reports on osgqtbrowser on Windows? >> >>> >> >>> thanks >> >>> jp >> >>> >> >> Windozes is same as Mac, only the owner thread can retrieve events for >> >> windows. >> > >> > can you expand on what you mean by "owner". If a thread other than main >> > creates the viewer and that same thread calls frame(), will that work on >> > Windows? >> > >> > jp >> >> Sort of. >> >> When a thread first creates a window, windows also creates the message >> queue for the thread. >> Windows messages are per thread, so only the thread which owns the >> window will see the >> messages for the window in it's event loop, so you can't have another >> thread process mouse events, etc. >> >> The pure gl stuff does work though, so you can draw from another thread. >> >> With windows you should really make sure only one thread actually >> creates windows as if you >> have multiple windows in different threads the only safe >> synchronisation primitive is MsgWaitForMultipleObjects which is a huge >> pain in the butt. >> >> I've had a go at doing a properly separately threaded viewer window >> before and even being extra careful I couldn't stop it dead locking. >> >> > >> > -- >> > This message is subject to the CSIR's copyright terms and conditions, >> > e-mail >> > legal notice, and implemented Open Document Format (ODF) standard. The >> > full >> > disclaimer details can be found at >> > http://www.csir.co.za/disclaimer.html. >> > >> > This message has been scanned for viruses and dangerous content by >> > MailScanner, and is believed to be clean. MailScanner thanks Transtec >> > Computers for their support. >> > >> > _______________________________________________ >> > osg-users mailing list >> > [email protected] >> > >> > http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org >> > >> >> >> >> -- >> http://www.ssTk.co.uk >> _______________________________________________ >> osg-users mailing list >> [email protected] >> http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org > > > > -- > Riccardo Corsi > (t) +39 011 56 97 227 > (f) +39 011 56 97 219 > Virtual Reality & Multi Media Park SpA > C.so Lombardia, 194 10149 Torino (It) > C.F./P.I. 07844090014 > C.S. deliberato € 2.220.240,80 - sottoscritto € 1.965.941,20 - versato € > 819.253,90 > Reg. Impr. TO-07844090014 > R.E.A. 924212 > > _______________________________________________ > osg-users mailing list > [email protected] > http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org > > _______________________________________________ osg-users mailing list [email protected] http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
