import QtQuick

Window {
    width: 640
    height: 480
    visible: true
    title: qsTr("Pendulum Swing")

    readonly property int pendulumAngle: 30
    readonly property int animDuration: 700

    Rectangle{
        id: pendulumId
        width: 20
        height: 200
        color: "black"
        x: (parent.width - width)/2
        y: 50
        transformOrigin: Item.Top

        Rectangle{
            id: bobId
            width: 50
            height: 50
            color: "red"
            radius: width/2
            x: (pendulumId.width - width)/2
            y: pendulumId.height
            transformOrigin: Item.Bottom
            rotation: pendulumId.rotation
        }

        SequentialAnimation{
            loops: Animation.Infinite
            running: true
            NumberAnimation{
                id: rightToLeftAnimationId
                target: pendulumId
                property: "rotation"
                from: -pendulumAngle
                to: pendulumAngle
                duration: animDuration
                easing.type: Easing.InOutQuad
            }

            NumberAnimation{
                id: leftToRightAnimationId
                target: pendulumId
                property: "rotation"
                from: pendulumAngle
                to: -pendulumAngle
                duration: animDuration
                easing.type: Easing.InOutQuad
            }
        }
    }
}