I have drawn a line with:

val line = graphics {
        stroke(
            ColorPaint(Colors.LIGHTGRAY),
            Context2d.StrokeInfo(thickness = 1.0)
        ) {
            moveTo(e1.v1.pos.x + VERTEX_RADIUS, e1.v1.pos.y + VERTEX_RADIUS)
            lineTo(e1.v2.pos.x + VERTEX_RADIUS, e1.v2.pos.y + VERTEX_RADIUS)
        }

Is it possible to change the color of this line afterwards? If not, what should I use to draw the line instead?

There is a single line?

I want to change the color when certain state changes. What do you mean with redraw?

Ah, thnx. I will play with this

👍