Hello, Y. You should be able to do it by defining an appropriate FillRule on the map layer, similar to what's outlined in this tutorial . If the range of values you expect is between 0 and 1000, for instance, you might define this set of stops: < my : MapLayer.FillRule > < my : MapLayerFillRule Binding = "{Binding MyValue}" > < my : MapLayerFillRule.Colors > < LinearGradientBrush > < GradientStop Offset = "0" Color = "Black" /> <...