This gets me thinking: it would be really nice if there were more information on what exactly QML is doing behind the scene. What impacts performance, and what doesn't.
What costs the most, in QML? Bindings? Javascript evaluation? Memory allocation for items? And why? Yes, I'm aware that some of those questions have an answer on http://doc.qt.nokia.com/main-snapshot/qdeclarativeperformance.html but they only give the do's and dont's here, not the why. On Wed, Aug 4, 2010 at 5:17 PM, Jan Ekholm <jan.ekh...@smultron.net> wrote: > On Wednesday 04 August 2010 05:53:13 michael.bras...@nokia.com wrote: >> Hi, >> >> On 03/08/2010, at 4:55 AM, ext Jan Ekholm wrote: >> > I was recommended to make a C++ QDeclarativeItem subclass for my game map >> > tiles to get better performance. This worked well >> >> Given the simplicity of the QML tile (from http://gitorious.org/tactics), >> I'm a bit surprised that using a C++ item made a difference in >> performance. What sort of performance issues were you seeing, and on what >> platform(s)? > > The most noticeable difference is when creating the scene, i.e. when the QML > file is loaded. A base based on the old Image item that I used instead of a > C++ Hex took a lot longer to set up. I tried to get rid of the slow sounding > Repeater too, but that can not be done with QML just yet. But that simple > change made scenes much faster to load and the panning is a bit smoother too. > > I never really had any panning issues, not even on an N900, but setup time was > not exactly fast. As there is a fair deal of QML used the time just seemed to > get longer and longer. On a fast desktop PC it took 3-10 to load the initial > game QML file that also sets up the map. Now it's much faster. > > -- > "Right, you bastards, you're... you're geography" > -- Terry Pratchett, Guards! Guards! > > _______________________________________________ > Qt-qml mailing list > Qt-qml@trolltech.com > http://lists.trolltech.com/mailman/listinfo/qt-qml > _______________________________________________ Qt-qml mailing list Qt-qml@trolltech.com http://lists.trolltech.com/mailman/listinfo/qt-qml
