Post
A modern shadow technique that stores massive virtual shadow textures and only resolves the parts the camera actually sees.
Traditional shadow maps require a fixed resolution for the whole light. Virtual Shadow Maps (VSMs), popularized by Unreal Engine 5, allocate a huge logical shadow texture but only allocate physical memory for the visible tiles, similar to virtual texturing. The result is per-pixel shadow detail everywhere the camera looks, with dramatically less memory than a single high-res shadow map would cost.
Example
Unreal Engine 5's VSM is the showcase implementation. Fortnite Chapter 4 became one of the first large-scale tests of the technique. Newer console titles like Lords of the Fallen use it for per-object shadow detail that was impossible on last-gen.
Why it matters
Virtual Shadow Maps represent the latest generation of shadow tech, replacing the cascaded shadow map approach that dominated for 15+ years. They are a key reason UE5 titles look so crisp in lighting and a foundation for the next decade of shadow rendering.
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