Virtual joystick with QML

    import QtQuick 2.0

    Item {
        signal pressed(real x, real y)
        signal moved(real x, real y)
        signal released
        id: joystick
        width: 160
        height: 160
        onPressed: console.log("Pressed:", x, y)
        onMoved: console.log("Moved:", x, y)
        onReleased: console.log("Released")
        Image {
            id: backgroundImage
            anchors.fill: parent
            source: "background.png"
        }
        Item {
            id: finger
            width: 26
            height: 26
            x: 80-13
            y: 80-13
            Image {
                id: fingerImage
                anchors.fill: parent
                source: "finger.png"
            }
        }
        MouseArea {
            id: joystickArea
            anchors.fill: parent
            property int signX: 1
            property int signY: 1
            PropertyAnimation {
                id: returnToOrigin
                target: finger
                properties: "x,y"
                to: 80-13
                duration: 100
            }
            onPressed: joystick.pressed(joystickArea.mouseX, joystickArea.mouseY)
            onPositionChanged: {
                if (Math.pow(joystickArea.mouseX-80, 2) + Math.pow(joystickArea.mouseY-80, 2) < Math.pow(80-13, 2)) {
                    finger.x = joystickArea.mouseX-13
                    finger.y = joystickArea.mouseY-13
                    80 - joystickArea.mouseX > 0 ? signX = 1 : signX = -1
                    80 - joystickArea.mouseY > 0 ? signY = 1 : signY = -1
                    joystick.moved(-(80+13*signX-joystickArea.mouseX)/80, (80+13*signY-joystickArea.mouseY)/80)
                } else {
                    // else what?
                }
            }
            onReleased: {
                returnToOrigin.start()
                joystick.released()
            }
        }
    }