Polygon height geographical offset slider

[ErikKjellman]

I would like a widget that could adjust the geografical (Z) offset of a polygon by sliding between given values. In my sample I have a slider to the right which is used to adjust the sea level (polygon) in a local 3d-scne with a high resolution (1m) elevation model as gound, draped by orthophoto basemap. By sliding up or down the user can see the effect of land rise.