Wolfram Technology Guide: Automated Computational Aesthetics  previous | next 
Use Transparency for 3D Filling
A single line of input automatically generates an attractive multisheeted 3D graphic.
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Click for copyable input
Plot3D[{Sin[x y], Cos[x + y]}, {x, 0, 3}, {y, 0, 3}, 

 Filling -> Bottom]
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