Dynamically updating Polyline points in tornadofx

This question is a bit simplistic, but i couldn't figure it out for myself... What I'm trying to do is using a JavaFX Timeline to update my Polyline points. What I've got until now is as follows:

class MainView : View("Hello TornadoFX") {
    var myLine: Polyline by singleAssign()
    val myTimeline = timeline {
        cycleCount = INDEFINITE
    }

    override val root = hbox {
        myLine = polyline(0.0, 0.0, 100.0, 100.0)
        myTimeline.apply {
            keyFrames += KeyFrame((1/10.0).seconds, {
                myLine.points.forEachIndexed { i, d ->
                    myLine.points[i] = d + 1
                }
                println(myLine.points)
            })
            play()
        }
    }
}

Although the point list does update the values, as shown when printing them, the change is not reflected in the ui.

Thank you very much for your help!

Figured out that the issue was simply using an hbox as the parent layout, instead of a pane, which handles the chidren positioning with absolute coordinates.