Add another layer of fabrics, adjust the opacity of both layers, add more coverage to high lights and surfaces looked at from a sharp Angle, and define the outline with brighter lines.

添加其他面料图层，调整两个图层的透明度，在从一个小角度看到的表面增加更多的覆盖高光，并确定明亮的细线条轮廓。

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And in the image of Moscow-Sheremetyevo airport, the flat concrete surfaces of the runways appear as black lines because the radar beam has been very efficiently reflected away from the satellite.

BBC: German TanDEM-X satellite returns first images