Consider a model of an airport, in which the data provider wishes to place a strobing light string along a runway. The light emitted is negligible at an ordinary viewing range, in terms of cast shadows and so on, so it is most efficient to represent it as follows.
Since the <Line>'s count is greater than zero, it does not appear to be solid; each of its <Vertex> components is shown independently. The light_diameter in pixels is not applicable, and the light is visible at any distance since no extingishing range is specified. The runway lights will always be on, unless a <Light Rendering Properties Control Link> is added. The lights strobe every two seconds.