Here are some of my early R&D videos for using normal maps and layered normal maps on terrain.  Keep in mind that this is from back when widespread use of normal maps and “next gen” techniques were fairly new.

Technique #1 – Normal Map large features of terrain

This video shows using a normal map derived from a high resolution terrain mesh applied to a low resolution mesh.

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Technique #2 – Layered Normal Maps

This video shows a possible shader that leverages a couple of simple noise normal maps sized differently and blended together to achieve a large, medium, and fine detail visual.

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