On Fri, Mar 14, 2014 at 04:12:02PM +0100, Jocelyn Turcotte wrote: > On Fri, Mar 14, 2014 at 03:49:21PM +0100, Christoph Kurz wrote: > > Now, if there is more than enough graphics power, ItemA and ItemB are > > rendered > > with 60fps; If there is just enough power, ItemA is rendered with 40fps, > > ItemB > > with 30fps. If there is not enough power for this, then ItemA could be > > rendered > > with 20fps, ItemB with 15fps. > > If the scene is rendered without some items, those items will disapear > from the screen as well, this is probably not what you waht. You could > instead to store the result of the rendering of a complex branch of the > scene into a FramebufferObject and simply blit it on frames where it isn't > modified. > > This however comes at the price of using memory to store those pixels > between frames. > > > Now the questions: > > - Is that (or something similar) possible with the Qt scenegraph? > > "layer.enabled: true" should be enough to trigger intermediate rendering, > but I haven't tried it myself so there might be some details I'm missing. > > http://qt-project.org/doc/qt-5/qml-qtquick-item.html#layer.enabled-prop > > > - How much effort would it be to implement it? > > Hopefully the above trick helps, the solution you propose sounds quite, > humm, complex. > > > - Do you have useful links to additional articles / blogs that shed more > > light > > on the scenegraph internals? > > For an overview: > http://qt-project.org/doc/qt-5/qtquick-visualcanvas-scenegraph-renderer.html
Wrong link, this one is the actual overview: http://qt-project.org/doc/qt-5/qtquick-visualcanvas-scenegraph.html > For more details the code is quite readable in most parts. Have a look > under qtdeclarative/src/quick/scenegraph/. > > Cheers, > Jocelyn > _______________________________________________ > Development mailing list > Development@qt-project.org > http://lists.qt-project.org/mailman/listinfo/development _______________________________________________ Development mailing list Development@qt-project.org http://lists.qt-project.org/mailman/listinfo/development
