Hi, On 15/12/2010, at 9:02 PM, ext Cornelius Hald wrote:
> On Tue, 2010-12-14 at 15:59 +0100, Thomas Perl wrote: >> How would a cross-platform "make it fast" code snippet look like that >> gives the best result on both Maemo and Symbian^3 as well as on >> Desktop platforms and future MeeGo devices? > > Even if we don't have fast cross-platform defaults, it would be > interesting what the optimal settings are for the individual platforms. > For example on Symbian^1 (XpressMusic 5880) I get horrible performance > with the defaults. > > For Maemo5 I'm getting good (not great) performance with: > > #if defined(Q_WS_MAEMO_5) > setAttribute(Qt::WA_OpaquePaintEvent); > setAttribute(Qt::WA_NoSystemBackground); > setViewport(new QGLWidget()); > setViewportUpdateMode(QGraphicsView::FullViewportUpdate); > #endif If you aren't doing so already, I'd suggest also: * running using the raster graphics system (i.e. raster + GL viewport). This has an impact because so many of the items cache their drawing to pixmaps. * turning off sample buffers (below is what we do in qmlviewer), as long as the graphical results are acceptable to you QGLFormat format = QGLFormat::defaultFormat(); format.setSampleBuffers(false); QGLWidget *glWidget = new QGLWidget(format); //### potentially faster, but causes junk to appear if top-level is Item, not Rectangle //glWidget->setAutoFillBackground(false); view->setViewport(glWidget); * As mentioned in an earlier reply, running fullscreen rather than maximized if possible (compositing is quite expensive, and avoiding it gives a very nice performance bump) Regards, Michael _______________________________________________ Qt-qml mailing list [email protected] http://lists.qt.nokia.com/mailman/listinfo/qt-qml
