This video is now six years old, and Corona Scatter has been replaced with the much more powerful Chaos Scatter which brings with it easier and more flexible workflows that make the techniques shown here redundant. See for the updated tutorial for 3ds Max and for the tutorial for Cinema 4D.
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In this tutorial, we’ll look at using the Corona Distance Map to keep paths, roads and the area around specific objects clear of plants and trees, plus how to use the Falloff map to control scattering based on slope.