SDFs (Signed Distance Fields) are an amazing optimization to marching a ray through a scene. Unreal Engine 4 uses them for ambient occlusion https://docs.unrea

SDFs (Signed Distance Fields) are an amazing optimization to marching a ray through a scene. Unreal Engine 4 uses them for ambient occlusion https://docs.unrealengine.com/latest/INT/Engine/Rendering/LightingAndShadows/DistanceFieldAmbientOcclusion/index.html#howdoesitwork https://docs.unrealengine.com/latest/INT/Engine/Rendering/Li... and soft shadows https://docs.unrealengine.com/latest/INT/Engine/Rendering/LightingAndShadows/RayTracedDistanceFieldShadowing/index.html https://docs.unrealengine.com/latest/INT/Engine/Rendering/Li... The author mentions Inigo Quilez, an incredible demoscene artist, who has an amazing writeup of how he uses SDFs for creating the geometry in demos: http://iquilezles.org/www/material/nvscene2008/rwwtt.pdf http://iquilezles.org/www/material/nvscene2008/rwwtt.pdf I remember when it "clicked" for me... instead of defining geometry and generating SDFs for use in shading, which is expensive, he was generating SDFs directly to be used as the definition for geometry! It's brilliant.