[solved] Qt Quick 2 performance issues

[Schneidi]

Hello, I started a new project in which I need to render Qml content on an WQHD display (2560 x 1440).
And I'm still trying to get a pretty basic qml test to run fluently. But on the full resolution the rendering performance drops way below 10 fps.
The target system runs a AMD G-T56N dual core processor 1,6 GHz 3,5 GiB ram and a dedicated AMD Radeon HD 6310 graphics card.

My qml Test is nothing more than this:
@import QtQuick 2.0

Item {
id: grid_view
width: 800
height: 600

Rectangle {
    id: grid_view_bg
    anchors.fill: parent

    ListModel {
        id: employee_model
        ListElement { name: "User 1"; }
        ListElement { name: "User 2"; }
        ListElement { name: "User 3"; }
        ListElement { name: "User 4"; }
        ListElement { name: "User 5"; }
        ListElement { name: "User 6"; }
        ListElement { name: "User 7"; }
        ListElement { name: "User 8"; }
        ListElement { name: "User 9"; }
        ListElement { name: "User 10"; }
    }
    Component {
        id: employeeDelegate
        Item {
            id:employeeContainer
            width: 180;
            height: 200
            Rectangle {
                id:employeeBody
                anchors.fill: parent
                anchors.rightMargin: 5
                color: "red"
                border.color: "black"

                Rectangle {
                    id: employeeHeader
                    z:101
                    color: "#bbdbf3"
                    anchors.horizontalCenter: parent.horizontalCenter
                    width: parent.width
                    height: 40
                    Text {
                        anchors.centerIn: parent
                        text: '<b>Name:</b> ' + name
                    }
                    border.color: "black"

                }
            }
        }
    }
    ListView {
        anchors.fill: parent
        model: employee_model
        orientation: Qt.Horizontal
        delegate: employeeDelegate
    }
}

}@

The main.cpp:
@QGuiApplication app(argc, argv);

QtQuick2ApplicationViewer viewer;
viewer.setMainQmlFile(QStringLiteral("qml/untitled/main.qml"));
viewer.show();

@

So I just used the predefined QtQuick 2 Application example to start with.
Even on my development system running an intel quad core with dedicated ATI Radeon HD 3450 the performance start to decrease at a 1920 x 1080 resolution. The higher the resolution gets the worse is the performance. At the full WQHD resolution it is just unusable.

What might be the problem here ?
I would expect that qt is capable of a way better performance than what i get right now.
Both cards support at least OpenGL 3 or higher.
What can i do to get the qml animation on the list scrolling to run smooth.

I could need some help with this one.
Thank you for any help.

[sierdzio]

Are you using Qt 5.2? What OS are you on? Have you compiled Qt yourself (or maybe we are talking about an ANGLE build)?

I think in Qt 5.2 you can bump the version number to QtQuick 2.1, BTW.

[Schneidi]

Hi,

I'm using Qt 5.1.1 compiled by myself on Ubuntu on both systems.
May there be any performance difference between 5.1.1 and 5.2 ?

[sierdzio]

Yes, the rendering engine has been significantly optimised (see "this":http://blog.qt.digia.com/blog/2013/09/02/new-scene-graph-renderer/ blog entry).

If possible, compile Qt with "-opengl desktop" flag. It will make the most of your GPU.

[Schneidi]

Ok thanks I'm going to compile Qt 5.2 with the opengl desktop flag and see what happens.

[Schneidi]

Hey thanks for the hint sierdzio.
It's amazing. On Qt5.2 the example runs so much better then with 5.1.1.
Awesome piece the new scene graph.

Thumbs up.

[sierdzio]

hey, great! I'm happy that it helped you :)