In The Witcher 4 tech demo presented during the State of Unreal 2025, the majority of foliage was generated at runtime on the GPU using PCG. This feature has been available since Unreal Engine 5.5, though significant optimizations were introduced in version 5.6. Keep in mind that it’s still experimental and requires a basic understanding of HLSL.
Epic Games’ Tools Programmer Adrien Logut has released an introductory video on GPU-based generation, where he explains how to enable GPU execution on supported nodes, create custom HLSL nodes for point generation, sample landscapes directly on the GPU, and understand both the limitations and advantages of GPU-driven workflows.
Grab the project files and check out the PCG GPU documentation here. This video is part of Adrien’s PCG tutorial series, which you can find in the dedicated playlist. Also, subscribe to his YouTube channel to stay updated and learn directly from an Unreal Engine engineer:
