Add animation when use camera.roll(real angel)

[Son Nguyen Ngoc]

Hi all,
I use roll(real angel) method to change roll angel of camera in Qt3d but, i have no idea to add animation to this action. I don't know what property of camera is changed by that method. For example:

Camera {
id: camera
projectionType: CameraLens.PerspectiveProjection
fieldOfView: 45
aspectRatio: 4/3
nearPlane : 0.1
farPlane : 1000.0
position: Qt.vector3d(0, -100, 30)
upVector: Qt.vector3d( 0, 1, 0 )
viewCenter: Qt.vector3d(0, 0, 0)
}

function changeRollAngel(action)
{
    if(action == 1)
    {
        camera.roll(5)
    }
    else if(action == -1)
    {
        camera.roll(-5)
    }
}