Render QML scene problem
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Hello All!
My previous question was not answered, and I'll try to explain more clearly, and sory for my bad english.I develop application for embeded system (AM3517 processor based, EGLFS platform).
I have very big QML scene (several dozen of Rectangle{} and Text{} items), and I need display little xy-plot in QML scene. This xy-plot should be updated very often (50 Hz). The trouble is that a QQuickWindow::update() function call is hard CPU-intensive. As I understand it, time of this function depends on how many nodes in scene graph.
I tried to use rendering to FBO (http://qt-project.org/doc/qt-5.1/qtquick/scenegraph-textureinsgnode.html), but this example use full update of scene (call m_window->update(); in TextureNode class). For simple QML scene is not significantly, but for my case is important.
I tired to use Canvas{} element, but i need call Canvas::requestPaint() function for every frame, and this leads to call update() function too.Is there a way to update only a small area of the screen, without an analysis of the entire scene graph?
Is there a way to make the scene graph renderer does not run all over the scene graph by drawing a single pixel?
maybe there is a workaround to update the small area in QML scene?My Qt version is 5.0.
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This is best asked on interest "mailing list":http://lists.qt-project.org/mailman/listinfo/interest. Still no guarantee you'll get an answer, but it's a bit more probable. As an absolute last resort, use development ML.