Nanite Foliage and Translucency
Dylan Browne demonstrates a 321 billion-polygon forest on UE5 (77,376 instances of 20 million poly trees). Nanite Foliage leverages a voxel-based method to achieve dense forests. The Witcher 4 uses it and it about to be debut in the upcoming release of Unreal Engine 5.
He also did a fascinating ray-traced translucency experiment
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